From: Harlan Stenn Date: Wed, 9 Apr 2014 10:24:43 +0000 (+0000) Subject: NTP_4_2_7P440 X-Git-Tag: NTP_4_2_7P440^0 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=af18600bb1720f20a1a9ce9f215ca2f00e6f8b9d;p=thirdparty%2Fntp.git NTP_4_2_7P440 bk: 53451feb8Nj5zL7pMHfrXCKhaL9E9Q --- diff --git a/ChangeLog b/ChangeLog index e8f247134..8fc2f9d9e 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,4 @@ +(4.2.7p440) 2014/04/09 Released by Harlan Stenn * [Bug 2536] ntpd sandboxing support (libseccomp2) cleanup. * [Bug 2570] cleanup: fix log format for successful leapfile load (4.2.7p439) 2014/04/03 Released by Harlan Stenn diff --git a/ntpd/invoke-ntp.conf.texi b/ntpd/invoke-ntp.conf.texi index 0e70faa04..a844a5a02 100644 --- a/ntpd/invoke-ntp.conf.texi +++ b/ntpd/invoke-ntp.conf.texi @@ -6,7 +6,7 @@ # # EDIT THIS FILE WITH CAUTION (invoke-ntp.conf.texi) # -# It has been AutoGen-ed April 2, 2014 at 10:47:33 AM by AutoGen 5.18.3pre18 +# It has been AutoGen-ed April 9, 2014 at 10:03:37 AM by AutoGen 5.18.3pre18 # From the definitions ntp.conf.def # and the template file agtexi-file.tpl @end ignore diff --git a/ntpd/invoke-ntp.keys.texi b/ntpd/invoke-ntp.keys.texi index 81e335344..f50aec68d 100644 --- a/ntpd/invoke-ntp.keys.texi +++ b/ntpd/invoke-ntp.keys.texi @@ -6,7 +6,7 @@ # # EDIT THIS FILE WITH CAUTION (invoke-ntp.keys.texi) # -# It has been AutoGen-ed April 2, 2014 at 10:47:36 AM by AutoGen 5.18.3pre18 +# It has been AutoGen-ed April 9, 2014 at 10:03:41 AM by AutoGen 5.18.3pre18 # From the definitions ntp.keys.def # and the template file agtexi-file.tpl @end ignore diff --git a/ntpd/invoke-ntpd.texi b/ntpd/invoke-ntpd.texi index e73a047ea..f76acbabb 100644 --- a/ntpd/invoke-ntpd.texi +++ b/ntpd/invoke-ntpd.texi @@ -6,7 +6,7 @@ # # EDIT THIS FILE WITH CAUTION (invoke-ntpd.texi) # -# It has been AutoGen-ed April 2, 2014 at 10:47:38 AM by AutoGen 5.18.3pre18 +# It has been AutoGen-ed April 9, 2014 at 10:03:43 AM by AutoGen 5.18.3pre18 # From the definitions ntpd-opts.def # and the template file agtexi-cmd.tpl @end ignore @@ -141,7 +141,7 @@ with a status code of 0. @exampleindent 0 @example -ntpd - NTP daemon program - Ver. 4.2.7p439 +ntpd - NTP daemon program - Ver. 4.2.7p440 Usage: ntpd [ - [] | --[@{=| @}] ]... \ [ ... ] Flg Arg Option-Name Description diff --git a/ntpd/ntp.conf.5man b/ntpd/ntp.conf.5man index b2f285973..8b1378917 100644 --- a/ntpd/ntp.conf.5man +++ b/ntpd/ntp.conf.5man @@ -1,3020 +1 @@ -.de1 NOP -. it 1 an-trap -. if \\n[.$] \,\\$*\/ -.. -.ie t \ -.ds B-Font [CB] -.ds I-Font [CI] -.ds R-Font [CR] -.el \ -.ds B-Font B -.ds I-Font I -.ds R-Font R -.TH ntp.conf 5man "02 Apr 2014" "4.2.7p439" "File Formats" -.\" -.\" EDIT THIS FILE WITH CAUTION (/tmp/.ag-QxaqsZ/ag-CyaqrZ) -.\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:09 AM by AutoGen 5.18.3pre18 -.\" From the definitions ntp.conf.def -.\" and the template file agman-cmd.tpl -.SH NAME -\f\*[B-Font]ntp.conf\fP -\- Network Time Protocol (NTP) daemon configuration file format -.SH SYNOPSIS -\f\*[B-Font]ntp.conf\fP -[\f\*[B-Font]\-\-option-name\f[]] -[\f\*[B-Font]\-\-option-name\f[] \f\*[I-Font]value\f[]] -.sp \n(Ppu -.ne 2 -All arguments must be options. -.sp \n(Ppu -.ne 2 - -.SH DESCRIPTION -The -\f\*[B-Font]ntp.conf\fP -configuration file is read at initial startup by the -\fCntpd\fR(1ntpdmdoc)\f[] -daemon in order to specify the synchronization sources, -modes and other related information. -Usually, it is installed in the -\fI/etc\f[] -directory, -but could be installed elsewhere -(see the daemon's -\f\*[B-Font]\-c\f[] -command line option). -.sp \n(Ppu -.ne 2 - -The file format is similar to other -UNIX -configuration files. -Comments begin with a -\[oq]#\[cq] -character and extend to the end of the line; -blank lines are ignored. -Configuration commands consist of an initial keyword -followed by a list of arguments, -some of which may be optional, separated by whitespace. -Commands may not be continued over multiple lines. -Arguments may be host names, -host addresses written in numeric, dotted-quad form, -integers, floating point numbers (when specifying times in seconds) -and text strings. -.sp \n(Ppu -.ne 2 - -The rest of this page describes the configuration and control options. -The -"Notes on Configuring NTP and Setting up an NTP Subnet" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]) -contains an extended discussion of these options. -In addition to the discussion of general -\fIConfiguration\f[] \fIOptions\f[], -there are sections describing the following supported functionality -and the options used to control it: -.IP \fB\(bu\fP 2 -\fIAuthentication\f[] \fISupport\f[] -.IP \fB\(bu\fP 2 -\fIMonitoring\f[] \fISupport\f[] -.IP \fB\(bu\fP 2 -\fIAccess\f[] \fIControl\f[] \fISupport\f[] -.IP \fB\(bu\fP 2 -\fIAutomatic\f[] \fINTP\f[] \fIConfiguration\f[] \fIOptions\f[] -.IP \fB\(bu\fP 2 -\fIReference\f[] \fIClock\f[] \fISupport\f[] -.IP \fB\(bu\fP 2 -\fIMiscellaneous\f[] \fIOptions\f[] -.PP -.sp \n(Ppu -.ne 2 - -Following these is a section describing -\fIMiscellaneous\f[] \fIOptions\f[]. -While there is a rich set of options available, -the only required option is one or more -\f\*[B-Font]pool\f[], -\f\*[B-Font]server\f[], -\f\*[B-Font]peer\f[], -\f\*[B-Font]broadcast\f[] -or -\f\*[B-Font]manycastclient\f[] -commands. -.SH Configuration Support -Following is a description of the configuration commands in -NTPv4. -These commands have the same basic functions as in NTPv3 and -in some cases new functions and new arguments. -There are two -classes of commands, configuration commands that configure a -persistent association with a remote server or peer or reference -clock, and auxiliary commands that specify environmental variables -that control various related operations. -.SS Configuration Commands -The various modes are determined by the command keyword and the -type of the required IP address. -Addresses are classed by type as -(s) a remote server or peer (IPv4 class A, B and C), (b) the -broadcast address of a local interface, (m) a multicast address (IPv4 -class D), or (r) a reference clock address (127.127.x.x). -Note that -only those options applicable to each command are listed below. -Use -of options not listed may not be caught as an error, but may result -in some weird and even destructive behavior. -.sp \n(Ppu -.ne 2 - -If the Basic Socket Interface Extensions for IPv6 (RFC-2553) -is detected, support for the IPv6 address family is generated -in addition to the default support of the IPv4 address family. -In a few cases, including the reslist billboard generated -by ntpdc, IPv6 addresses are automatically generated. -IPv6 addresses can be identified by the presence of colons -\*[Lq]\&:\*[Rq] -in the address field. -IPv6 addresses can be used almost everywhere where -IPv4 addresses can be used, -with the exception of reference clock addresses, -which are always IPv4. -.sp \n(Ppu -.ne 2 - -Note that in contexts where a host name is expected, a -\f\*[B-Font]\-4\f[] -qualifier preceding -the host name forces DNS resolution to the IPv4 namespace, -while a -\f\*[B-Font]\-6\f[] -qualifier forces DNS resolution to the IPv6 namespace. -See IPv6 references for the -equivalent classes for that address family. -.TP 7 -.NOP \f\*[B-Font]pool\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]burst\f[]] [\f\*[B-Font]iburst\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] -.TP 7 -.NOP \f\*[B-Font]server\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]\&|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]burst\f[]] [\f\*[B-Font]iburst\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] -.TP 7 -.NOP \f\*[B-Font]peer\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]\&|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] -.TP 7 -.NOP \f\*[B-Font]broadcast\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]\&|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]ttl\f[] \f\*[I-Font]ttl\f[]] -.TP 7 -.NOP \f\*[B-Font]manycastclient\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]\&|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] [\f\*[B-Font]ttl\f[] \f\*[I-Font]ttl\f[]] -.PP -.sp \n(Ppu -.ne 2 - -These five commands specify the time server name or address to -be used and the mode in which to operate. -The -\f\*[I-Font]address\f[] -can be -either a DNS name or an IP address in dotted-quad notation. -Additional information on association behavior can be found in the -"Association Management" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.TP 7 -.NOP \f\*[B-Font]pool\f[] -For type s addresses, this command mobilizes a persistent -client mode association with a number of remote servers. -In this mode the local clock can synchronized to the -remote server, but the remote server can never be synchronized to -the local clock. -.TP 7 -.NOP \f\*[B-Font]server\f[] -For type s and r addresses, this command mobilizes a persistent -client mode association with the specified remote server or local -radio clock. -In this mode the local clock can synchronized to the -remote server, but the remote server can never be synchronized to -the local clock. -This command should -\fInot\f[] -be used for type -b or m addresses. -.TP 7 -.NOP \f\*[B-Font]peer\f[] -For type s addresses (only), this command mobilizes a -persistent symmetric-active mode association with the specified -remote peer. -In this mode the local clock can be synchronized to -the remote peer or the remote peer can be synchronized to the local -clock. -This is useful in a network of servers where, depending on -various failure scenarios, either the local or remote peer may be -the better source of time. -This command should NOT be used for type -b, m or r addresses. -.TP 7 -.NOP \f\*[B-Font]broadcast\f[] -For type b and m addresses (only), this -command mobilizes a persistent broadcast mode association. -Multiple -commands can be used to specify multiple local broadcast interfaces -(subnets) and/or multiple multicast groups. -Note that local -broadcast messages go only to the interface associated with the -subnet specified, but multicast messages go to all interfaces. -In broadcast mode the local server sends periodic broadcast -messages to a client population at the -\f\*[I-Font]address\f[] -specified, which is usually the broadcast address on (one of) the -local network(s) or a multicast address assigned to NTP. -The IANA -has assigned the multicast group address IPv4 224.0.1.1 and -IPv6 ff05::101 (site local) exclusively to -NTP, but other nonconflicting addresses can be used to contain the -messages within administrative boundaries. -Ordinarily, this -specification applies only to the local server operating as a -sender; for operation as a broadcast client, see the -\f\*[B-Font]broadcastclient\f[] -or -\f\*[B-Font]multicastclient\f[] -commands -below. -.TP 7 -.NOP \f\*[B-Font]manycastclient\f[] -For type m addresses (only), this command mobilizes a -manycast client mode association for the multicast address -specified. -In this case a specific address must be supplied which -matches the address used on the -\f\*[B-Font]manycastserver\f[] -command for -the designated manycast servers. -The NTP multicast address -224.0.1.1 assigned by the IANA should NOT be used, unless specific -means are taken to avoid spraying large areas of the Internet with -these messages and causing a possibly massive implosion of replies -at the sender. -The -\f\*[B-Font]manycastserver\f[] -command specifies that the local server -is to operate in client mode with the remote servers that are -discovered as the result of broadcast/multicast messages. -The -client broadcasts a request message to the group address associated -with the specified -\f\*[I-Font]address\f[] -and specifically enabled -servers respond to these messages. -The client selects the servers -providing the best time and continues as with the -\f\*[B-Font]server\f[] -command. -The remaining servers are discarded as if never -heard. -.PP -.sp \n(Ppu -.ne 2 - -Options: -.TP 7 -.NOP \f\*[B-Font]autokey\f[] -All packets sent to and received from the server or peer are to -include authentication fields encrypted using the autokey scheme -described in -\fIAuthentication\f[] \fIOptions\f[]. -.TP 7 -.NOP \f\*[B-Font]burst\f[] -when the server is reachable, send a burst of eight packets -instead of the usual one. -The packet spacing is normally 2 s; -however, the spacing between the first and second packets -can be changed with the calldelay command to allow -additional time for a modem or ISDN call to complete. -This is designed to improve timekeeping quality -with the -\f\*[B-Font]server\f[] -command and s addresses. -.TP 7 -.NOP \f\*[B-Font]iburst\f[] -When the server is unreachable, send a burst of eight packets -instead of the usual one. -The packet spacing is normally 2 s; -however, the spacing between the first two packets can be -changed with the calldelay command to allow -additional time for a modem or ISDN call to complete. -This is designed to speed the initial synchronization -acquisition with the -\f\*[B-Font]server\f[] -command and s addresses and when -\fCntpd\fR(1ntpdmdoc)\f[] -is started with the -\f\*[B-Font]\-q\f[] -option. -.TP 7 -.NOP \f\*[B-Font]key\f[] \f\*[I-Font]key\f[] -All packets sent to and received from the server or peer are to -include authentication fields encrypted using the specified -\f\*[I-Font]key\f[] -identifier with values from 1 to 65534, inclusive. -The -default is to include no encryption field. -.TP 7 -.NOP \f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[] -.TP 7 -.NOP \f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[] -These options specify the minimum and maximum poll intervals -for NTP messages, as a power of 2 in seconds -The maximum poll -interval defaults to 10 (1,024 s), but can be increased by the -\f\*[B-Font]maxpoll\f[] -option to an upper limit of 17 (36.4 h). -The -minimum poll interval defaults to 6 (64 s), but can be decreased by -the -\f\*[B-Font]minpoll\f[] -option to a lower limit of 4 (16 s). -.TP 7 -.NOP \f\*[B-Font]noselect\f[] -Marks the server as unused, except for display purposes. -The server is discarded by the selection algroithm. -.TP 7 -.NOP \f\*[B-Font]prefer\f[] -Marks the server as preferred. -All other things being equal, -this host will be chosen for synchronization among a set of -correctly operating hosts. -See the -"Mitigation Rules and the prefer Keyword" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]) -for further information. -.TP 7 -.NOP \f\*[B-Font]ttl\f[] \f\*[I-Font]ttl\f[] -This option is used only with broadcast server and manycast -client modes. -It specifies the time-to-live -\f\*[I-Font]ttl\f[] -to -use on broadcast server and multicast server and the maximum -\f\*[I-Font]ttl\f[] -for the expanding ring search with manycast -client packets. -Selection of the proper value, which defaults to -127, is something of a black art and should be coordinated with the -network administrator. -.TP 7 -.NOP \f\*[B-Font]version\f[] \f\*[I-Font]version\f[] -Specifies the version number to be used for outgoing NTP -packets. -Versions 1-4 are the choices, with version 4 the -default. -.PP -.SS Auxiliary Commands -.TP 7 -.NOP \f\*[B-Font]broadcastclient\f[] -This command enables reception of broadcast server messages to -any local interface (type b) address. -Upon receiving a message for -the first time, the broadcast client measures the nominal server -propagation delay using a brief client/server exchange with the -server, then enters the broadcast client mode, in which it -synchronizes to succeeding broadcast messages. -Note that, in order -to avoid accidental or malicious disruption in this mode, both the -server and client should operate using symmetric-key or public-key -authentication as described in -\fIAuthentication\f[] \fIOptions\f[]. -.TP 7 -.NOP \f\*[B-Font]manycastserver\f[] \f\*[I-Font]address\f[] \f\*[I-Font]...\f[] -This command enables reception of manycast client messages to -the multicast group address(es) (type m) specified. -At least one -address is required, but the NTP multicast address 224.0.1.1 -assigned by the IANA should NOT be used, unless specific means are -taken to limit the span of the reply and avoid a possibly massive -implosion at the original sender. -Note that, in order to avoid -accidental or malicious disruption in this mode, both the server -and client should operate using symmetric-key or public-key -authentication as described in -\fIAuthentication\f[] \fIOptions\f[]. -.TP 7 -.NOP \f\*[B-Font]multicastclient\f[] \f\*[I-Font]address\f[] \f\*[I-Font]...\f[] -This command enables reception of multicast server messages to -the multicast group address(es) (type m) specified. -Upon receiving -a message for the first time, the multicast client measures the -nominal server propagation delay using a brief client/server -exchange with the server, then enters the broadcast client mode, in -which it synchronizes to succeeding multicast messages. -Note that, -in order to avoid accidental or malicious disruption in this mode, -both the server and client should operate using symmetric-key or -public-key authentication as described in -\fIAuthentication\f[] \fIOptions\f[]. -.PP -.SH Authentication Support -Authentication support allows the NTP client to verify that the -server is in fact known and trusted and not an intruder intending -accidentally or on purpose to masquerade as that server. -The NTPv3 -specification RFC-1305 defines a scheme which provides -cryptographic authentication of received NTP packets. -Originally, -this was done using the Data Encryption Standard (DES) algorithm -operating in Cipher Block Chaining (CBC) mode, commonly called -DES-CBC. -Subsequently, this was replaced by the RSA Message Digest -5 (MD5) algorithm using a private key, commonly called keyed-MD5. -Either algorithm computes a message digest, or one-way hash, which -can be used to verify the server has the correct private key and -key identifier. -.sp \n(Ppu -.ne 2 - -NTPv4 retains the NTPv3 scheme, properly described as symmetric key -cryptography and, in addition, provides a new Autokey scheme -based on public key cryptography. -Public key cryptography is generally considered more secure -than symmetric key cryptography, since the security is based -on a private value which is generated by each server and -never revealed. -With Autokey all key distribution and -management functions involve only public values, which -considerably simplifies key distribution and storage. -Public key management is based on X.509 certificates, -which can be provided by commercial services or -produced by utility programs in the OpenSSL software library -or the NTPv4 distribution. -.sp \n(Ppu -.ne 2 - -While the algorithms for symmetric key cryptography are -included in the NTPv4 distribution, public key cryptography -requires the OpenSSL software library to be installed -before building the NTP distribution. -Directions for doing that -are on the Building and Installing the Distribution page. -.sp \n(Ppu -.ne 2 - -Authentication is configured separately for each association -using the -\f\*[B-Font]key\f[] -or -\f\*[B-Font]autokey\f[] -subcommand on the -\f\*[B-Font]peer\f[], -\f\*[B-Font]server\f[], -\f\*[B-Font]broadcast\f[] -and -\f\*[B-Font]manycastclient\f[] -configuration commands as described in -\fIConfiguration\f[] \fIOptions\f[] -page. -The authentication -options described below specify the locations of the key files, -if other than default, which symmetric keys are trusted -and the interval between various operations, if other than default. -.sp \n(Ppu -.ne 2 - -Authentication is always enabled, -although ineffective if not configured as -described below. -If a NTP packet arrives -including a message authentication -code (MAC), it is accepted only if it -passes all cryptographic checks. -The -checks require correct key ID, key value -and message digest. -If the packet has -been modified in any way or replayed -by an intruder, it will fail one or more -of these checks and be discarded. -Furthermore, the Autokey scheme requires a -preliminary protocol exchange to obtain -the server certificate, verify its -credentials and initialize the protocol -.sp \n(Ppu -.ne 2 - -The -\f\*[B-Font]auth\f[] -flag controls whether new associations or -remote configuration commands require cryptographic authentication. -This flag can be set or reset by the -\f\*[B-Font]enable\f[] -and -\f\*[B-Font]disable\f[] -commands and also by remote -configuration commands sent by a -\fCntpdc\fR(1ntpdcmdoc)\f[] -program running in -another machine. -If this flag is enabled, which is the default -case, new broadcast client and symmetric passive associations and -remote configuration commands must be cryptographically -authenticated using either symmetric key or public key cryptography. -If this -flag is disabled, these operations are effective -even if not cryptographic -authenticated. -It should be understood -that operating with the -\f\*[B-Font]auth\f[] -flag disabled invites a significant vulnerability -where a rogue hacker can -masquerade as a falseticker and seriously -disrupt system timekeeping. -It is -important to note that this flag has no purpose -other than to allow or disallow -a new association in response to new broadcast -and symmetric active messages -and remote configuration commands and, in particular, -the flag has no effect on -the authentication process itself. -.sp \n(Ppu -.ne 2 - -An attractive alternative where multicast support is available -is manycast mode, in which clients periodically troll -for servers as described in the -\fIAutomatic\f[] \fINTP\f[] \fIConfiguration\f[] \fIOptions\f[] -page. -Either symmetric key or public key -cryptographic authentication can be used in this mode. -The principle advantage -of manycast mode is that potential servers need not be -configured in advance, -since the client finds them during regular operation, -and the configuration -files for all clients can be identical. -.sp \n(Ppu -.ne 2 - -The security model and protocol schemes for -both symmetric key and public key -cryptography are summarized below; -further details are in the briefings, papers -and reports at the NTP project page linked from -\f[C]http://www.ntp.org/\f[]. -.SS Symmetric-Key Cryptography -The original RFC-1305 specification allows any one of possibly -65,534 keys, each distinguished by a 32-bit key identifier, to -authenticate an association. -The servers and clients involved must -agree on the key and key identifier to -authenticate NTP packets. -Keys and -related information are specified in a key -file, usually called -\fIntp.keys\f[], -which must be distributed and stored using -secure means beyond the scope of the NTP protocol itself. -Besides the keys used -for ordinary NTP associations, -additional keys can be used as passwords for the -\fCntpq\fR(1ntpqmdoc)\f[] -and -\fCntpdc\fR(1ntpdcmdoc)\f[] -utility programs. -.sp \n(Ppu -.ne 2 - -When -\fCntpd\fR(1ntpdmdoc)\f[] -is first started, it reads the key file specified in the -\f\*[B-Font]keys\f[] -configuration command and installs the keys -in the key cache. -However, -individual keys must be activated with the -\f\*[B-Font]trusted\f[] -command before use. -This -allows, for instance, the installation of possibly -several batches of keys and -then activating or deactivating each batch -remotely using -\fCntpdc\fR(1ntpdcmdoc)\f[]. -This also provides a revocation capability that can be used -if a key becomes compromised. -The -\f\*[B-Font]requestkey\f[] -command selects the key used as the password for the -\fCntpdc\fR(1ntpdcmdoc)\f[] -utility, while the -\f\*[B-Font]controlkey\f[] -command selects the key used as the password for the -\fCntpq\fR(1ntpqmdoc)\f[] -utility. -.SS Public Key Cryptography -NTPv4 supports the original NTPv3 symmetric key scheme -described in RFC-1305 and in addition the Autokey protocol, -which is based on public key cryptography. -The Autokey Version 2 protocol described on the Autokey Protocol -page verifies packet integrity using MD5 message digests -and verifies the source with digital signatures and any of several -digest/signature schemes. -Optional identity schemes described on the Identity Schemes -page and based on cryptographic challenge/response algorithms -are also available. -Using all of these schemes provides strong security against -replay with or without modification, spoofing, masquerade -and most forms of clogging attacks. -.\" .Pp -.\" The cryptographic means necessary for all Autokey operations -.\" is provided by the OpenSSL software library. -.\" This library is available from http://www.openssl.org/ -.\" and can be installed using the procedures outlined -.\" in the Building and Installing the Distribution page. -.\" Once installed, -.\" the configure and build -.\" process automatically detects the library and links -.\" the library routines required. -.sp \n(Ppu -.ne 2 - -The Autokey protocol has several modes of operation -corresponding to the various NTP modes supported. -Most modes use a special cookie which can be -computed independently by the client and server, -but encrypted in transmission. -All modes use in addition a variant of the S-KEY scheme, -in which a pseudo-random key list is generated and used -in reverse order. -These schemes are described along with an executive summary, -current status, briefing slides and reading list on the -\fIAutonomous\f[] \fIAuthentication\f[] -page. -.sp \n(Ppu -.ne 2 - -The specific cryptographic environment used by Autokey servers -and clients is determined by a set of files -and soft links generated by the -\fCntp-keygen\fR(1ntpkeygenmdoc)\f[] -program. -This includes a required host key file, -required certificate file and optional sign key file, -leapsecond file and identity scheme files. -The -digest/signature scheme is specified in the X.509 certificate -along with the matching sign key. -There are several schemes -available in the OpenSSL software library, each identified -by a specific string such as -\f\*[B-Font]md5WithRSAEncryption\f[], -which stands for the MD5 message digest with RSA -encryption scheme. -The current NTP distribution supports -all the schemes in the OpenSSL library, including -those based on RSA and DSA digital signatures. -.sp \n(Ppu -.ne 2 - -NTP secure groups can be used to define cryptographic compartments -and security hierarchies. -It is important that every host -in the group be able to construct a certificate trail to one -or more trusted hosts in the same group. -Each group -host runs the Autokey protocol to obtain the certificates -for all hosts along the trail to one or more trusted hosts. -This requires the configuration file in all hosts to be -engineered so that, even under anticipated failure conditions, -the NTP subnet will form such that every group host can find -a trail to at least one trusted host. -.SS Naming and Addressing -It is important to note that Autokey does not use DNS to -resolve addresses, since DNS can't be completely trusted -until the name servers have synchronized clocks. -The cryptographic name used by Autokey to bind the host identity -credentials and cryptographic values must be independent -of interface, network and any other naming convention. -The name appears in the host certificate in either or both -the subject and issuer fields, so protection against -DNS compromise is essential. -.sp \n(Ppu -.ne 2 - -By convention, the name of an Autokey host is the name returned -by the Unix -\fCgethostname\fR(2)\f[] -system call or equivalent in other systems. -By the system design -model, there are no provisions to allow alternate names or aliases. -However, this is not to say that DNS aliases, different names -for each interface, etc., are constrained in any way. -.sp \n(Ppu -.ne 2 - -It is also important to note that Autokey verifies authenticity -using the host name, network address and public keys, -all of which are bound together by the protocol specifically -to deflect masquerade attacks. -For this reason Autokey -includes the source and destinatino IP addresses in message digest -computations and so the same addresses must be available -at both the server and client. -For this reason operation -with network address translation schemes is not possible. -This reflects the intended robust security model where government -and corporate NTP servers are operated outside firewall perimeters. -.SS Operation -A specific combination of authentication scheme (none, -symmetric key, public key) and identity scheme is called -a cryptotype, although not all combinations are compatible. -There may be management configurations where the clients, -servers and peers may not all support the same cryptotypes. -A secure NTPv4 subnet can be configured in many ways while -keeping in mind the principles explained above and -in this section. -Note however that some cryptotype -combinations may successfully interoperate with each other, -but may not represent good security practice. -.sp \n(Ppu -.ne 2 - -The cryptotype of an association is determined at the time -of mobilization, either at configuration time or some time -later when a message of appropriate cryptotype arrives. -When mobilized by a -\f\*[B-Font]server\f[] -or -\f\*[B-Font]peer\f[] -configuration command and no -\f\*[B-Font]key\f[] -or -\f\*[B-Font]autokey\f[] -subcommands are present, the association is not -authenticated; if the -\f\*[B-Font]key\f[] -subcommand is present, the association is authenticated -using the symmetric key ID specified; if the -\f\*[B-Font]autokey\f[] -subcommand is present, the association is authenticated -using Autokey. -.sp \n(Ppu -.ne 2 - -When multiple identity schemes are supported in the Autokey -protocol, the first message exchange determines which one is used. -The client request message contains bits corresponding -to which schemes it has available. -The server response message -contains bits corresponding to which schemes it has available. -Both server and client match the received bits with their own -and select a common scheme. -.sp \n(Ppu -.ne 2 - -Following the principle that time is a public value, -a server responds to any client packet that matches -its cryptotype capabilities. -Thus, a server receiving -an unauthenticated packet will respond with an unauthenticated -packet, while the same server receiving a packet of a cryptotype -it supports will respond with packets of that cryptotype. -However, unconfigured broadcast or manycast client -associations or symmetric passive associations will not be -mobilized unless the server supports a cryptotype compatible -with the first packet received. -By default, unauthenticated associations will not be mobilized -unless overridden in a decidedly dangerous way. -.sp \n(Ppu -.ne 2 - -Some examples may help to reduce confusion. -Client Alice has no specific cryptotype selected. -Server Bob has both a symmetric key file and minimal Autokey files. -Alice's unauthenticated messages arrive at Bob, who replies with -unauthenticated messages. -Cathy has a copy of Bob's symmetric -key file and has selected key ID 4 in messages to Bob. -Bob verifies the message with his key ID 4. -If it's the -same key and the message is verified, Bob sends Cathy a reply -authenticated with that key. -If verification fails, -Bob sends Cathy a thing called a crypto-NAK, which tells her -something broke. -She can see the evidence using the -\fCntpq\fR(1ntpqmdoc)\f[] -program. -.sp \n(Ppu -.ne 2 - -Denise has rolled her own host key and certificate. -She also uses one of the identity schemes as Bob. -She sends the first Autokey message to Bob and they -both dance the protocol authentication and identity steps. -If all comes out okay, Denise and Bob continue as described above. -.sp \n(Ppu -.ne 2 - -It should be clear from the above that Bob can support -all the girls at the same time, as long as he has compatible -authentication and identity credentials. -Now, Bob can act just like the girls in his own choice of servers; -he can run multiple configured associations with multiple different -servers (or the same server, although that might not be useful). -But, wise security policy might preclude some cryptotype -combinations; for instance, running an identity scheme -with one server and no authentication with another might not be wise. -.SS Key Management -The cryptographic values used by the Autokey protocol are -incorporated as a set of files generated by the -\fCntp-keygen\fR(1ntpkeygenmdoc)\f[] -utility program, including symmetric key, host key and -public certificate files, as well as sign key, identity parameters -and leapseconds files. -Alternatively, host and sign keys and -certificate files can be generated by the OpenSSL utilities -and certificates can be imported from public certificate -authorities. -Note that symmetric keys are necessary for the -\fCntpq\fR(1ntpqmdoc)\f[] -and -\fCntpdc\fR(1ntpdcmdoc)\f[] -utility programs. -The remaining files are necessary only for the -Autokey protocol. -.sp \n(Ppu -.ne 2 - -Certificates imported from OpenSSL or public certificate -authorities have certian limitations. -The certificate should be in ASN.1 syntax, X.509 Version 3 -format and encoded in PEM, which is the same format -used by OpenSSL. -The overall length of the certificate encoded -in ASN.1 must not exceed 1024 bytes. -The subject distinguished -name field (CN) is the fully qualified name of the host -on which it is used; the remaining subject fields are ignored. -The certificate extension fields must not contain either -a subject key identifier or a issuer key identifier field; -however, an extended key usage field for a trusted host must -contain the value -\f\*[B-Font]trustRoot\f[];. -Other extension fields are ignored. -.SS Authentication Commands -.TP 7 -.NOP \f\*[B-Font]autokey\f[] [\f\*[I-Font]logsec\f[]] -Specifies the interval between regenerations of the session key -list used with the Autokey protocol. -Note that the size of the key -list for each association depends on this interval and the current -poll interval. -The default value is 12 (4096 s or about 1.1 hours). -For poll intervals above the specified interval, a session key list -with a single entry will be regenerated for every message -sent. -.TP 7 -.NOP \f\*[B-Font]controlkey\f[] \f\*[I-Font]key\f[] -Specifies the key identifier to use with the -\fCntpq\fR(1ntpqmdoc)\f[] -utility, which uses the standard -protocol defined in RFC-1305. -The -\f\*[I-Font]key\f[] -argument is -the key identifier for a trusted key, where the value can be in the -range 1 to 65,534, inclusive. -.TP 7 -.NOP \f\*[B-Font]crypto\f[] [\f\*[B-Font]cert\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]leap\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]randfile\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]host\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]sign\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]gq\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]gqpar\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]iffpar\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]mvpar\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]pw\f[] \f\*[I-Font]password\f[]] -This command requires the OpenSSL library. -It activates public key -cryptography, selects the message digest and signature -encryption scheme and loads the required private and public -values described above. -If one or more files are left unspecified, -the default names are used as described above. -Unless the complete path and name of the file are specified, the -location of a file is relative to the keys directory specified -in the -\f\*[B-Font]keysdir\f[] -command or default -\fI/usr/local/etc\f[]. -Following are the subcommands: -.RS -.TP 7 -.NOP \f\*[B-Font]cert\f[] \f\*[I-Font]file\f[] -Specifies the location of the required host public certificate file. -This overrides the link -\fIntpkey_cert_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]gqpar\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional GQ parameters file. -This -overrides the link -\fIntpkey_gq_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]host\f[] \f\*[I-Font]file\f[] -Specifies the location of the required host key file. -This overrides -the link -\fIntpkey_key_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]iffpar\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional IFF parameters file.This -overrides the link -\fIntpkey_iff_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]leap\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional leapsecond file. -This overrides the link -\fIntpkey_leap\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]mvpar\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional MV parameters file. -This -overrides the link -\fIntpkey_mv_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]pw\f[] \f\*[I-Font]password\f[] -Specifies the password to decrypt files containing private keys and -identity parameters. -This is required only if these files have been -encrypted. -.TP 7 -.NOP \f\*[B-Font]randfile\f[] \f\*[I-Font]file\f[] -Specifies the location of the random seed file used by the OpenSSL -library. -The defaults are described in the main text above. -.TP 7 -.NOP \f\*[B-Font]sign\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional sign key file. -This overrides -the link -\fIntpkey_sign_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -If this file is -not found, the host key is also the sign key. -.RE -.TP 7 -.NOP \f\*[B-Font]keys\f[] \f\*[I-Font]keyfile\f[] -Specifies the complete path and location of the MD5 key file -containing the keys and key identifiers used by -\fCntpd\fR(1ntpdmdoc)\f[], -\fCntpq\fR(1ntpqmdoc)\f[] -and -\fCntpdc\fR(1ntpdcmdoc)\f[] -when operating with symmetric key cryptography. -This is the same operation as the -\f\*[B-Font]\-k\f[] -command line option. -.TP 7 -.NOP \f\*[B-Font]keysdir\f[] \f\*[I-Font]path\f[] -This command specifies the default directory path for -cryptographic keys, parameters and certificates. -The default is -\fI/usr/local/etc/\f[]. -.TP 7 -.NOP \f\*[B-Font]requestkey\f[] \f\*[I-Font]key\f[] -Specifies the key identifier to use with the -\fCntpdc\fR(1ntpdcmdoc)\f[] -utility program, which uses a -proprietary protocol specific to this implementation of -\fCntpd\fR(1ntpdmdoc)\f[]. -The -\f\*[I-Font]key\f[] -argument is a key identifier -for the trusted key, where the value can be in the range 1 to -65,534, inclusive. -.TP 7 -.NOP \f\*[B-Font]revoke\f[] \f\*[I-Font]logsec\f[] -Specifies the interval between re-randomization of certain -cryptographic values used by the Autokey scheme, as a power of 2 in -seconds. -These values need to be updated frequently in order to -deflect brute-force attacks on the algorithms of the scheme; -however, updating some values is a relatively expensive operation. -The default interval is 16 (65,536 s or about 18 hours). -For poll -intervals above the specified interval, the values will be updated -for every message sent. -.TP 7 -.NOP \f\*[B-Font]trustedkey\f[] \f\*[I-Font]key\f[] \f\*[I-Font]...\f[] -Specifies the key identifiers which are trusted for the -purposes of authenticating peers with symmetric key cryptography, -as well as keys used by the -\fCntpq\fR(1ntpqmdoc)\f[] -and -\fCntpdc\fR(1ntpdcmdoc)\f[] -programs. -The authentication procedures require that both the local -and remote servers share the same key and key identifier for this -purpose, although different keys can be used with different -servers. -The -\f\*[I-Font]key\f[] -arguments are 32-bit unsigned -integers with values from 1 to 65,534. -.PP -.SS Error Codes -The following error codes are reported via the NTP control -and monitoring protocol trap mechanism. -.TP 7 -.NOP 101 -(bad field format or length) -The packet has invalid version, length or format. -.TP 7 -.NOP 102 -(bad timestamp) -The packet timestamp is the same or older than the most recent received. -This could be due to a replay or a server clock time step. -.TP 7 -.NOP 103 -(bad filestamp) -The packet filestamp is the same or older than the most recent received. -This could be due to a replay or a key file generation error. -.TP 7 -.NOP 104 -(bad or missing public key) -The public key is missing, has incorrect format or is an unsupported type. -.TP 7 -.NOP 105 -(unsupported digest type) -The server requires an unsupported digest/signature scheme. -.TP 7 -.NOP 106 -(mismatched digest types) -Not used. -.TP 7 -.NOP 107 -(bad signature length) -The signature length does not match the current public key. -.TP 7 -.NOP 108 -(signature not verified) -The message fails the signature check. -It could be bogus or signed by a -different private key. -.TP 7 -.NOP 109 -(certificate not verified) -The certificate is invalid or signed with the wrong key. -.TP 7 -.NOP 110 -(certificate not verified) -The certificate is not yet valid or has expired or the signature could not -be verified. -.TP 7 -.NOP 111 -(bad or missing cookie) -The cookie is missing, corrupted or bogus. -.TP 7 -.NOP 112 -(bad or missing leapseconds table) -The leapseconds table is missing, corrupted or bogus. -.TP 7 -.NOP 113 -(bad or missing certificate) -The certificate is missing, corrupted or bogus. -.TP 7 -.NOP 114 -(bad or missing identity) -The identity key is missing, corrupt or bogus. -.PP -.SH Monitoring Support -\fCntpd\fR(1ntpdmdoc)\f[] -includes a comprehensive monitoring facility suitable -for continuous, long term recording of server and client -timekeeping performance. -See the -\f\*[B-Font]statistics\f[] -command below -for a listing and example of each type of statistics currently -supported. -Statistic files are managed using file generation sets -and scripts in the -\fI./scripts\f[] -directory of this distribution. -Using -these facilities and -UNIX -\fCcron\fR(8)\f[] -jobs, the data can be -automatically summarized and archived for retrospective analysis. -.SS Monitoring Commands -.TP 7 -.NOP \f\*[B-Font]statistics\f[] \f\*[I-Font]name\f[] \f\*[I-Font]...\f[] -Enables writing of statistics records. -Currently, eight kinds of -\f\*[I-Font]name\f[] -statistics are supported. -.RS -.TP 7 -.NOP \f\*[B-Font]clockstats\f[] -Enables recording of clock driver statistics information. -Each update -received from a clock driver appends a line of the following form to -the file generation set named -\f\*[B-Font]clockstats\f[]: -.br -.in +4 -.nf -49213 525.624 127.127.4.1 93 226 00:08:29.606 D -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and time -(seconds and fraction past UTC midnight). -The next field shows the -clock address in dotted-quad notation. -The final field shows the last -timecode received from the clock in decoded ASCII format, where -meaningful. -In some clock drivers a good deal of additional information -can be gathered and displayed as well. -See information specific to each -clock for further details. -.TP 7 -.NOP \f\*[B-Font]cryptostats\f[] -This option requires the OpenSSL cryptographic software library. -It -enables recording of cryptographic public key protocol information. -Each message received by the protocol module appends a line of the -following form to the file generation set named -\f\*[B-Font]cryptostats\f[]: -.br -.in +4 -.nf -49213 525.624 127.127.4.1 message -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and time -(seconds and fraction past UTC midnight). -The next field shows the peer -address in dotted-quad notation, The final message field includes the -message type and certain ancillary information. -See the -\fIAuthentication\f[] \fIOptions\f[] -section for further information. -.TP 7 -.NOP \f\*[B-Font]loopstats\f[] -Enables recording of loop filter statistics information. -Each -update of the local clock outputs a line of the following form to -the file generation set named -\f\*[B-Font]loopstats\f[]: -.br -.in +4 -.nf -50935 75440.031 0.000006019 13.778190 0.000351733 0.0133806 -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and -time (seconds and fraction past UTC midnight). -The next five fields -show time offset (seconds), frequency offset (parts per million \- -PPM), RMS jitter (seconds), Allan deviation (PPM) and clock -discipline time constant. -.TP 7 -.NOP \f\*[B-Font]peerstats\f[] -Enables recording of peer statistics information. -This includes -statistics records of all peers of a NTP server and of special -signals, where present and configured. -Each valid update appends a -line of the following form to the current element of a file -generation set named -\f\*[B-Font]peerstats\f[]: -.br -.in +4 -.nf -48773 10847.650 127.127.4.1 9714 \-0.001605376 0.000000000 0.001424877 0.000958674 -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and -time (seconds and fraction past UTC midnight). -The next two fields -show the peer address in dotted-quad notation and status, -respectively. -The status field is encoded in hex in the format -described in Appendix A of the NTP specification RFC 1305. -The final four fields show the offset, -delay, dispersion and RMS jitter, all in seconds. -.TP 7 -.NOP \f\*[B-Font]rawstats\f[] -Enables recording of raw-timestamp statistics information. -This -includes statistics records of all peers of a NTP server and of -special signals, where present and configured. -Each NTP message -received from a peer or clock driver appends a line of the -following form to the file generation set named -\f\*[B-Font]rawstats\f[]: -.br -.in +4 -.nf -50928 2132.543 128.4.1.1 128.4.1.20 3102453281.584327000 3102453281.58622800031 02453332.540806000 3102453332.541458000 -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and -time (seconds and fraction past UTC midnight). -The next two fields -show the remote peer or clock address followed by the local address -in dotted-quad notation. -The final four fields show the originate, -receive, transmit and final NTP timestamps in order. -The timestamp -values are as received and before processing by the various data -smoothing and mitigation algorithms. -.TP 7 -.NOP \f\*[B-Font]sysstats\f[] -Enables recording of ntpd statistics counters on a periodic basis. -Each -hour a line of the following form is appended to the file generation -set named -\f\*[B-Font]sysstats\f[]: -.br -.in +4 -.nf -50928 2132.543 36000 81965 0 9546 56 71793 512 540 10 147 -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and time -(seconds and fraction past UTC midnight). -The remaining ten fields show -the statistics counter values accumulated since the last generated -line. -.RS -.TP 7 -.NOP Time since restart \f\*[B-Font]36000\f[] -Time in hours since the system was last rebooted. -.TP 7 -.NOP Packets received \f\*[B-Font]81965\f[] -Total number of packets received. -.TP 7 -.NOP Packets processed \f\*[B-Font]0\f[] -Number of packets received in response to previous packets sent -.TP 7 -.NOP Current version \f\*[B-Font]9546\f[] -Number of packets matching the current NTP version. -.TP 7 -.NOP Previous version \f\*[B-Font]56\f[] -Number of packets matching the previous NTP version. -.TP 7 -.NOP Bad version \f\*[B-Font]71793\f[] -Number of packets matching neither NTP version. -.TP 7 -.NOP Access denied \f\*[B-Font]512\f[] -Number of packets denied access for any reason. -.TP 7 -.NOP Bad length or format \f\*[B-Font]540\f[] -Number of packets with invalid length, format or port number. -.TP 7 -.NOP Bad authentication \f\*[B-Font]10\f[] -Number of packets not verified as authentic. -.TP 7 -.NOP Rate exceeded \f\*[B-Font]147\f[] -Number of packets discarded due to rate limitation. -.RE -.TP 7 -.NOP \f\*[B-Font]statsdir\f[] \f\*[I-Font]directory_path\f[] -Indicates the full path of a directory where statistics files -should be created (see below). -This keyword allows -the (otherwise constant) -\f\*[B-Font]filegen\f[] -filename prefix to be modified for file generation sets, which -is useful for handling statistics logs. -.TP 7 -.NOP \f\*[B-Font]filegen\f[] \f\*[I-Font]name\f[] [\f\*[B-Font]file\f[] \f\*[I-Font]filename\f[]] [\f\*[B-Font]type\f[] \f\*[I-Font]typename\f[]] [\f\*[B-Font]link\f[] | \f\*[B-Font]nolink\f[]] [\f\*[B-Font]enable\f[] | \f\*[B-Font]disable\f[]] -Configures setting of generation file set name. -Generation -file sets provide a means for handling files that are -continuously growing during the lifetime of a server. -Server statistics are a typical example for such files. -Generation file sets provide access to a set of files used -to store the actual data. -At any time at most one element -of the set is being written to. -The type given specifies -when and how data will be directed to a new element of the set. -This way, information stored in elements of a file set -that are currently unused are available for administrational -operations without the risk of disturbing the operation of ntpd. -(Most important: they can be removed to free space for new data -produced.) -.sp \n(Ppu -.ne 2 - -Note that this command can be sent from the -\fCntpdc\fR(1ntpdcmdoc)\f[] -program running at a remote location. -.RS -.TP 7 -.NOP \f\*[B-Font]name\f[] -This is the type of the statistics records, as shown in the -\f\*[B-Font]statistics\f[] -command. -.TP 7 -.NOP \f\*[B-Font]file\f[] \f\*[I-Font]filename\f[] -This is the file name for the statistics records. -Filenames of set -members are built from three concatenated elements -\f\*[B-Font]prefix\f[], -\f\*[B-Font]filename\f[] -and -\f\*[B-Font]suffix\f[]: -.RS -.TP 7 -.NOP \f\*[B-Font]prefix\f[] -This is a constant filename path. -It is not subject to -modifications via the -\f\*[I-Font]filegen\f[] -option. -It is defined by the -server, usually specified as a compile-time constant. -It may, -however, be configurable for individual file generation sets -via other commands. -For example, the prefix used with -\f\*[I-Font]loopstats\f[] -and -\f\*[I-Font]peerstats\f[] -generation can be configured using the -\f\*[I-Font]statsdir\f[] -option explained above. -.TP 7 -.NOP \f\*[B-Font]filename\f[] -This string is directly concatenated to the prefix mentioned -above (no intervening -\[oq]/\[cq]). -This can be modified using -the file argument to the -\f\*[I-Font]filegen\f[] -statement. -No -\fI..\f[] -elements are -allowed in this component to prevent filenames referring to -parts outside the filesystem hierarchy denoted by -\f\*[I-Font]prefix\f[]. -.TP 7 -.NOP \f\*[B-Font]suffix\f[] -This part is reflects individual elements of a file set. -It is -generated according to the type of a file set. -.RE -.TP 7 -.NOP \f\*[B-Font]type\f[] \f\*[I-Font]typename\f[] -A file generation set is characterized by its type. -The following -types are supported: -.RS -.TP 7 -.NOP \f\*[B-Font]none\f[] -The file set is actually a single plain file. -.TP 7 -.NOP \f\*[B-Font]pid\f[] -One element of file set is used per incarnation of a ntpd -server. -This type does not perform any changes to file set -members during runtime, however it provides an easy way of -separating files belonging to different -\fCntpd\fR(1ntpdmdoc)\f[] -server incarnations. -The set member filename is built by appending a -\[oq]\&.\[cq] -to concatenated -\f\*[I-Font]prefix\f[] -and -\f\*[I-Font]filename\f[] -strings, and -appending the decimal representation of the process ID of the -\fCntpd\fR(1ntpdmdoc)\f[] -server process. -.TP 7 -.NOP \f\*[B-Font]day\f[] -One file generation set element is created per day. -A day is -defined as the period between 00:00 and 24:00 UTC. -The file set -member suffix consists of a -\[oq]\&.\[cq] -and a day specification in -the form -\f\*[B-Font]YYYYMMdd\f[]. -\f\*[B-Font]YYYY\f[] -is a 4-digit year number (e.g., 1992). -\f\*[B-Font]MM\f[] -is a two digit month number. -\f\*[B-Font]dd\f[] -is a two digit day number. -Thus, all information written at 10 December 1992 would end up -in a file named -\f\*[I-Font]prefix\f[] -\f\*[I-Font]filename\f[].19921210. -.TP 7 -.NOP \f\*[B-Font]week\f[] -Any file set member contains data related to a certain week of -a year. -The term week is defined by computing day-of-year -modulo 7. -Elements of such a file generation set are -distinguished by appending the following suffix to the file set -filename base: A dot, a 4-digit year number, the letter -\f\*[B-Font]W\f[], -and a 2-digit week number. -For example, information from January, -10th 1992 would end up in a file with suffix -.NOP. \f\*[I-Font]1992W1\f[]. -.TP 7 -.NOP \f\*[B-Font]month\f[] -One generation file set element is generated per month. -The -file name suffix consists of a dot, a 4-digit year number, and -a 2-digit month. -.TP 7 -.NOP \f\*[B-Font]year\f[] -One generation file element is generated per year. -The filename -suffix consists of a dot and a 4 digit year number. -.TP 7 -.NOP \f\*[B-Font]age\f[] -This type of file generation sets changes to a new element of -the file set every 24 hours of server operation. -The filename -suffix consists of a dot, the letter -\f\*[B-Font]a\f[], -and an 8-digit number. -This number is taken to be the number of seconds the server is -running at the start of the corresponding 24-hour period. -Information is only written to a file generation by specifying -\f\*[B-Font]enable\f[]; -output is prevented by specifying -\f\*[B-Font]disable\f[]. -.RE -.TP 7 -.NOP \f\*[B-Font]link\f[] | \f\*[B-Font]nolink\f[] -It is convenient to be able to access the current element of a file -generation set by a fixed name. -This feature is enabled by -specifying -\f\*[B-Font]link\f[] -and disabled using -\f\*[B-Font]nolink\f[]. -If link is specified, a -hard link from the current file set element to a file without -suffix is created. -When there is already a file with this name and -the number of links of this file is one, it is renamed appending a -dot, the letter -\f\*[B-Font]C\f[], -and the pid of the ntpd server process. -When the -number of links is greater than one, the file is unlinked. -This -allows the current file to be accessed by a constant name. -.TP 7 -.NOP \f\*[B-Font]enable\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]disable\f[] -Enables or disables the recording function. -.RE -.RE -.PP -.SH Access Control Support -The -\fCntpd\fR(1ntpdmdoc)\f[] -daemon implements a general purpose address/mask based restriction -list. -The list contains address/match entries sorted first -by increasing address values and and then by increasing mask values. -A match occurs when the bitwise AND of the mask and the packet -source address is equal to the bitwise AND of the mask and -address in the list. -The list is searched in order with the -last match found defining the restriction flags associated -with the entry. -Additional information and examples can be found in the -"Notes on Configuring NTP and Setting up a NTP Subnet" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.sp \n(Ppu -.ne 2 - -The restriction facility was implemented in conformance -with the access policies for the original NSFnet backbone -time servers. -Later the facility was expanded to deflect -cryptographic and clogging attacks. -While this facility may -be useful for keeping unwanted or broken or malicious clients -from congesting innocent servers, it should not be considered -an alternative to the NTP authentication facilities. -Source address based restrictions are easily circumvented -by a determined cracker. -.sp \n(Ppu -.ne 2 - -Clients can be denied service because they are explicitly -included in the restrict list created by the restrict command -or implicitly as the result of cryptographic or rate limit -violations. -Cryptographic violations include certificate -or identity verification failure; rate limit violations generally -result from defective NTP implementations that send packets -at abusive rates. -Some violations cause denied service -only for the offending packet, others cause denied service -for a timed period and others cause the denied service for -an indefinate period. -When a client or network is denied access -for an indefinate period, the only way at present to remove -the restrictions is by restarting the server. -.SS The Kiss-of-Death Packet -Ordinarily, packets denied service are simply dropped with no -further action except incrementing statistics counters. -Sometimes a -more proactive response is needed, such as a server message that -explicitly requests the client to stop sending and leave a message -for the system operator. -A special packet format has been created -for this purpose called the "kiss-of-death" (KoD) packet. -KoD packets have the leap bits set unsynchronized and stratum set -to zero and the reference identifier field set to a four-byte -ASCII code. -If the -\f\*[B-Font]noserve\f[] -or -\f\*[B-Font]notrust\f[] -flag of the matching restrict list entry is set, -the code is "DENY"; if the -\f\*[B-Font]limited\f[] -flag is set and the rate limit -is exceeded, the code is "RATE". -Finally, if a cryptographic violation occurs, the code is "CRYP". -.sp \n(Ppu -.ne 2 - -A client receiving a KoD performs a set of sanity checks to -minimize security exposure, then updates the stratum and -reference identifier peer variables, sets the access -denied (TEST4) bit in the peer flash variable and sends -a message to the log. -As long as the TEST4 bit is set, -the client will send no further packets to the server. -The only way at present to recover from this condition is -to restart the protocol at both the client and server. -This -happens automatically at the client when the association times out. -It will happen at the server only if the server operator cooperates. -.SS Access Control Commands -.TP 7 -.NOP \f\*[B-Font]discard\f[] [\f\*[B-Font]average\f[] \f\*[I-Font]avg\f[]] [\f\*[B-Font]minimum\f[] \f\*[I-Font]min\f[]] [\f\*[B-Font]monitor\f[] \f\*[I-Font]prob\f[]] -Set the parameters of the -\f\*[B-Font]limited\f[] -facility which protects the server from -client abuse. -The -\f\*[B-Font]average\f[] -subcommand specifies the minimum average packet -spacing, while the -\f\*[B-Font]minimum\f[] -subcommand specifies the minimum packet spacing. -Packets that violate these minima are discarded -and a kiss-o'-death packet returned if enabled. -The default -minimum average and minimum are 5 and 2, respectively. -The monitor subcommand specifies the probability of discard -for packets that overflow the rate-control window. -.TP 7 -.NOP \f\*[B-Font]restrict\f[] \f\*[B-Font]address\f[] [\f\*[B-Font]mask\f[] \f\*[I-Font]mask\f[]] [\f\*[I-Font]flag\f[] \f\*[I-Font]...\f[]] -The -\f\*[I-Font]address\f[] -argument expressed in -dotted-quad form is the address of a host or network. -Alternatively, the -\f\*[I-Font]address\f[] -argument can be a valid host DNS name. -The -\f\*[I-Font]mask\f[] -argument expressed in dotted-quad form defaults to -\f\*[B-Font]255.255.255.255\f[], -meaning that the -\f\*[I-Font]address\f[] -is treated as the address of an individual host. -A default entry (address -\f\*[B-Font]0.0.0.0\f[], -mask -\f\*[B-Font]0.0.0.0\f[]) -is always included and is always the first entry in the list. -Note that text string -\f\*[B-Font]default\f[], -with no mask option, may -be used to indicate the default entry. -In the current implementation, -\f\*[B-Font]flag\f[] -always -restricts access, i.e., an entry with no flags indicates that free -access to the server is to be given. -The flags are not orthogonal, -in that more restrictive flags will often make less restrictive -ones redundant. -The flags can generally be classed into two -categories, those which restrict time service and those which -restrict informational queries and attempts to do run-time -reconfiguration of the server. -One or more of the following flags -may be specified: -.RS -.TP 7 -.NOP \f\*[B-Font]ignore\f[] -Deny packets of all kinds, including -\fCntpq\fR(1ntpqmdoc)\f[] -and -\fCntpdc\fR(1ntpdcmdoc)\f[] -queries. -.TP 7 -.NOP \f\*[B-Font]kod\f[] -If this flag is set when an access violation occurs, a kiss-o'-death -(KoD) packet is sent. -KoD packets are rate limited to no more than one -per second. -If another KoD packet occurs within one second after the -last one, the packet is dropped. -.TP 7 -.NOP \f\*[B-Font]limited\f[] -Deny service if the packet spacing violates the lower limits specified -in the discard command. -A history of clients is kept using the -monitoring capability of -\fCntpd\fR(1ntpdmdoc)\f[]. -Thus, monitoring is always active as -long as there is a restriction entry with the -\f\*[B-Font]limited\f[] -flag. -.TP 7 -.NOP \f\*[B-Font]lowpriotrap\f[] -Declare traps set by matching hosts to be low priority. -The -number of traps a server can maintain is limited (the current limit -is 3). -Traps are usually assigned on a first come, first served -basis, with later trap requestors being denied service. -This flag -modifies the assignment algorithm by allowing low priority traps to -be overridden by later requests for normal priority traps. -.TP 7 -.NOP \f\*[B-Font]nomodify\f[] -Deny -\fCntpq\fR(1ntpqmdoc)\f[] -and -\fCntpdc\fR(1ntpdcmdoc)\f[] -queries which attempt to modify the state of the -server (i.e., run time reconfiguration). -Queries which return -information are permitted. -.TP 7 -.NOP \f\*[B-Font]noquery\f[] -Deny -\fCntpq\fR(1ntpqmdoc)\f[] -and -\fCntpdc\fR(1ntpdcmdoc)\f[] -queries. -Time service is not affected. -.TP 7 -.NOP \f\*[B-Font]nopeer\f[] -Deny packets which would result in mobilizing a new association. -This -includes broadcast and symmetric active packets when a configured -association does not exist. -.TP 7 -.NOP \f\*[B-Font]noserve\f[] -Deny all packets except -\fCntpq\fR(1ntpqmdoc)\f[] -and -\fCntpdc\fR(1ntpdcmdoc)\f[] -queries. -.TP 7 -.NOP \f\*[B-Font]notrap\f[] -Decline to provide mode 6 control message trap service to matching -hosts. -The trap service is a subsystem of the ntpdq control message -protocol which is intended for use by remote event logging programs. -.TP 7 -.NOP \f\*[B-Font]notrust\f[] -Deny service unless the packet is cryptographically authenticated. -.TP 7 -.NOP \f\*[B-Font]ntpport\f[] -This is actually a match algorithm modifier, rather than a -restriction flag. -Its presence causes the restriction entry to be -matched only if the source port in the packet is the standard NTP -UDP port (123). -Both -\f\*[B-Font]ntpport\f[] -and -\f\*[B-Font]non-ntpport\f[] -may -be specified. -The -\f\*[B-Font]ntpport\f[] -is considered more specific and -is sorted later in the list. -.TP 7 -.NOP \f\*[B-Font]version\f[] -Deny packets that do not match the current NTP version. -.RE -.sp \n(Ppu -.ne 2 - -Default restriction list entries with the flags ignore, interface, -ntpport, for each of the local host's interface addresses are -inserted into the table at startup to prevent the server -from attempting to synchronize to its own time. -A default entry is also always present, though if it is -otherwise unconfigured; no flags are associated -with the default entry (i.e., everything besides your own -NTP server is unrestricted). -.PP -.SH Automatic NTP Configuration Options -.SS Manycasting -Manycasting is a automatic discovery and configuration paradigm -new to NTPv4. -It is intended as a means for a multicast client -to troll the nearby network neighborhood to find cooperating -manycast servers, validate them using cryptographic means -and evaluate their time values with respect to other servers -that might be lurking in the vicinity. -The intended result is that each manycast client mobilizes -client associations with some number of the "best" -of the nearby manycast servers, yet automatically reconfigures -to sustain this number of servers should one or another fail. -.sp \n(Ppu -.ne 2 - -Note that the manycasting paradigm does not coincide -with the anycast paradigm described in RFC-1546, -which is designed to find a single server from a clique -of servers providing the same service. -The manycast paradigm is designed to find a plurality -of redundant servers satisfying defined optimality criteria. -.sp \n(Ppu -.ne 2 - -Manycasting can be used with either symmetric key -or public key cryptography. -The public key infrastructure (PKI) -offers the best protection against compromised keys -and is generally considered stronger, at least with relatively -large key sizes. -It is implemented using the Autokey protocol and -the OpenSSL cryptographic library available from -\f[C]http://www.openssl.org/\f[]. -The library can also be used with other NTPv4 modes -as well and is highly recommended, especially for broadcast modes. -.sp \n(Ppu -.ne 2 - -A persistent manycast client association is configured -using the manycastclient command, which is similar to the -server command but with a multicast (IPv4 class -\f\*[B-Font]D\f[] -or IPv6 prefix -\f\*[B-Font]FF\f[]) -group address. -The IANA has designated IPv4 address 224.1.1.1 -and IPv6 address FF05::101 (site local) for NTP. -When more servers are needed, it broadcasts manycast -client messages to this address at the minimum feasible rate -and minimum feasible time-to-live (TTL) hops, depending -on how many servers have already been found. -There can be as many manycast client associations -as different group address, each one serving as a template -for a future ephemeral unicast client/server association. -.sp \n(Ppu -.ne 2 - -Manycast servers configured with the -\f\*[B-Font]manycastserver\f[] -command listen on the specified group address for manycast -client messages. -Note the distinction between manycast client, -which actively broadcasts messages, and manycast server, -which passively responds to them. -If a manycast server is -in scope of the current TTL and is itself synchronized -to a valid source and operating at a stratum level equal -to or lower than the manycast client, it replies to the -manycast client message with an ordinary unicast server message. -.sp \n(Ppu -.ne 2 - -The manycast client receiving this message mobilizes -an ephemeral client/server association according to the -matching manycast client template, but only if cryptographically -authenticated and the server stratum is less than or equal -to the client stratum. -Authentication is explicitly required -and either symmetric key or public key (Autokey) can be used. -Then, the client polls the server at its unicast address -in burst mode in order to reliably set the host clock -and validate the source. -This normally results -in a volley of eight client/server at 2-s intervals -during which both the synchronization and cryptographic -protocols run concurrently. -Following the volley, -the client runs the NTP intersection and clustering -algorithms, which act to discard all but the "best" -associations according to stratum and synchronization -distance. -The surviving associations then continue -in ordinary client/server mode. -.sp \n(Ppu -.ne 2 - -The manycast client polling strategy is designed to reduce -as much as possible the volume of manycast client messages -and the effects of implosion due to near-simultaneous -arrival of manycast server messages. -The strategy is determined by the -\f\*[B-Font]manycastclient\f[], -\f\*[B-Font]tos\f[] -and -\f\*[B-Font]ttl\f[] -configuration commands. -The manycast poll interval is -normally eight times the system poll interval, -which starts out at the -\f\*[B-Font]minpoll\f[] -value specified in the -\f\*[B-Font]manycastclient\f[], -command and, under normal circumstances, increments to the -\f\*[B-Font]maxpolll\f[] -value specified in this command. -Initially, the TTL is -set at the minimum hops specified by the ttl command. -At each retransmission the TTL is increased until reaching -the maximum hops specified by this command or a sufficient -number client associations have been found. -Further retransmissions use the same TTL. -.sp \n(Ppu -.ne 2 - -The quality and reliability of the suite of associations -discovered by the manycast client is determined by the NTP -mitigation algorithms and the -\f\*[B-Font]minclock\f[] -and -\f\*[B-Font]minsane\f[] -values specified in the -\f\*[B-Font]tos\f[] -configuration command. -At least -\f\*[B-Font]minsane\f[] -candidate servers must be available and the mitigation -algorithms produce at least -\f\*[B-Font]minclock\f[] -survivors in order to synchronize the clock. -Byzantine agreement principles require at least four -candidates in order to correctly discard a single falseticker. -For legacy purposes, -\f\*[B-Font]minsane\f[] -defaults to 1 and -\f\*[B-Font]minclock\f[] -defaults to 3. -For manycast service -\f\*[B-Font]minsane\f[] -should be explicitly set to 4, assuming at least that -number of servers are available. -.sp \n(Ppu -.ne 2 - -If at least -\f\*[B-Font]minclock\f[] -servers are found, the manycast poll interval is immediately -set to eight times -\f\*[B-Font]maxpoll\f[]. -If less than -\f\*[B-Font]minclock\f[] -servers are found when the TTL has reached the maximum hops, -the manycast poll interval is doubled. -For each transmission -after that, the poll interval is doubled again until -reaching the maximum of eight times -\f\*[B-Font]maxpoll\f[]. -Further transmissions use the same poll interval and -TTL values. -Note that while all this is going on, -each client/server association found is operating normally -it the system poll interval. -.sp \n(Ppu -.ne 2 - -Administratively scoped multicast boundaries are normally -specified by the network router configuration and, -in the case of IPv6, the link/site scope prefix. -By default, the increment for TTL hops is 32 starting -from 31; however, the -\f\*[B-Font]ttl\f[] -configuration command can be -used to modify the values to match the scope rules. -.sp \n(Ppu -.ne 2 - -It is often useful to narrow the range of acceptable -servers which can be found by manycast client associations. -Because manycast servers respond only when the client -stratum is equal to or greater than the server stratum, -primary (stratum 1) servers fill find only primary servers -in TTL range, which is probably the most common objective. -However, unless configured otherwise, all manycast clients -in TTL range will eventually find all primary servers -in TTL range, which is probably not the most common -objective in large networks. -The -\f\*[B-Font]tos\f[] -command can be used to modify this behavior. -Servers with stratum below -\f\*[B-Font]floor\f[] -or above -\f\*[B-Font]ceiling\f[] -specified in the -\f\*[B-Font]tos\f[] -command are strongly discouraged during the selection -process; however, these servers may be temporally -accepted if the number of servers within TTL range is -less than -\f\*[B-Font]minclock\f[]. -.sp \n(Ppu -.ne 2 - -The above actions occur for each manycast client message, -which repeats at the designated poll interval. -However, once the ephemeral client association is mobilized, -subsequent manycast server replies are discarded, -since that would result in a duplicate association. -If during a poll interval the number of client associations -falls below -\f\*[B-Font]minclock\f[], -all manycast client prototype associations are reset -to the initial poll interval and TTL hops and operation -resumes from the beginning. -It is important to avoid -frequent manycast client messages, since each one requires -all manycast servers in TTL range to respond. -The result could well be an implosion, either minor or major, -depending on the number of servers in range. -The recommended value for -\f\*[B-Font]maxpoll\f[] -is 12 (4,096 s). -.sp \n(Ppu -.ne 2 - -It is possible and frequently useful to configure a host -as both manycast client and manycast server. -A number of hosts configured this way and sharing a common -group address will automatically organize themselves -in an optimum configuration based on stratum and -synchronization distance. -For example, consider an NTP -subnet of two primary servers and a hundred or more -dependent clients. -With two exceptions, all servers -and clients have identical configuration files including both -\f\*[B-Font]multicastclient\f[] -and -\f\*[B-Font]multicastserver\f[] -commands using, for instance, multicast group address -239.1.1.1. -The only exception is that each primary server -configuration file must include commands for the primary -reference source such as a GPS receiver. -.sp \n(Ppu -.ne 2 - -The remaining configuration files for all secondary -servers and clients have the same contents, except for the -\f\*[B-Font]tos\f[] -command, which is specific for each stratum level. -For stratum 1 and stratum 2 servers, that command is -not necessary. -For stratum 3 and above servers the -\f\*[B-Font]floor\f[] -value is set to the intended stratum number. -Thus, all stratum 3 configuration files are identical, -all stratum 4 files are identical and so forth. -.sp \n(Ppu -.ne 2 - -Once operations have stabilized in this scenario, -the primary servers will find the primary reference source -and each other, since they both operate at the same -stratum (1), but not with any secondary server or client, -since these operate at a higher stratum. -The secondary -servers will find the servers at the same stratum level. -If one of the primary servers loses its GPS receiver, -it will continue to operate as a client and other clients -will time out the corresponding association and -re-associate accordingly. -.sp \n(Ppu -.ne 2 - -Some administrators prefer to avoid running -\fCntpd\fR(1ntpdmdoc)\f[] -continuously and run either -\fCntpdate\fR(8)\f[] -or -\fCntpd\fR(1ntpdmdoc)\f[] -\f\*[B-Font]\-q\f[] -as a cron job. -In either case the servers must be -configured in advance and the program fails if none are -available when the cron job runs. -A really slick -application of manycast is with -\fCntpd\fR(1ntpdmdoc)\f[] -\f\*[B-Font]\-q\f[]. -The program wakes up, scans the local landscape looking -for the usual suspects, selects the best from among -the rascals, sets the clock and then departs. -Servers do not have to be configured in advance and -all clients throughout the network can have the same -configuration file. -.SS Manycast Interactions with Autokey -Each time a manycast client sends a client mode packet -to a multicast group address, all manycast servers -in scope generate a reply including the host name -and status word. -The manycast clients then run -the Autokey protocol, which collects and verifies -all certificates involved. -Following the burst interval -all but three survivors are cast off, -but the certificates remain in the local cache. -It often happens that several complete signing trails -from the client to the primary servers are collected in this way. -.sp \n(Ppu -.ne 2 - -About once an hour or less often if the poll interval -exceeds this, the client regenerates the Autokey key list. -This is in general transparent in client/server mode. -However, about once per day the server private value -used to generate cookies is refreshed along with all -manycast client associations. -In this case all -cryptographic values including certificates is refreshed. -If a new certificate has been generated since -the last refresh epoch, it will automatically revoke -all prior certificates that happen to be in the -certificate cache. -At the same time, the manycast -scheme starts all over from the beginning and -the expanding ring shrinks to the minimum and increments -from there while collecting all servers in scope. -.SS Manycast Options -.TP 7 -.NOP \f\*[B-Font]tos\f[] [\f\*[B-Font]ceiling\f[] \f\*[I-Font]ceiling\f[] | \f\*[B-Font]cohort\f[] { \f\*[B-Font]0\f[] | \f\*[B-Font]1\f[] } | \f\*[B-Font]floor\f[] \f\*[I-Font]floor\f[] | \f\*[B-Font]minclock\f[] \f\*[I-Font]minclock\f[] | \f\*[B-Font]minsane\f[] \f\*[I-Font]minsane\f[]] -This command affects the clock selection and clustering -algorithms. -It can be used to select the quality and -quantity of peers used to synchronize the system clock -and is most useful in manycast mode. -The variables operate -as follows: -.RS -.TP 7 -.NOP \f\*[B-Font]ceiling\f[] \f\*[I-Font]ceiling\f[] -Peers with strata above -\f\*[B-Font]ceiling\f[] -will be discarded if there are at least -\f\*[B-Font]minclock\f[] -peers remaining. -This value defaults to 15, but can be changed -to any number from 1 to 15. -.TP 7 -.NOP \f\*[B-Font]cohort\f[] {0 | 1 } -This is a binary flag which enables (0) or disables (1) -manycast server replies to manycast clients with the same -stratum level. -This is useful to reduce implosions where -large numbers of clients with the same stratum level -are present. -The default is to enable these replies. -.TP 7 -.NOP \f\*[B-Font]floor\f[] \f\*[I-Font]floor\f[] -Peers with strata below -\f\*[B-Font]floor\f[] -will be discarded if there are at least -\f\*[B-Font]minclock\f[] -peers remaining. -This value defaults to 1, but can be changed -to any number from 1 to 15. -.TP 7 -.NOP \f\*[B-Font]minclock\f[] \f\*[I-Font]minclock\f[] -The clustering algorithm repeatedly casts out outlyer -associations until no more than -\f\*[B-Font]minclock\f[] -associations remain. -This value defaults to 3, -but can be changed to any number from 1 to the number of -configured sources. -.TP 7 -.NOP \f\*[B-Font]minsane\f[] \f\*[I-Font]minsane\f[] -This is the minimum number of candidates available -to the clock selection algorithm in order to produce -one or more truechimers for the clustering algorithm. -If fewer than this number are available, the clock is -undisciplined and allowed to run free. -The default is 1 -for legacy purposes. -However, according to principles of -Byzantine agreement, -\f\*[B-Font]minsane\f[] -should be at least 4 in order to detect and discard -a single falseticker. -.RE -.TP 7 -.NOP \f\*[B-Font]ttl\f[] \f\*[I-Font]hop\f[] \f\*[I-Font]...\f[] -This command specifies a list of TTL values in increasing -order, up to 8 values can be specified. -In manycast mode these values are used in turn -in an expanding-ring search. -The default is eight -multiples of 32 starting at 31. -.PP -.SH Reference Clock Support -The NTP Version 4 daemon supports some three dozen different radio, -satellite and modem reference clocks plus a special pseudo-clock -used for backup or when no other clock source is available. -Detailed descriptions of individual device drivers and options can -be found in the -"Reference Clock Drivers" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -Additional information can be found in the pages linked -there, including the -"Debugging Hints for Reference Clock Drivers" -and -"How To Write a Reference Clock Driver" -pages -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -In addition, support for a PPS -signal is available as described in the -"Pulse-per-second (PPS) Signal Interfacing" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -Many -drivers support special line discipline/streams modules which can -significantly improve the accuracy using the driver. -These are -described in the -"Line Disciplines and Streams Drivers" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.sp \n(Ppu -.ne 2 - -A reference clock will generally (though not always) be a radio -timecode receiver which is synchronized to a source of standard -time such as the services offered by the NRC in Canada and NIST and -USNO in the US. -The interface between the computer and the timecode -receiver is device dependent, but is usually a serial port. -A -device driver specific to each reference clock must be selected and -compiled in the distribution; however, most common radio, satellite -and modem clocks are included by default. -Note that an attempt to -configure a reference clock when the driver has not been compiled -or the hardware port has not been appropriately configured results -in a scalding remark to the system log file, but is otherwise non -hazardous. -.sp \n(Ppu -.ne 2 - -For the purposes of configuration, -\fCntpd\fR(1ntpdmdoc)\f[] -treats -reference clocks in a manner analogous to normal NTP peers as much -as possible. -Reference clocks are identified by a syntactically -correct but invalid IP address, in order to distinguish them from -normal NTP peers. -Reference clock addresses are of the form -\f[C]127.127.\f[]\f\*[I-Font]t\f[].\f\*[I-Font]u\f[], -where -\f\*[I-Font]t\f[] -is an integer -denoting the clock type and -\f\*[I-Font]u\f[] -indicates the unit -number in the range 0-3. -While it may seem overkill, it is in fact -sometimes useful to configure multiple reference clocks of the same -type, in which case the unit numbers must be unique. -.sp \n(Ppu -.ne 2 - -The -\f\*[B-Font]server\f[] -command is used to configure a reference -clock, where the -\f\*[I-Font]address\f[] -argument in that command -is the clock address. -The -\f\*[B-Font]key\f[], -\f\*[B-Font]version\f[] -and -\f\*[B-Font]ttl\f[] -options are not used for reference clock support. -The -\f\*[B-Font]mode\f[] -option is added for reference clock support, as -described below. -The -\f\*[B-Font]prefer\f[] -option can be useful to -persuade the server to cherish a reference clock with somewhat more -enthusiasm than other reference clocks or peers. -Further -information on this option can be found in the -"Mitigation Rules and the prefer Keyword" -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]) -page. -The -\f\*[B-Font]minpoll\f[] -and -\f\*[B-Font]maxpoll\f[] -options have -meaning only for selected clock drivers. -See the individual clock -driver document pages for additional information. -.sp \n(Ppu -.ne 2 - -The -\f\*[B-Font]fudge\f[] -command is used to provide additional -information for individual clock drivers and normally follows -immediately after the -\f\*[B-Font]server\f[] -command. -The -\f\*[I-Font]address\f[] -argument specifies the clock address. -The -\f\*[B-Font]refid\f[] -and -\f\*[B-Font]stratum\f[] -options can be used to -override the defaults for the device. -There are two optional -device-dependent time offsets and four flags that can be included -in the -\f\*[B-Font]fudge\f[] -command as well. -.sp \n(Ppu -.ne 2 - -The stratum number of a reference clock is by default zero. -Since the -\fCntpd\fR(1ntpdmdoc)\f[] -daemon adds one to the stratum of each -peer, a primary server ordinarily displays an external stratum of -one. -In order to provide engineered backups, it is often useful to -specify the reference clock stratum as greater than zero. -The -\f\*[B-Font]stratum\f[] -option is used for this purpose. -Also, in cases -involving both a reference clock and a pulse-per-second (PPS) -discipline signal, it is useful to specify the reference clock -identifier as other than the default, depending on the driver. -The -\f\*[B-Font]refid\f[] -option is used for this purpose. -Except where noted, -these options apply to all clock drivers. -.SS Reference Clock Commands -.TP 7 -.NOP \f\*[B-Font]server\f[] \f[C]127.127.\f[]\f\*[I-Font]t\f[].\f\*[I-Font]u\f[] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]mode\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]int\f[]] -This command can be used to configure reference clocks in -special ways. -The options are interpreted as follows: -.RS -.TP 7 -.NOP \f\*[B-Font]prefer\f[] -Marks the reference clock as preferred. -All other things being -equal, this host will be chosen for synchronization among a set of -correctly operating hosts. -See the -"Mitigation Rules and the prefer Keyword" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]) -for further information. -.TP 7 -.NOP \f\*[B-Font]mode\f[] \f\*[I-Font]int\f[] -Specifies a mode number which is interpreted in a -device-specific fashion. -For instance, it selects a dialing -protocol in the ACTS driver and a device subtype in the -parse -drivers. -.TP 7 -.NOP \f\*[B-Font]minpoll\f[] \f\*[I-Font]int\f[] -.TP 7 -.NOP \f\*[B-Font]maxpoll\f[] \f\*[I-Font]int\f[] -These options specify the minimum and maximum polling interval -for reference clock messages, as a power of 2 in seconds -For -most directly connected reference clocks, both -\f\*[B-Font]minpoll\f[] -and -\f\*[B-Font]maxpoll\f[] -default to 6 (64 s). -For modem reference clocks, -\f\*[B-Font]minpoll\f[] -defaults to 10 (17.1 m) and -\f\*[B-Font]maxpoll\f[] -defaults to 14 (4.5 h). -The allowable range is 4 (16 s) to 17 (36.4 h) inclusive. -.RE -.TP 7 -.NOP \f\*[B-Font]fudge\f[] \f[C]127.127.\f[]\f\*[I-Font]t\f[].\f\*[I-Font]u\f[] [\f\*[B-Font]time1\f[] \f\*[I-Font]sec\f[]] [\f\*[B-Font]time2\f[] \f\*[I-Font]sec\f[]] [\f\*[B-Font]stratum\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]refid\f[] \f\*[I-Font]string\f[]] [\f\*[B-Font]mode\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]flag1\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[]] [\f\*[B-Font]flag2\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[]] [\f\*[B-Font]flag3\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[]] [\f\*[B-Font]flag4\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[]] -This command can be used to configure reference clocks in -special ways. -It must immediately follow the -\f\*[B-Font]server\f[] -command which configures the driver. -Note that the same capability -is possible at run time using the -\fCntpdc\fR(1ntpdcmdoc)\f[] -program. -The options are interpreted as -follows: -.RS -.TP 7 -.NOP \f\*[B-Font]time1\f[] \f\*[I-Font]sec\f[] -Specifies a constant to be added to the time offset produced by -the driver, a fixed-point decimal number in seconds. -This is used -as a calibration constant to adjust the nominal time offset of a -particular clock to agree with an external standard, such as a -precision PPS signal. -It also provides a way to correct a -systematic error or bias due to serial port or operating system -latencies, different cable lengths or receiver internal delay. -The -specified offset is in addition to the propagation delay provided -by other means, such as internal DIPswitches. -Where a calibration -for an individual system and driver is available, an approximate -correction is noted in the driver documentation pages. -Note: in order to facilitate calibration when more than one -radio clock or PPS signal is supported, a special calibration -feature is available. -It takes the form of an argument to the -\f\*[B-Font]enable\f[] -command described in -\fIMiscellaneous\f[] \fIOptions\f[] -page and operates as described in the -"Reference Clock Drivers" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.TP 7 -.NOP \f\*[B-Font]time2\f[] \f\*[I-Font]secs\f[] -Specifies a fixed-point decimal number in seconds, which is -interpreted in a driver-dependent way. -See the descriptions of -specific drivers in the -"Reference Clock Drivers" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.TP 7 -.NOP \f\*[B-Font]stratum\f[] \f\*[I-Font]int\f[] -Specifies the stratum number assigned to the driver, an integer -between 0 and 15. -This number overrides the default stratum number -ordinarily assigned by the driver itself, usually zero. -.TP 7 -.NOP \f\*[B-Font]refid\f[] \f\*[I-Font]string\f[] -Specifies an ASCII string of from one to four characters which -defines the reference identifier used by the driver. -This string -overrides the default identifier ordinarily assigned by the driver -itself. -.TP 7 -.NOP \f\*[B-Font]mode\f[] \f\*[I-Font]int\f[] -Specifies a mode number which is interpreted in a -device-specific fashion. -For instance, it selects a dialing -protocol in the ACTS driver and a device subtype in the -parse -drivers. -.TP 7 -.NOP \f\*[B-Font]flag1\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[] -.TP 7 -.NOP \f\*[B-Font]flag2\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[] -.TP 7 -.NOP \f\*[B-Font]flag3\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[] -.TP 7 -.NOP \f\*[B-Font]flag4\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[] -These four flags are used for customizing the clock driver. -The -interpretation of these values, and whether they are used at all, -is a function of the particular clock driver. -However, by -convention -\f\*[B-Font]flag4\f[] -is used to enable recording monitoring -data to the -\f\*[B-Font]clockstats\f[] -file configured with the -\f\*[B-Font]filegen\f[] -command. -Further information on the -\f\*[B-Font]filegen\f[] -command can be found in -\fIMonitoring\f[] \fIOptions\f[]. -.RE -.PP -.SH Miscellaneous Options -.TP 7 -.NOP \f\*[B-Font]broadcastdelay\f[] \f\*[I-Font]seconds\f[] -The broadcast and multicast modes require a special calibration -to determine the network delay between the local and remote -servers. -Ordinarily, this is done automatically by the initial -protocol exchanges between the client and server. -In some cases, -the calibration procedure may fail due to network or server access -controls, for example. -This command specifies the default delay to -be used under these circumstances. -Typically (for Ethernet), a -number between 0.003 and 0.007 seconds is appropriate. -The default -when this command is not used is 0.004 seconds. -.TP 7 -.NOP \f\*[B-Font]calldelay\f[] \f\*[I-Font]delay\f[] -This option controls the delay in seconds between the first and second -packets sent in burst or iburst mode to allow additional time for a modem -or ISDN call to complete. -.TP 7 -.NOP \f\*[B-Font]driftfile\f[] \f\*[I-Font]driftfile\f[] -This command specifies the complete path and name of the file used to -record the frequency of the local clock oscillator. -This is the same -operation as the -\f\*[B-Font]\-f\f[] -command line option. -If the file exists, it is read at -startup in order to set the initial frequency and then updated once per -hour with the current frequency computed by the daemon. -If the file name is -specified, but the file itself does not exist, the starts with an initial -frequency of zero and creates the file when writing it for the first time. -If this command is not given, the daemon will always start with an initial -frequency of zero. -.sp \n(Ppu -.ne 2 - -The file format consists of a single line containing a single -floating point number, which records the frequency offset measured -in parts-per-million (PPM). -The file is updated by first writing -the current drift value into a temporary file and then renaming -this file to replace the old version. -This implies that -\fCntpd\fR(1ntpdmdoc)\f[] -must have write permission for the directory the -drift file is located in, and that file system links, symbolic or -otherwise, should be avoided. -.TP 7 -.NOP \f\*[B-Font]enable\f[] [\f\*[B-Font]auth\f[] | \f\*[B-Font]bclient\f[] | \f\*[B-Font]calibrate\f[] | \f\*[B-Font]kernel\f[] | \f\*[B-Font]mode7\f[] | \f\*[B-Font]monitor\f[] | \f\*[B-Font]ntp\f[] | \f\*[B-Font]stats\f[]] -.TP 7 -.NOP \f\*[B-Font]disable\f[] [\f\*[B-Font]auth\f[] | \f\*[B-Font]bclient\f[] | \f\*[B-Font]calibrate\f[] | \f\*[B-Font]kernel\f[] | \f\*[B-Font]mode7\f[] | \f\*[B-Font]monitor\f[] | \f\*[B-Font]ntp\f[] | \f\*[B-Font]stats\f[]] -Provides a way to enable or disable various server options. -Flags not mentioned are unaffected. -Note that all of these flags -can be controlled remotely using the -\fCntpdc\fR(1ntpdcmdoc)\f[] -utility program. -.RS -.TP 7 -.NOP \f\*[B-Font]auth\f[] -Enables the server to synchronize with unconfigured peers only if the -peer has been correctly authenticated using either public key or -private key cryptography. -The default for this flag is -\f\*[B-Font]enable\f[]. -.TP 7 -.NOP \f\*[B-Font]bclient\f[] -Enables the server to listen for a message from a broadcast or -multicast server, as in the -\f\*[B-Font]multicastclient\f[] -command with default -address. -The default for this flag is -\f\*[B-Font]disable\f[]. -.TP 7 -.NOP \f\*[B-Font]calibrate\f[] -Enables the calibrate feature for reference clocks. -The default for -this flag is -\f\*[B-Font]disable\f[]. -.TP 7 -.NOP \f\*[B-Font]kernel\f[] -Enables the kernel time discipline, if available. -The default for this -flag is -\f\*[B-Font]enable\f[] -if support is available, otherwise -\f\*[B-Font]disable\f[]. -.TP 7 -.NOP \f\*[B-Font]mode7\f[] -Enables processing of NTP mode 7 implementation-specific requests -which are used by the deprecated -\fCntpdc\fR(1ntpdcmdoc)\f[] -program. -The default for this flag is disable. -This flag is excluded from runtime configuration using -\fCntpq\fR(1ntpqmdoc)\f[]. -The -\fCntpq\fR(1ntpqmdoc)\f[] -program provides the same capabilities as -\fCntpdc\fR(1ntpdcmdoc)\f[] -using standard mode 6 requests. -.TP 7 -.NOP \f\*[B-Font]monitor\f[] -Enables the monitoring facility. -See the -\fCntpdc\fR(1ntpdcmdoc)\f[] -program -and the -\f\*[B-Font]monlist\f[] -command or further information. -The -default for this flag is -\f\*[B-Font]enable\f[]. -.TP 7 -.NOP \f\*[B-Font]ntp\f[] -Enables time and frequency discipline. -In effect, this switch opens and -closes the feedback loop, which is useful for testing. -The default for -this flag is -\f\*[B-Font]enable\f[]. -.TP 7 -.NOP \f\*[B-Font]stats\f[] -Enables the statistics facility. -See the -\fIMonitoring\f[] \fIOptions\f[] -section for further information. -The default for this flag is -\f\*[B-Font]disable\f[]. -.RE -.TP 7 -.NOP \f\*[B-Font]includefile\f[] \f\*[I-Font]includefile\f[] -This command allows additional configuration commands -to be included from a separate file. -Include files may -be nested to a depth of five; upon reaching the end of any -include file, command processing resumes in the previous -configuration file. -This option is useful for sites that run -\fCntpd\fR(1ntpdmdoc)\f[] -on multiple hosts, with (mostly) common options (e.g., a -restriction list). -.TP 7 -.NOP \f\*[B-Font]logconfig\f[] \f\*[I-Font]configkeyword\f[] -This command controls the amount and type of output written to -the system -\fCsyslog\fR(3)\f[] -facility or the alternate -\f\*[B-Font]logfile\f[] -log file. -By default, all output is turned on. -All -\f\*[I-Font]configkeyword\f[] -keywords can be prefixed with -\[oq]=\[cq], -\[oq]+\[cq] -and -\[oq]\-\[cq], -where -\[oq]=\[cq] -sets the -\fCsyslog\fR(3)\f[] -priority mask, -\[oq]+\[cq] -adds and -\[oq]\-\[cq] -removes -messages. -\fCsyslog\fR(3)\f[] -messages can be controlled in four -classes -(\f\*[B-Font]clock\f[], \f\*[B-Font]peer\f[], \f\*[B-Font]sys\f[] and \f\*[B-Font]sync\f[]). -Within these classes four types of messages can be -controlled: informational messages -(\f\*[B-Font]info\f[]), -event messages -(\f\*[B-Font]events\f[]), -statistics messages -(\f\*[B-Font]statistics\f[]) -and -status messages -(\f\*[B-Font]status\f[]). -.sp \n(Ppu -.ne 2 - -Configuration keywords are formed by concatenating the message class with -the event class. -The -\f\*[B-Font]all\f[] -prefix can be used instead of a message class. -A -message class may also be followed by the -\f\*[B-Font]all\f[] -keyword to enable/disable all -messages of the respective message class.Thus, a minimal log configuration -could look like this: -.br -.in +4 -.nf -logconfig =syncstatus +sysevents -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -This would just list the synchronizations state of -\fCntpd\fR(1ntpdmdoc)\f[] -and the major system events. -For a simple reference server, the -following minimum message configuration could be useful: -.br -.in +4 -.nf -logconfig =syncall +clockall -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -This configuration will list all clock information and -synchronization information. -All other events and messages about -peers, system events and so on is suppressed. -.TP 7 -.NOP \f\*[B-Font]logfile\f[] \f\*[I-Font]logfile\f[] -This command specifies the location of an alternate log file to -be used instead of the default system -\fCsyslog\fR(3)\f[] -facility. -This is the same operation as the \-l command line option. -.TP 7 -.NOP \f\*[B-Font]setvar\f[] \f\*[I-Font]variable\f[] [\f\*[B-Font]default\f[]] -This command adds an additional system variable. -These -variables can be used to distribute additional information such as -the access policy. -If the variable of the form -\fIname\f[]\fI=\f[]\f\*[I-Font]value\f[] -is followed by the -\f\*[B-Font]default\f[] -keyword, the -variable will be listed as part of the default system variables -(\fCntpq\fR(1ntpqmdoc)\f[] \f\*[B-Font]rv\f[] command)). -These additional variables serve -informational purposes only. -They are not related to the protocol -other that they can be listed. -The known protocol variables will -always override any variables defined via the -\f\*[B-Font]setvar\f[] -mechanism. -There are three special variables that contain the names -of all variable of the same group. -The -\fIsys_var_list\f[] -holds -the names of all system variables. -The -\fIpeer_var_list\f[] -holds -the names of all peer variables and the -\fIclock_var_list\f[] -holds the names of the reference clock variables. -.TP 7 -.NOP \f\*[B-Font]tinker\f[] [\f\*[B-Font]allan\f[] \f\*[I-Font]allan\f[] | \f\*[B-Font]dispersion\f[] \f\*[I-Font]dispersion\f[] | \f\*[B-Font]freq\f[] \f\*[I-Font]freq\f[] | \f\*[B-Font]huffpuff\f[] \f\*[I-Font]huffpuff\f[] | \f\*[B-Font]panic\f[] \f\*[I-Font]panic\f[] | \f\*[B-Font]step\f[] \f\*[I-Font]srep\f[] | \f\*[B-Font]stepout\f[] \f\*[I-Font]stepout\f[]] -This command can be used to alter several system variables in -very exceptional circumstances. -It should occur in the -configuration file before any other configuration options. -The -default values of these variables have been carefully optimized for -a wide range of network speeds and reliability expectations. -In -general, they interact in intricate ways that are hard to predict -and some combinations can result in some very nasty behavior. -Very -rarely is it necessary to change the default values; but, some -folks cannot resist twisting the knobs anyway and this command is -for them. -Emphasis added: twisters are on their own and can expect -no help from the support group. -.sp \n(Ppu -.ne 2 - -The variables operate as follows: -.RS -.TP 7 -.NOP \f\*[B-Font]allan\f[] \f\*[I-Font]allan\f[] -The argument becomes the new value for the minimum Allan -intercept, which is a parameter of the PLL/FLL clock discipline -algorithm. -The value in log2 seconds defaults to 7 (1024 s), which is also the lower -limit. -.TP 7 -.NOP \f\*[B-Font]dispersion\f[] \f\*[I-Font]dispersion\f[] -The argument becomes the new value for the dispersion increase rate, -normally .000015 s/s. -.TP 7 -.NOP \f\*[B-Font]freq\f[] \f\*[I-Font]freq\f[] -The argument becomes the initial value of the frequency offset in -parts-per-million. -This overrides the value in the frequency file, if -present, and avoids the initial training state if it is not. -.TP 7 -.NOP \f\*[B-Font]huffpuff\f[] \f\*[I-Font]huffpuff\f[] -The argument becomes the new value for the experimental -huff-n'-puff filter span, which determines the most recent interval -the algorithm will search for a minimum delay. -The lower limit is -900 s (15 m), but a more reasonable value is 7200 (2 hours). -There -is no default, since the filter is not enabled unless this command -is given. -.TP 7 -.NOP \f\*[B-Font]panic\f[] \f\*[I-Font]panic\f[] -The argument is the panic threshold, normally 1000 s. -If set to zero, -the panic sanity check is disabled and a clock offset of any value will -be accepted. -.TP 7 -.NOP \f\*[B-Font]step\f[] \f\*[I-Font]step\f[] -The argument is the step threshold, which by default is 0.128 s. -It can -be set to any positive number in seconds. -If set to zero, step -adjustments will never occur. -Note: The kernel time discipline is -disabled if the step threshold is set to zero or greater than the -default. -.TP 7 -.NOP \f\*[B-Font]stepout\f[] \f\*[I-Font]stepout\f[] -The argument is the stepout timeout, which by default is 900 s. -It can -be set to any positive number in seconds. -If set to zero, the stepout -pulses will not be suppressed. -.RE -.TP 7 -.NOP \f\*[B-Font]rlimit\f[] [\f\*[B-Font]memlock\f[] \f\*[I-Font]Nmegabytes\f[] | \f\*[B-Font]stacksize\f[] \f\*[I-Font]N4kPages\f[] \f\*[B-Font]filenum\f[] \f\*[I-Font]Nfiledescriptors\f[]] -.RS -.TP 7 -.NOP \f\*[B-Font]memlock\f[] \f\*[I-Font]Nmegabytes\f[] -Specify the number of megabytes of memory that can be allocated. -Probably only available under Linux, this option is useful -when dropping root (the -\f\*[B-Font]\-i\f[] -option). -The default is 32 megabytes. Setting this to zero will prevent any attemp to lock memory. -.TP 7 -.NOP \f\*[B-Font]stacksize\f[] \f\*[I-Font]N4kPages\f[] -Specifies the maximum size of the process stack on systems with the -.TP 7 -.NOP \f\*[B-Font]filenum\f[] \f\*[I-Font]Nfiledescriptors\f[] -Specifies the maximum number of file descriptors ntpd may have open at once. Defaults to the system default. -\fBmlockall\fR()\f[] -function. -Defaults to 50 4k pages (200 4k pages in OpenBSD). -.RE -.TP 7 -.NOP \f\*[B-Font]trap\f[] \f\*[I-Font]host_address\f[] [\f\*[B-Font]port\f[] \f\*[I-Font]port_number\f[]] [\f\*[B-Font]interface\f[] \f\*[I-Font]interface_address\f[]] -This command configures a trap receiver at the given host -address and port number for sending messages with the specified -local interface address. -If the port number is unspecified, a value -of 18447 is used. -If the interface address is not specified, the -message is sent with a source address of the local interface the -message is sent through. -Note that on a multihomed host the -interface used may vary from time to time with routing changes. -.sp \n(Ppu -.ne 2 - -The trap receiver will generally log event messages and other -information from the server in a log file. -While such monitor -programs may also request their own trap dynamically, configuring a -trap receiver will ensure that no messages are lost when the server -is started. -.TP 7 -.NOP \f\*[B-Font]hop\f[] \f\*[I-Font]...\f[] -This command specifies a list of TTL values in increasing order, up to 8 -values can be specified. -In manycast mode these values are used in turn in -an expanding-ring search. -The default is eight multiples of 32 starting at -31. -.PP -.SH "OPTIONS" -.TP -.NOP \f\*[B-Font]\-\-help\f[] -Display usage information and exit. -.TP -.NOP \f\*[B-Font]\-\-more-help\f[] -Pass the extended usage information through a pager. -.TP -.NOP \f\*[B-Font]\-\-version\f[] [{\f\*[I-Font]v|c|n\f[]}] -Output version of program and exit. The default mode is `v', a simple -version. The `c' mode will print copyright information and `n' will -print the full copyright notice. -.PP -.SH "OPTION PRESETS" -Any option that is not marked as \fInot presettable\fP may be preset -by loading values from environment variables named: -.nf - \fBNTP_CONF_\fP or \fBNTP_CONF\fP -.fi -.ad -.TH ntp.conf 5man "02 Apr 2014" "4.2.7p439" "File Formats" -.\" -.\" EDIT THIS FILE WITH CAUTION (/tmp/.ag-QxaqsZ/ag-CyaqrZ) -.\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:09 AM by AutoGen 5.18.3pre18 -.\" From the definitions ntp.conf.def -.\" and the template file agman-cmd.tpl -.SH NAME -\f\*[B-Font]ntp.conf\fP ntp.conf -\- Network Time Protocol (NTP) daemon configuration file format -cvt_prog='/usr/local/gnu/share/autogen/texi2man' -cvt_prog=`cd \`dirname "$cvt_prog"\` >/dev/null && pwd - `/`basename "$cvt_prog"` -cd $tmp_dir -test \-x "$cvt_prog" || die "'$cvt_prog' is not executable" -{ - list='synopsis description options option-presets' - for f in $list ; do cat $f ; echo ; done - rm \-f $list name - list='implementation-notes environment files examples exit-status errors - compatibility see-also conforming-to history authors copyright bugs - notes' - for f in $list ; do cat $f ; echo ; done > .end-doc - rm \-f $list - list=`ls \-1 *`' .end-doc' - for f in $list ; do cat $f ; echo ; done - rm \-f $list -} 1>.doc 2>/dev/null -/opt/csw/bin/ggrep \-E \-v '^[ ]*$' .doc | $cvt_prog -.SH "ENVIRONMENT" -See \fBOPTION PRESETS\fP for configuration environment variables. -.SH FILES -.TP 15 -.NOP \fI/etc/ntp.conf\f[] -the default name of the configuration file -.br -.ns -.TP 15 -.NOP \fIntp.keys\f[] -private MD5 keys -.br -.ns -.TP 15 -.NOP \fIntpkey\f[] -RSA private key -.br -.ns -.TP 15 -.NOP \fIntpkey_\f[]\f\*[I-Font]host\f[] -RSA public key -.br -.ns -.TP 15 -.NOP \fIntp_dh\f[] -Diffie-Hellman agreement parameters -.PP -.SH "EXIT STATUS" -One of the following exit values will be returned: -.TP -.NOP 0 " (EXIT_SUCCESS)" -Successful program execution. -.TP -.NOP 1 " (EXIT_FAILURE)" -The operation failed or the command syntax was not valid. -.TP -.NOP 70 " (EX_SOFTWARE)" -libopts had an internal operational error. Please report -it to autogen-users@lists.sourceforge.net. Thank you. -.PP -.SH "SEE ALSO" -\fCntpd\fR(1ntpdmdoc)\f[], -\fCntpdc\fR(1ntpdcmdoc)\f[], -\fCntpq\fR(1ntpqmdoc)\f[] -.sp \n(Ppu -.ne 2 - -In addition to the manual pages provided, -comprehensive documentation is available on the world wide web -at -\f[C]http://www.ntp.org/\f[]. -A snapshot of this documentation is available in HTML format in -\fI/usr/share/doc/ntp\f[]. -David L. Mills, -\fINetwork Time Protocol (Version 4)\fR, -RFC5905 -.PP - -.SH "AUTHORS" -The University of Delaware -.SH "COPYRIGHT" -Copyright (C) 1970-2013 The University of Delaware all rights reserved. -This program is released under the terms of the NTP license, . -.SH BUGS -The syntax checking is not picky; some combinations of -ridiculous and even hilarious options and modes may not be -detected. -.sp \n(Ppu -.ne 2 - -The -\fIntpkey_\f[]\f\*[I-Font]host\f[] -files are really digital -certificates. -These should be obtained via secure directory -services when they become universally available. -.sp \n(Ppu -.ne 2 - -Please send bug reports to: http://bugs.ntp.org, bugs@ntp.org -.SH NOTES -This document was derived from FreeBSD. -.sp \n(Ppu -.ne 2 - -This manual page was \fIAutoGen\fP-erated from the \fBntp.conf\fP -option definitions. diff --git a/ntpd/ntp.conf.5mdoc b/ntpd/ntp.conf.5mdoc index 17bcabb12..2a89470b7 100644 --- a/ntpd/ntp.conf.5mdoc +++ b/ntpd/ntp.conf.5mdoc @@ -1,9 +1,9 @@ -.Dd April 2 2014 +.Dd April 9 2014 .Dt NTP_CONF 5mdoc File Formats .Os .\" EDIT THIS FILE WITH CAUTION (ntp.mdoc) .\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:43 AM by AutoGen 5.18.3pre18 +.\" It has been AutoGen-ed April 9, 2014 at 10:03:46 AM by AutoGen 5.18.3pre18 .\" From the definitions ntp.conf.def .\" and the template file agmdoc-cmd.tpl .Sh NAME diff --git a/ntpd/ntp.conf.html b/ntpd/ntp.conf.html index 51aaa3375..0dbb633eb 100644 --- a/ntpd/ntp.conf.html +++ b/ntpd/ntp.conf.html @@ -33,7 +33,7 @@ Up: (dir)

This document describes the configuration file for the NTP Project's ntpd program. -

This document applies to version 4.2.7p439 of ntp.conf. +

This document applies to version 4.2.7p440 of ntp.conf.

Short Contents

diff --git a/ntpd/ntp.conf.man.in b/ntpd/ntp.conf.man.in index e1438fa81..8b1378917 100644 --- a/ntpd/ntp.conf.man.in +++ b/ntpd/ntp.conf.man.in @@ -1,3020 +1 @@ -.de1 NOP -. it 1 an-trap -. if \\n[.$] \,\\$*\/ -.. -.ie t \ -.ds B-Font [CB] -.ds I-Font [CI] -.ds R-Font [CR] -.el \ -.ds B-Font B -.ds I-Font I -.ds R-Font R -.TH ntp.conf 5 "02 Apr 2014" "4.2.7p439" "File Formats" -.\" -.\" EDIT THIS FILE WITH CAUTION (/tmp/.ag-QxaqsZ/ag-CyaqrZ) -.\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:09 AM by AutoGen 5.18.3pre18 -.\" From the definitions ntp.conf.def -.\" and the template file agman-cmd.tpl -.SH NAME -\f\*[B-Font]ntp.conf\fP -\- Network Time Protocol (NTP) daemon configuration file format -.SH SYNOPSIS -\f\*[B-Font]ntp.conf\fP -[\f\*[B-Font]\-\-option-name\f[]] -[\f\*[B-Font]\-\-option-name\f[] \f\*[I-Font]value\f[]] -.sp \n(Ppu -.ne 2 -All arguments must be options. -.sp \n(Ppu -.ne 2 - -.SH DESCRIPTION -The -\f\*[B-Font]ntp.conf\fP -configuration file is read at initial startup by the -\fCntpd\fR(@NTPD_MS@)\f[] -daemon in order to specify the synchronization sources, -modes and other related information. -Usually, it is installed in the -\fI/etc\f[] -directory, -but could be installed elsewhere -(see the daemon's -\f\*[B-Font]\-c\f[] -command line option). -.sp \n(Ppu -.ne 2 - -The file format is similar to other -UNIX -configuration files. -Comments begin with a -\[oq]#\[cq] -character and extend to the end of the line; -blank lines are ignored. -Configuration commands consist of an initial keyword -followed by a list of arguments, -some of which may be optional, separated by whitespace. -Commands may not be continued over multiple lines. -Arguments may be host names, -host addresses written in numeric, dotted-quad form, -integers, floating point numbers (when specifying times in seconds) -and text strings. -.sp \n(Ppu -.ne 2 - -The rest of this page describes the configuration and control options. -The -"Notes on Configuring NTP and Setting up an NTP Subnet" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]) -contains an extended discussion of these options. -In addition to the discussion of general -\fIConfiguration\f[] \fIOptions\f[], -there are sections describing the following supported functionality -and the options used to control it: -.IP \fB\(bu\fP 2 -\fIAuthentication\f[] \fISupport\f[] -.IP \fB\(bu\fP 2 -\fIMonitoring\f[] \fISupport\f[] -.IP \fB\(bu\fP 2 -\fIAccess\f[] \fIControl\f[] \fISupport\f[] -.IP \fB\(bu\fP 2 -\fIAutomatic\f[] \fINTP\f[] \fIConfiguration\f[] \fIOptions\f[] -.IP \fB\(bu\fP 2 -\fIReference\f[] \fIClock\f[] \fISupport\f[] -.IP \fB\(bu\fP 2 -\fIMiscellaneous\f[] \fIOptions\f[] -.PP -.sp \n(Ppu -.ne 2 - -Following these is a section describing -\fIMiscellaneous\f[] \fIOptions\f[]. -While there is a rich set of options available, -the only required option is one or more -\f\*[B-Font]pool\f[], -\f\*[B-Font]server\f[], -\f\*[B-Font]peer\f[], -\f\*[B-Font]broadcast\f[] -or -\f\*[B-Font]manycastclient\f[] -commands. -.SH Configuration Support -Following is a description of the configuration commands in -NTPv4. -These commands have the same basic functions as in NTPv3 and -in some cases new functions and new arguments. -There are two -classes of commands, configuration commands that configure a -persistent association with a remote server or peer or reference -clock, and auxiliary commands that specify environmental variables -that control various related operations. -.SS Configuration Commands -The various modes are determined by the command keyword and the -type of the required IP address. -Addresses are classed by type as -(s) a remote server or peer (IPv4 class A, B and C), (b) the -broadcast address of a local interface, (m) a multicast address (IPv4 -class D), or (r) a reference clock address (127.127.x.x). -Note that -only those options applicable to each command are listed below. -Use -of options not listed may not be caught as an error, but may result -in some weird and even destructive behavior. -.sp \n(Ppu -.ne 2 - -If the Basic Socket Interface Extensions for IPv6 (RFC-2553) -is detected, support for the IPv6 address family is generated -in addition to the default support of the IPv4 address family. -In a few cases, including the reslist billboard generated -by ntpdc, IPv6 addresses are automatically generated. -IPv6 addresses can be identified by the presence of colons -\*[Lq]\&:\*[Rq] -in the address field. -IPv6 addresses can be used almost everywhere where -IPv4 addresses can be used, -with the exception of reference clock addresses, -which are always IPv4. -.sp \n(Ppu -.ne 2 - -Note that in contexts where a host name is expected, a -\f\*[B-Font]\-4\f[] -qualifier preceding -the host name forces DNS resolution to the IPv4 namespace, -while a -\f\*[B-Font]\-6\f[] -qualifier forces DNS resolution to the IPv6 namespace. -See IPv6 references for the -equivalent classes for that address family. -.TP 7 -.NOP \f\*[B-Font]pool\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]burst\f[]] [\f\*[B-Font]iburst\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] -.TP 7 -.NOP \f\*[B-Font]server\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]\&|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]burst\f[]] [\f\*[B-Font]iburst\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] -.TP 7 -.NOP \f\*[B-Font]peer\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]\&|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] -.TP 7 -.NOP \f\*[B-Font]broadcast\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]\&|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]ttl\f[] \f\*[I-Font]ttl\f[]] -.TP 7 -.NOP \f\*[B-Font]manycastclient\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]\&|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] [\f\*[B-Font]ttl\f[] \f\*[I-Font]ttl\f[]] -.PP -.sp \n(Ppu -.ne 2 - -These five commands specify the time server name or address to -be used and the mode in which to operate. -The -\f\*[I-Font]address\f[] -can be -either a DNS name or an IP address in dotted-quad notation. -Additional information on association behavior can be found in the -"Association Management" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.TP 7 -.NOP \f\*[B-Font]pool\f[] -For type s addresses, this command mobilizes a persistent -client mode association with a number of remote servers. -In this mode the local clock can synchronized to the -remote server, but the remote server can never be synchronized to -the local clock. -.TP 7 -.NOP \f\*[B-Font]server\f[] -For type s and r addresses, this command mobilizes a persistent -client mode association with the specified remote server or local -radio clock. -In this mode the local clock can synchronized to the -remote server, but the remote server can never be synchronized to -the local clock. -This command should -\fInot\f[] -be used for type -b or m addresses. -.TP 7 -.NOP \f\*[B-Font]peer\f[] -For type s addresses (only), this command mobilizes a -persistent symmetric-active mode association with the specified -remote peer. -In this mode the local clock can be synchronized to -the remote peer or the remote peer can be synchronized to the local -clock. -This is useful in a network of servers where, depending on -various failure scenarios, either the local or remote peer may be -the better source of time. -This command should NOT be used for type -b, m or r addresses. -.TP 7 -.NOP \f\*[B-Font]broadcast\f[] -For type b and m addresses (only), this -command mobilizes a persistent broadcast mode association. -Multiple -commands can be used to specify multiple local broadcast interfaces -(subnets) and/or multiple multicast groups. -Note that local -broadcast messages go only to the interface associated with the -subnet specified, but multicast messages go to all interfaces. -In broadcast mode the local server sends periodic broadcast -messages to a client population at the -\f\*[I-Font]address\f[] -specified, which is usually the broadcast address on (one of) the -local network(s) or a multicast address assigned to NTP. -The IANA -has assigned the multicast group address IPv4 224.0.1.1 and -IPv6 ff05::101 (site local) exclusively to -NTP, but other nonconflicting addresses can be used to contain the -messages within administrative boundaries. -Ordinarily, this -specification applies only to the local server operating as a -sender; for operation as a broadcast client, see the -\f\*[B-Font]broadcastclient\f[] -or -\f\*[B-Font]multicastclient\f[] -commands -below. -.TP 7 -.NOP \f\*[B-Font]manycastclient\f[] -For type m addresses (only), this command mobilizes a -manycast client mode association for the multicast address -specified. -In this case a specific address must be supplied which -matches the address used on the -\f\*[B-Font]manycastserver\f[] -command for -the designated manycast servers. -The NTP multicast address -224.0.1.1 assigned by the IANA should NOT be used, unless specific -means are taken to avoid spraying large areas of the Internet with -these messages and causing a possibly massive implosion of replies -at the sender. -The -\f\*[B-Font]manycastserver\f[] -command specifies that the local server -is to operate in client mode with the remote servers that are -discovered as the result of broadcast/multicast messages. -The -client broadcasts a request message to the group address associated -with the specified -\f\*[I-Font]address\f[] -and specifically enabled -servers respond to these messages. -The client selects the servers -providing the best time and continues as with the -\f\*[B-Font]server\f[] -command. -The remaining servers are discarded as if never -heard. -.PP -.sp \n(Ppu -.ne 2 - -Options: -.TP 7 -.NOP \f\*[B-Font]autokey\f[] -All packets sent to and received from the server or peer are to -include authentication fields encrypted using the autokey scheme -described in -\fIAuthentication\f[] \fIOptions\f[]. -.TP 7 -.NOP \f\*[B-Font]burst\f[] -when the server is reachable, send a burst of eight packets -instead of the usual one. -The packet spacing is normally 2 s; -however, the spacing between the first and second packets -can be changed with the calldelay command to allow -additional time for a modem or ISDN call to complete. -This is designed to improve timekeeping quality -with the -\f\*[B-Font]server\f[] -command and s addresses. -.TP 7 -.NOP \f\*[B-Font]iburst\f[] -When the server is unreachable, send a burst of eight packets -instead of the usual one. -The packet spacing is normally 2 s; -however, the spacing between the first two packets can be -changed with the calldelay command to allow -additional time for a modem or ISDN call to complete. -This is designed to speed the initial synchronization -acquisition with the -\f\*[B-Font]server\f[] -command and s addresses and when -\fCntpd\fR(@NTPD_MS@)\f[] -is started with the -\f\*[B-Font]\-q\f[] -option. -.TP 7 -.NOP \f\*[B-Font]key\f[] \f\*[I-Font]key\f[] -All packets sent to and received from the server or peer are to -include authentication fields encrypted using the specified -\f\*[I-Font]key\f[] -identifier with values from 1 to 65534, inclusive. -The -default is to include no encryption field. -.TP 7 -.NOP \f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[] -.TP 7 -.NOP \f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[] -These options specify the minimum and maximum poll intervals -for NTP messages, as a power of 2 in seconds -The maximum poll -interval defaults to 10 (1,024 s), but can be increased by the -\f\*[B-Font]maxpoll\f[] -option to an upper limit of 17 (36.4 h). -The -minimum poll interval defaults to 6 (64 s), but can be decreased by -the -\f\*[B-Font]minpoll\f[] -option to a lower limit of 4 (16 s). -.TP 7 -.NOP \f\*[B-Font]noselect\f[] -Marks the server as unused, except for display purposes. -The server is discarded by the selection algroithm. -.TP 7 -.NOP \f\*[B-Font]prefer\f[] -Marks the server as preferred. -All other things being equal, -this host will be chosen for synchronization among a set of -correctly operating hosts. -See the -"Mitigation Rules and the prefer Keyword" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]) -for further information. -.TP 7 -.NOP \f\*[B-Font]ttl\f[] \f\*[I-Font]ttl\f[] -This option is used only with broadcast server and manycast -client modes. -It specifies the time-to-live -\f\*[I-Font]ttl\f[] -to -use on broadcast server and multicast server and the maximum -\f\*[I-Font]ttl\f[] -for the expanding ring search with manycast -client packets. -Selection of the proper value, which defaults to -127, is something of a black art and should be coordinated with the -network administrator. -.TP 7 -.NOP \f\*[B-Font]version\f[] \f\*[I-Font]version\f[] -Specifies the version number to be used for outgoing NTP -packets. -Versions 1-4 are the choices, with version 4 the -default. -.PP -.SS Auxiliary Commands -.TP 7 -.NOP \f\*[B-Font]broadcastclient\f[] -This command enables reception of broadcast server messages to -any local interface (type b) address. -Upon receiving a message for -the first time, the broadcast client measures the nominal server -propagation delay using a brief client/server exchange with the -server, then enters the broadcast client mode, in which it -synchronizes to succeeding broadcast messages. -Note that, in order -to avoid accidental or malicious disruption in this mode, both the -server and client should operate using symmetric-key or public-key -authentication as described in -\fIAuthentication\f[] \fIOptions\f[]. -.TP 7 -.NOP \f\*[B-Font]manycastserver\f[] \f\*[I-Font]address\f[] \f\*[I-Font]...\f[] -This command enables reception of manycast client messages to -the multicast group address(es) (type m) specified. -At least one -address is required, but the NTP multicast address 224.0.1.1 -assigned by the IANA should NOT be used, unless specific means are -taken to limit the span of the reply and avoid a possibly massive -implosion at the original sender. -Note that, in order to avoid -accidental or malicious disruption in this mode, both the server -and client should operate using symmetric-key or public-key -authentication as described in -\fIAuthentication\f[] \fIOptions\f[]. -.TP 7 -.NOP \f\*[B-Font]multicastclient\f[] \f\*[I-Font]address\f[] \f\*[I-Font]...\f[] -This command enables reception of multicast server messages to -the multicast group address(es) (type m) specified. -Upon receiving -a message for the first time, the multicast client measures the -nominal server propagation delay using a brief client/server -exchange with the server, then enters the broadcast client mode, in -which it synchronizes to succeeding multicast messages. -Note that, -in order to avoid accidental or malicious disruption in this mode, -both the server and client should operate using symmetric-key or -public-key authentication as described in -\fIAuthentication\f[] \fIOptions\f[]. -.PP -.SH Authentication Support -Authentication support allows the NTP client to verify that the -server is in fact known and trusted and not an intruder intending -accidentally or on purpose to masquerade as that server. -The NTPv3 -specification RFC-1305 defines a scheme which provides -cryptographic authentication of received NTP packets. -Originally, -this was done using the Data Encryption Standard (DES) algorithm -operating in Cipher Block Chaining (CBC) mode, commonly called -DES-CBC. -Subsequently, this was replaced by the RSA Message Digest -5 (MD5) algorithm using a private key, commonly called keyed-MD5. -Either algorithm computes a message digest, or one-way hash, which -can be used to verify the server has the correct private key and -key identifier. -.sp \n(Ppu -.ne 2 - -NTPv4 retains the NTPv3 scheme, properly described as symmetric key -cryptography and, in addition, provides a new Autokey scheme -based on public key cryptography. -Public key cryptography is generally considered more secure -than symmetric key cryptography, since the security is based -on a private value which is generated by each server and -never revealed. -With Autokey all key distribution and -management functions involve only public values, which -considerably simplifies key distribution and storage. -Public key management is based on X.509 certificates, -which can be provided by commercial services or -produced by utility programs in the OpenSSL software library -or the NTPv4 distribution. -.sp \n(Ppu -.ne 2 - -While the algorithms for symmetric key cryptography are -included in the NTPv4 distribution, public key cryptography -requires the OpenSSL software library to be installed -before building the NTP distribution. -Directions for doing that -are on the Building and Installing the Distribution page. -.sp \n(Ppu -.ne 2 - -Authentication is configured separately for each association -using the -\f\*[B-Font]key\f[] -or -\f\*[B-Font]autokey\f[] -subcommand on the -\f\*[B-Font]peer\f[], -\f\*[B-Font]server\f[], -\f\*[B-Font]broadcast\f[] -and -\f\*[B-Font]manycastclient\f[] -configuration commands as described in -\fIConfiguration\f[] \fIOptions\f[] -page. -The authentication -options described below specify the locations of the key files, -if other than default, which symmetric keys are trusted -and the interval between various operations, if other than default. -.sp \n(Ppu -.ne 2 - -Authentication is always enabled, -although ineffective if not configured as -described below. -If a NTP packet arrives -including a message authentication -code (MAC), it is accepted only if it -passes all cryptographic checks. -The -checks require correct key ID, key value -and message digest. -If the packet has -been modified in any way or replayed -by an intruder, it will fail one or more -of these checks and be discarded. -Furthermore, the Autokey scheme requires a -preliminary protocol exchange to obtain -the server certificate, verify its -credentials and initialize the protocol -.sp \n(Ppu -.ne 2 - -The -\f\*[B-Font]auth\f[] -flag controls whether new associations or -remote configuration commands require cryptographic authentication. -This flag can be set or reset by the -\f\*[B-Font]enable\f[] -and -\f\*[B-Font]disable\f[] -commands and also by remote -configuration commands sent by a -\fCntpdc\fR(@NTPDC_MS@)\f[] -program running in -another machine. -If this flag is enabled, which is the default -case, new broadcast client and symmetric passive associations and -remote configuration commands must be cryptographically -authenticated using either symmetric key or public key cryptography. -If this -flag is disabled, these operations are effective -even if not cryptographic -authenticated. -It should be understood -that operating with the -\f\*[B-Font]auth\f[] -flag disabled invites a significant vulnerability -where a rogue hacker can -masquerade as a falseticker and seriously -disrupt system timekeeping. -It is -important to note that this flag has no purpose -other than to allow or disallow -a new association in response to new broadcast -and symmetric active messages -and remote configuration commands and, in particular, -the flag has no effect on -the authentication process itself. -.sp \n(Ppu -.ne 2 - -An attractive alternative where multicast support is available -is manycast mode, in which clients periodically troll -for servers as described in the -\fIAutomatic\f[] \fINTP\f[] \fIConfiguration\f[] \fIOptions\f[] -page. -Either symmetric key or public key -cryptographic authentication can be used in this mode. -The principle advantage -of manycast mode is that potential servers need not be -configured in advance, -since the client finds them during regular operation, -and the configuration -files for all clients can be identical. -.sp \n(Ppu -.ne 2 - -The security model and protocol schemes for -both symmetric key and public key -cryptography are summarized below; -further details are in the briefings, papers -and reports at the NTP project page linked from -\f[C]http://www.ntp.org/\f[]. -.SS Symmetric-Key Cryptography -The original RFC-1305 specification allows any one of possibly -65,534 keys, each distinguished by a 32-bit key identifier, to -authenticate an association. -The servers and clients involved must -agree on the key and key identifier to -authenticate NTP packets. -Keys and -related information are specified in a key -file, usually called -\fIntp.keys\f[], -which must be distributed and stored using -secure means beyond the scope of the NTP protocol itself. -Besides the keys used -for ordinary NTP associations, -additional keys can be used as passwords for the -\fCntpq\fR(@NTPQ_MS@)\f[] -and -\fCntpdc\fR(@NTPDC_MS@)\f[] -utility programs. -.sp \n(Ppu -.ne 2 - -When -\fCntpd\fR(@NTPD_MS@)\f[] -is first started, it reads the key file specified in the -\f\*[B-Font]keys\f[] -configuration command and installs the keys -in the key cache. -However, -individual keys must be activated with the -\f\*[B-Font]trusted\f[] -command before use. -This -allows, for instance, the installation of possibly -several batches of keys and -then activating or deactivating each batch -remotely using -\fCntpdc\fR(@NTPDC_MS@)\f[]. -This also provides a revocation capability that can be used -if a key becomes compromised. -The -\f\*[B-Font]requestkey\f[] -command selects the key used as the password for the -\fCntpdc\fR(@NTPDC_MS@)\f[] -utility, while the -\f\*[B-Font]controlkey\f[] -command selects the key used as the password for the -\fCntpq\fR(@NTPQ_MS@)\f[] -utility. -.SS Public Key Cryptography -NTPv4 supports the original NTPv3 symmetric key scheme -described in RFC-1305 and in addition the Autokey protocol, -which is based on public key cryptography. -The Autokey Version 2 protocol described on the Autokey Protocol -page verifies packet integrity using MD5 message digests -and verifies the source with digital signatures and any of several -digest/signature schemes. -Optional identity schemes described on the Identity Schemes -page and based on cryptographic challenge/response algorithms -are also available. -Using all of these schemes provides strong security against -replay with or without modification, spoofing, masquerade -and most forms of clogging attacks. -.\" .Pp -.\" The cryptographic means necessary for all Autokey operations -.\" is provided by the OpenSSL software library. -.\" This library is available from http://www.openssl.org/ -.\" and can be installed using the procedures outlined -.\" in the Building and Installing the Distribution page. -.\" Once installed, -.\" the configure and build -.\" process automatically detects the library and links -.\" the library routines required. -.sp \n(Ppu -.ne 2 - -The Autokey protocol has several modes of operation -corresponding to the various NTP modes supported. -Most modes use a special cookie which can be -computed independently by the client and server, -but encrypted in transmission. -All modes use in addition a variant of the S-KEY scheme, -in which a pseudo-random key list is generated and used -in reverse order. -These schemes are described along with an executive summary, -current status, briefing slides and reading list on the -\fIAutonomous\f[] \fIAuthentication\f[] -page. -.sp \n(Ppu -.ne 2 - -The specific cryptographic environment used by Autokey servers -and clients is determined by a set of files -and soft links generated by the -\fCntp-keygen\fR(1ntpkeygenmdoc)\f[] -program. -This includes a required host key file, -required certificate file and optional sign key file, -leapsecond file and identity scheme files. -The -digest/signature scheme is specified in the X.509 certificate -along with the matching sign key. -There are several schemes -available in the OpenSSL software library, each identified -by a specific string such as -\f\*[B-Font]md5WithRSAEncryption\f[], -which stands for the MD5 message digest with RSA -encryption scheme. -The current NTP distribution supports -all the schemes in the OpenSSL library, including -those based on RSA and DSA digital signatures. -.sp \n(Ppu -.ne 2 - -NTP secure groups can be used to define cryptographic compartments -and security hierarchies. -It is important that every host -in the group be able to construct a certificate trail to one -or more trusted hosts in the same group. -Each group -host runs the Autokey protocol to obtain the certificates -for all hosts along the trail to one or more trusted hosts. -This requires the configuration file in all hosts to be -engineered so that, even under anticipated failure conditions, -the NTP subnet will form such that every group host can find -a trail to at least one trusted host. -.SS Naming and Addressing -It is important to note that Autokey does not use DNS to -resolve addresses, since DNS can't be completely trusted -until the name servers have synchronized clocks. -The cryptographic name used by Autokey to bind the host identity -credentials and cryptographic values must be independent -of interface, network and any other naming convention. -The name appears in the host certificate in either or both -the subject and issuer fields, so protection against -DNS compromise is essential. -.sp \n(Ppu -.ne 2 - -By convention, the name of an Autokey host is the name returned -by the Unix -\fCgethostname\fR(2)\f[] -system call or equivalent in other systems. -By the system design -model, there are no provisions to allow alternate names or aliases. -However, this is not to say that DNS aliases, different names -for each interface, etc., are constrained in any way. -.sp \n(Ppu -.ne 2 - -It is also important to note that Autokey verifies authenticity -using the host name, network address and public keys, -all of which are bound together by the protocol specifically -to deflect masquerade attacks. -For this reason Autokey -includes the source and destinatino IP addresses in message digest -computations and so the same addresses must be available -at both the server and client. -For this reason operation -with network address translation schemes is not possible. -This reflects the intended robust security model where government -and corporate NTP servers are operated outside firewall perimeters. -.SS Operation -A specific combination of authentication scheme (none, -symmetric key, public key) and identity scheme is called -a cryptotype, although not all combinations are compatible. -There may be management configurations where the clients, -servers and peers may not all support the same cryptotypes. -A secure NTPv4 subnet can be configured in many ways while -keeping in mind the principles explained above and -in this section. -Note however that some cryptotype -combinations may successfully interoperate with each other, -but may not represent good security practice. -.sp \n(Ppu -.ne 2 - -The cryptotype of an association is determined at the time -of mobilization, either at configuration time or some time -later when a message of appropriate cryptotype arrives. -When mobilized by a -\f\*[B-Font]server\f[] -or -\f\*[B-Font]peer\f[] -configuration command and no -\f\*[B-Font]key\f[] -or -\f\*[B-Font]autokey\f[] -subcommands are present, the association is not -authenticated; if the -\f\*[B-Font]key\f[] -subcommand is present, the association is authenticated -using the symmetric key ID specified; if the -\f\*[B-Font]autokey\f[] -subcommand is present, the association is authenticated -using Autokey. -.sp \n(Ppu -.ne 2 - -When multiple identity schemes are supported in the Autokey -protocol, the first message exchange determines which one is used. -The client request message contains bits corresponding -to which schemes it has available. -The server response message -contains bits corresponding to which schemes it has available. -Both server and client match the received bits with their own -and select a common scheme. -.sp \n(Ppu -.ne 2 - -Following the principle that time is a public value, -a server responds to any client packet that matches -its cryptotype capabilities. -Thus, a server receiving -an unauthenticated packet will respond with an unauthenticated -packet, while the same server receiving a packet of a cryptotype -it supports will respond with packets of that cryptotype. -However, unconfigured broadcast or manycast client -associations or symmetric passive associations will not be -mobilized unless the server supports a cryptotype compatible -with the first packet received. -By default, unauthenticated associations will not be mobilized -unless overridden in a decidedly dangerous way. -.sp \n(Ppu -.ne 2 - -Some examples may help to reduce confusion. -Client Alice has no specific cryptotype selected. -Server Bob has both a symmetric key file and minimal Autokey files. -Alice's unauthenticated messages arrive at Bob, who replies with -unauthenticated messages. -Cathy has a copy of Bob's symmetric -key file and has selected key ID 4 in messages to Bob. -Bob verifies the message with his key ID 4. -If it's the -same key and the message is verified, Bob sends Cathy a reply -authenticated with that key. -If verification fails, -Bob sends Cathy a thing called a crypto-NAK, which tells her -something broke. -She can see the evidence using the -\fCntpq\fR(@NTPQ_MS@)\f[] -program. -.sp \n(Ppu -.ne 2 - -Denise has rolled her own host key and certificate. -She also uses one of the identity schemes as Bob. -She sends the first Autokey message to Bob and they -both dance the protocol authentication and identity steps. -If all comes out okay, Denise and Bob continue as described above. -.sp \n(Ppu -.ne 2 - -It should be clear from the above that Bob can support -all the girls at the same time, as long as he has compatible -authentication and identity credentials. -Now, Bob can act just like the girls in his own choice of servers; -he can run multiple configured associations with multiple different -servers (or the same server, although that might not be useful). -But, wise security policy might preclude some cryptotype -combinations; for instance, running an identity scheme -with one server and no authentication with another might not be wise. -.SS Key Management -The cryptographic values used by the Autokey protocol are -incorporated as a set of files generated by the -\fCntp-keygen\fR(1ntpkeygenmdoc)\f[] -utility program, including symmetric key, host key and -public certificate files, as well as sign key, identity parameters -and leapseconds files. -Alternatively, host and sign keys and -certificate files can be generated by the OpenSSL utilities -and certificates can be imported from public certificate -authorities. -Note that symmetric keys are necessary for the -\fCntpq\fR(@NTPQ_MS@)\f[] -and -\fCntpdc\fR(@NTPDC_MS@)\f[] -utility programs. -The remaining files are necessary only for the -Autokey protocol. -.sp \n(Ppu -.ne 2 - -Certificates imported from OpenSSL or public certificate -authorities have certian limitations. -The certificate should be in ASN.1 syntax, X.509 Version 3 -format and encoded in PEM, which is the same format -used by OpenSSL. -The overall length of the certificate encoded -in ASN.1 must not exceed 1024 bytes. -The subject distinguished -name field (CN) is the fully qualified name of the host -on which it is used; the remaining subject fields are ignored. -The certificate extension fields must not contain either -a subject key identifier or a issuer key identifier field; -however, an extended key usage field for a trusted host must -contain the value -\f\*[B-Font]trustRoot\f[];. -Other extension fields are ignored. -.SS Authentication Commands -.TP 7 -.NOP \f\*[B-Font]autokey\f[] [\f\*[I-Font]logsec\f[]] -Specifies the interval between regenerations of the session key -list used with the Autokey protocol. -Note that the size of the key -list for each association depends on this interval and the current -poll interval. -The default value is 12 (4096 s or about 1.1 hours). -For poll intervals above the specified interval, a session key list -with a single entry will be regenerated for every message -sent. -.TP 7 -.NOP \f\*[B-Font]controlkey\f[] \f\*[I-Font]key\f[] -Specifies the key identifier to use with the -\fCntpq\fR(@NTPQ_MS@)\f[] -utility, which uses the standard -protocol defined in RFC-1305. -The -\f\*[I-Font]key\f[] -argument is -the key identifier for a trusted key, where the value can be in the -range 1 to 65,534, inclusive. -.TP 7 -.NOP \f\*[B-Font]crypto\f[] [\f\*[B-Font]cert\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]leap\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]randfile\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]host\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]sign\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]gq\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]gqpar\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]iffpar\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]mvpar\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]pw\f[] \f\*[I-Font]password\f[]] -This command requires the OpenSSL library. -It activates public key -cryptography, selects the message digest and signature -encryption scheme and loads the required private and public -values described above. -If one or more files are left unspecified, -the default names are used as described above. -Unless the complete path and name of the file are specified, the -location of a file is relative to the keys directory specified -in the -\f\*[B-Font]keysdir\f[] -command or default -\fI/usr/local/etc\f[]. -Following are the subcommands: -.RS -.TP 7 -.NOP \f\*[B-Font]cert\f[] \f\*[I-Font]file\f[] -Specifies the location of the required host public certificate file. -This overrides the link -\fIntpkey_cert_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]gqpar\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional GQ parameters file. -This -overrides the link -\fIntpkey_gq_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]host\f[] \f\*[I-Font]file\f[] -Specifies the location of the required host key file. -This overrides -the link -\fIntpkey_key_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]iffpar\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional IFF parameters file.This -overrides the link -\fIntpkey_iff_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]leap\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional leapsecond file. -This overrides the link -\fIntpkey_leap\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]mvpar\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional MV parameters file. -This -overrides the link -\fIntpkey_mv_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -.TP 7 -.NOP \f\*[B-Font]pw\f[] \f\*[I-Font]password\f[] -Specifies the password to decrypt files containing private keys and -identity parameters. -This is required only if these files have been -encrypted. -.TP 7 -.NOP \f\*[B-Font]randfile\f[] \f\*[I-Font]file\f[] -Specifies the location of the random seed file used by the OpenSSL -library. -The defaults are described in the main text above. -.TP 7 -.NOP \f\*[B-Font]sign\f[] \f\*[I-Font]file\f[] -Specifies the location of the optional sign key file. -This overrides -the link -\fIntpkey_sign_\f[]\f\*[I-Font]hostname\f[] -in the keys directory. -If this file is -not found, the host key is also the sign key. -.RE -.TP 7 -.NOP \f\*[B-Font]keys\f[] \f\*[I-Font]keyfile\f[] -Specifies the complete path and location of the MD5 key file -containing the keys and key identifiers used by -\fCntpd\fR(@NTPD_MS@)\f[], -\fCntpq\fR(@NTPQ_MS@)\f[] -and -\fCntpdc\fR(@NTPDC_MS@)\f[] -when operating with symmetric key cryptography. -This is the same operation as the -\f\*[B-Font]\-k\f[] -command line option. -.TP 7 -.NOP \f\*[B-Font]keysdir\f[] \f\*[I-Font]path\f[] -This command specifies the default directory path for -cryptographic keys, parameters and certificates. -The default is -\fI/usr/local/etc/\f[]. -.TP 7 -.NOP \f\*[B-Font]requestkey\f[] \f\*[I-Font]key\f[] -Specifies the key identifier to use with the -\fCntpdc\fR(@NTPDC_MS@)\f[] -utility program, which uses a -proprietary protocol specific to this implementation of -\fCntpd\fR(@NTPD_MS@)\f[]. -The -\f\*[I-Font]key\f[] -argument is a key identifier -for the trusted key, where the value can be in the range 1 to -65,534, inclusive. -.TP 7 -.NOP \f\*[B-Font]revoke\f[] \f\*[I-Font]logsec\f[] -Specifies the interval between re-randomization of certain -cryptographic values used by the Autokey scheme, as a power of 2 in -seconds. -These values need to be updated frequently in order to -deflect brute-force attacks on the algorithms of the scheme; -however, updating some values is a relatively expensive operation. -The default interval is 16 (65,536 s or about 18 hours). -For poll -intervals above the specified interval, the values will be updated -for every message sent. -.TP 7 -.NOP \f\*[B-Font]trustedkey\f[] \f\*[I-Font]key\f[] \f\*[I-Font]...\f[] -Specifies the key identifiers which are trusted for the -purposes of authenticating peers with symmetric key cryptography, -as well as keys used by the -\fCntpq\fR(@NTPQ_MS@)\f[] -and -\fCntpdc\fR(@NTPDC_MS@)\f[] -programs. -The authentication procedures require that both the local -and remote servers share the same key and key identifier for this -purpose, although different keys can be used with different -servers. -The -\f\*[I-Font]key\f[] -arguments are 32-bit unsigned -integers with values from 1 to 65,534. -.PP -.SS Error Codes -The following error codes are reported via the NTP control -and monitoring protocol trap mechanism. -.TP 7 -.NOP 101 -(bad field format or length) -The packet has invalid version, length or format. -.TP 7 -.NOP 102 -(bad timestamp) -The packet timestamp is the same or older than the most recent received. -This could be due to a replay or a server clock time step. -.TP 7 -.NOP 103 -(bad filestamp) -The packet filestamp is the same or older than the most recent received. -This could be due to a replay or a key file generation error. -.TP 7 -.NOP 104 -(bad or missing public key) -The public key is missing, has incorrect format or is an unsupported type. -.TP 7 -.NOP 105 -(unsupported digest type) -The server requires an unsupported digest/signature scheme. -.TP 7 -.NOP 106 -(mismatched digest types) -Not used. -.TP 7 -.NOP 107 -(bad signature length) -The signature length does not match the current public key. -.TP 7 -.NOP 108 -(signature not verified) -The message fails the signature check. -It could be bogus or signed by a -different private key. -.TP 7 -.NOP 109 -(certificate not verified) -The certificate is invalid or signed with the wrong key. -.TP 7 -.NOP 110 -(certificate not verified) -The certificate is not yet valid or has expired or the signature could not -be verified. -.TP 7 -.NOP 111 -(bad or missing cookie) -The cookie is missing, corrupted or bogus. -.TP 7 -.NOP 112 -(bad or missing leapseconds table) -The leapseconds table is missing, corrupted or bogus. -.TP 7 -.NOP 113 -(bad or missing certificate) -The certificate is missing, corrupted or bogus. -.TP 7 -.NOP 114 -(bad or missing identity) -The identity key is missing, corrupt or bogus. -.PP -.SH Monitoring Support -\fCntpd\fR(@NTPD_MS@)\f[] -includes a comprehensive monitoring facility suitable -for continuous, long term recording of server and client -timekeeping performance. -See the -\f\*[B-Font]statistics\f[] -command below -for a listing and example of each type of statistics currently -supported. -Statistic files are managed using file generation sets -and scripts in the -\fI./scripts\f[] -directory of this distribution. -Using -these facilities and -UNIX -\fCcron\fR(8)\f[] -jobs, the data can be -automatically summarized and archived for retrospective analysis. -.SS Monitoring Commands -.TP 7 -.NOP \f\*[B-Font]statistics\f[] \f\*[I-Font]name\f[] \f\*[I-Font]...\f[] -Enables writing of statistics records. -Currently, eight kinds of -\f\*[I-Font]name\f[] -statistics are supported. -.RS -.TP 7 -.NOP \f\*[B-Font]clockstats\f[] -Enables recording of clock driver statistics information. -Each update -received from a clock driver appends a line of the following form to -the file generation set named -\f\*[B-Font]clockstats\f[]: -.br -.in +4 -.nf -49213 525.624 127.127.4.1 93 226 00:08:29.606 D -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and time -(seconds and fraction past UTC midnight). -The next field shows the -clock address in dotted-quad notation. -The final field shows the last -timecode received from the clock in decoded ASCII format, where -meaningful. -In some clock drivers a good deal of additional information -can be gathered and displayed as well. -See information specific to each -clock for further details. -.TP 7 -.NOP \f\*[B-Font]cryptostats\f[] -This option requires the OpenSSL cryptographic software library. -It -enables recording of cryptographic public key protocol information. -Each message received by the protocol module appends a line of the -following form to the file generation set named -\f\*[B-Font]cryptostats\f[]: -.br -.in +4 -.nf -49213 525.624 127.127.4.1 message -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and time -(seconds and fraction past UTC midnight). -The next field shows the peer -address in dotted-quad notation, The final message field includes the -message type and certain ancillary information. -See the -\fIAuthentication\f[] \fIOptions\f[] -section for further information. -.TP 7 -.NOP \f\*[B-Font]loopstats\f[] -Enables recording of loop filter statistics information. -Each -update of the local clock outputs a line of the following form to -the file generation set named -\f\*[B-Font]loopstats\f[]: -.br -.in +4 -.nf -50935 75440.031 0.000006019 13.778190 0.000351733 0.0133806 -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and -time (seconds and fraction past UTC midnight). -The next five fields -show time offset (seconds), frequency offset (parts per million \- -PPM), RMS jitter (seconds), Allan deviation (PPM) and clock -discipline time constant. -.TP 7 -.NOP \f\*[B-Font]peerstats\f[] -Enables recording of peer statistics information. -This includes -statistics records of all peers of a NTP server and of special -signals, where present and configured. -Each valid update appends a -line of the following form to the current element of a file -generation set named -\f\*[B-Font]peerstats\f[]: -.br -.in +4 -.nf -48773 10847.650 127.127.4.1 9714 \-0.001605376 0.000000000 0.001424877 0.000958674 -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and -time (seconds and fraction past UTC midnight). -The next two fields -show the peer address in dotted-quad notation and status, -respectively. -The status field is encoded in hex in the format -described in Appendix A of the NTP specification RFC 1305. -The final four fields show the offset, -delay, dispersion and RMS jitter, all in seconds. -.TP 7 -.NOP \f\*[B-Font]rawstats\f[] -Enables recording of raw-timestamp statistics information. -This -includes statistics records of all peers of a NTP server and of -special signals, where present and configured. -Each NTP message -received from a peer or clock driver appends a line of the -following form to the file generation set named -\f\*[B-Font]rawstats\f[]: -.br -.in +4 -.nf -50928 2132.543 128.4.1.1 128.4.1.20 3102453281.584327000 3102453281.58622800031 02453332.540806000 3102453332.541458000 -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and -time (seconds and fraction past UTC midnight). -The next two fields -show the remote peer or clock address followed by the local address -in dotted-quad notation. -The final four fields show the originate, -receive, transmit and final NTP timestamps in order. -The timestamp -values are as received and before processing by the various data -smoothing and mitigation algorithms. -.TP 7 -.NOP \f\*[B-Font]sysstats\f[] -Enables recording of ntpd statistics counters on a periodic basis. -Each -hour a line of the following form is appended to the file generation -set named -\f\*[B-Font]sysstats\f[]: -.br -.in +4 -.nf -50928 2132.543 36000 81965 0 9546 56 71793 512 540 10 147 -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -The first two fields show the date (Modified Julian Day) and time -(seconds and fraction past UTC midnight). -The remaining ten fields show -the statistics counter values accumulated since the last generated -line. -.RS -.TP 7 -.NOP Time since restart \f\*[B-Font]36000\f[] -Time in hours since the system was last rebooted. -.TP 7 -.NOP Packets received \f\*[B-Font]81965\f[] -Total number of packets received. -.TP 7 -.NOP Packets processed \f\*[B-Font]0\f[] -Number of packets received in response to previous packets sent -.TP 7 -.NOP Current version \f\*[B-Font]9546\f[] -Number of packets matching the current NTP version. -.TP 7 -.NOP Previous version \f\*[B-Font]56\f[] -Number of packets matching the previous NTP version. -.TP 7 -.NOP Bad version \f\*[B-Font]71793\f[] -Number of packets matching neither NTP version. -.TP 7 -.NOP Access denied \f\*[B-Font]512\f[] -Number of packets denied access for any reason. -.TP 7 -.NOP Bad length or format \f\*[B-Font]540\f[] -Number of packets with invalid length, format or port number. -.TP 7 -.NOP Bad authentication \f\*[B-Font]10\f[] -Number of packets not verified as authentic. -.TP 7 -.NOP Rate exceeded \f\*[B-Font]147\f[] -Number of packets discarded due to rate limitation. -.RE -.TP 7 -.NOP \f\*[B-Font]statsdir\f[] \f\*[I-Font]directory_path\f[] -Indicates the full path of a directory where statistics files -should be created (see below). -This keyword allows -the (otherwise constant) -\f\*[B-Font]filegen\f[] -filename prefix to be modified for file generation sets, which -is useful for handling statistics logs. -.TP 7 -.NOP \f\*[B-Font]filegen\f[] \f\*[I-Font]name\f[] [\f\*[B-Font]file\f[] \f\*[I-Font]filename\f[]] [\f\*[B-Font]type\f[] \f\*[I-Font]typename\f[]] [\f\*[B-Font]link\f[] | \f\*[B-Font]nolink\f[]] [\f\*[B-Font]enable\f[] | \f\*[B-Font]disable\f[]] -Configures setting of generation file set name. -Generation -file sets provide a means for handling files that are -continuously growing during the lifetime of a server. -Server statistics are a typical example for such files. -Generation file sets provide access to a set of files used -to store the actual data. -At any time at most one element -of the set is being written to. -The type given specifies -when and how data will be directed to a new element of the set. -This way, information stored in elements of a file set -that are currently unused are available for administrational -operations without the risk of disturbing the operation of ntpd. -(Most important: they can be removed to free space for new data -produced.) -.sp \n(Ppu -.ne 2 - -Note that this command can be sent from the -\fCntpdc\fR(@NTPDC_MS@)\f[] -program running at a remote location. -.RS -.TP 7 -.NOP \f\*[B-Font]name\f[] -This is the type of the statistics records, as shown in the -\f\*[B-Font]statistics\f[] -command. -.TP 7 -.NOP \f\*[B-Font]file\f[] \f\*[I-Font]filename\f[] -This is the file name for the statistics records. -Filenames of set -members are built from three concatenated elements -\f\*[B-Font]prefix\f[], -\f\*[B-Font]filename\f[] -and -\f\*[B-Font]suffix\f[]: -.RS -.TP 7 -.NOP \f\*[B-Font]prefix\f[] -This is a constant filename path. -It is not subject to -modifications via the -\f\*[I-Font]filegen\f[] -option. -It is defined by the -server, usually specified as a compile-time constant. -It may, -however, be configurable for individual file generation sets -via other commands. -For example, the prefix used with -\f\*[I-Font]loopstats\f[] -and -\f\*[I-Font]peerstats\f[] -generation can be configured using the -\f\*[I-Font]statsdir\f[] -option explained above. -.TP 7 -.NOP \f\*[B-Font]filename\f[] -This string is directly concatenated to the prefix mentioned -above (no intervening -\[oq]/\[cq]). -This can be modified using -the file argument to the -\f\*[I-Font]filegen\f[] -statement. -No -\fI..\f[] -elements are -allowed in this component to prevent filenames referring to -parts outside the filesystem hierarchy denoted by -\f\*[I-Font]prefix\f[]. -.TP 7 -.NOP \f\*[B-Font]suffix\f[] -This part is reflects individual elements of a file set. -It is -generated according to the type of a file set. -.RE -.TP 7 -.NOP \f\*[B-Font]type\f[] \f\*[I-Font]typename\f[] -A file generation set is characterized by its type. -The following -types are supported: -.RS -.TP 7 -.NOP \f\*[B-Font]none\f[] -The file set is actually a single plain file. -.TP 7 -.NOP \f\*[B-Font]pid\f[] -One element of file set is used per incarnation of a ntpd -server. -This type does not perform any changes to file set -members during runtime, however it provides an easy way of -separating files belonging to different -\fCntpd\fR(@NTPD_MS@)\f[] -server incarnations. -The set member filename is built by appending a -\[oq]\&.\[cq] -to concatenated -\f\*[I-Font]prefix\f[] -and -\f\*[I-Font]filename\f[] -strings, and -appending the decimal representation of the process ID of the -\fCntpd\fR(@NTPD_MS@)\f[] -server process. -.TP 7 -.NOP \f\*[B-Font]day\f[] -One file generation set element is created per day. -A day is -defined as the period between 00:00 and 24:00 UTC. -The file set -member suffix consists of a -\[oq]\&.\[cq] -and a day specification in -the form -\f\*[B-Font]YYYYMMdd\f[]. -\f\*[B-Font]YYYY\f[] -is a 4-digit year number (e.g., 1992). -\f\*[B-Font]MM\f[] -is a two digit month number. -\f\*[B-Font]dd\f[] -is a two digit day number. -Thus, all information written at 10 December 1992 would end up -in a file named -\f\*[I-Font]prefix\f[] -\f\*[I-Font]filename\f[].19921210. -.TP 7 -.NOP \f\*[B-Font]week\f[] -Any file set member contains data related to a certain week of -a year. -The term week is defined by computing day-of-year -modulo 7. -Elements of such a file generation set are -distinguished by appending the following suffix to the file set -filename base: A dot, a 4-digit year number, the letter -\f\*[B-Font]W\f[], -and a 2-digit week number. -For example, information from January, -10th 1992 would end up in a file with suffix -.NOP. \f\*[I-Font]1992W1\f[]. -.TP 7 -.NOP \f\*[B-Font]month\f[] -One generation file set element is generated per month. -The -file name suffix consists of a dot, a 4-digit year number, and -a 2-digit month. -.TP 7 -.NOP \f\*[B-Font]year\f[] -One generation file element is generated per year. -The filename -suffix consists of a dot and a 4 digit year number. -.TP 7 -.NOP \f\*[B-Font]age\f[] -This type of file generation sets changes to a new element of -the file set every 24 hours of server operation. -The filename -suffix consists of a dot, the letter -\f\*[B-Font]a\f[], -and an 8-digit number. -This number is taken to be the number of seconds the server is -running at the start of the corresponding 24-hour period. -Information is only written to a file generation by specifying -\f\*[B-Font]enable\f[]; -output is prevented by specifying -\f\*[B-Font]disable\f[]. -.RE -.TP 7 -.NOP \f\*[B-Font]link\f[] | \f\*[B-Font]nolink\f[] -It is convenient to be able to access the current element of a file -generation set by a fixed name. -This feature is enabled by -specifying -\f\*[B-Font]link\f[] -and disabled using -\f\*[B-Font]nolink\f[]. -If link is specified, a -hard link from the current file set element to a file without -suffix is created. -When there is already a file with this name and -the number of links of this file is one, it is renamed appending a -dot, the letter -\f\*[B-Font]C\f[], -and the pid of the ntpd server process. -When the -number of links is greater than one, the file is unlinked. -This -allows the current file to be accessed by a constant name. -.TP 7 -.NOP \f\*[B-Font]enable\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]disable\f[] -Enables or disables the recording function. -.RE -.RE -.PP -.SH Access Control Support -The -\fCntpd\fR(@NTPD_MS@)\f[] -daemon implements a general purpose address/mask based restriction -list. -The list contains address/match entries sorted first -by increasing address values and and then by increasing mask values. -A match occurs when the bitwise AND of the mask and the packet -source address is equal to the bitwise AND of the mask and -address in the list. -The list is searched in order with the -last match found defining the restriction flags associated -with the entry. -Additional information and examples can be found in the -"Notes on Configuring NTP and Setting up a NTP Subnet" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.sp \n(Ppu -.ne 2 - -The restriction facility was implemented in conformance -with the access policies for the original NSFnet backbone -time servers. -Later the facility was expanded to deflect -cryptographic and clogging attacks. -While this facility may -be useful for keeping unwanted or broken or malicious clients -from congesting innocent servers, it should not be considered -an alternative to the NTP authentication facilities. -Source address based restrictions are easily circumvented -by a determined cracker. -.sp \n(Ppu -.ne 2 - -Clients can be denied service because they are explicitly -included in the restrict list created by the restrict command -or implicitly as the result of cryptographic or rate limit -violations. -Cryptographic violations include certificate -or identity verification failure; rate limit violations generally -result from defective NTP implementations that send packets -at abusive rates. -Some violations cause denied service -only for the offending packet, others cause denied service -for a timed period and others cause the denied service for -an indefinate period. -When a client or network is denied access -for an indefinate period, the only way at present to remove -the restrictions is by restarting the server. -.SS The Kiss-of-Death Packet -Ordinarily, packets denied service are simply dropped with no -further action except incrementing statistics counters. -Sometimes a -more proactive response is needed, such as a server message that -explicitly requests the client to stop sending and leave a message -for the system operator. -A special packet format has been created -for this purpose called the "kiss-of-death" (KoD) packet. -KoD packets have the leap bits set unsynchronized and stratum set -to zero and the reference identifier field set to a four-byte -ASCII code. -If the -\f\*[B-Font]noserve\f[] -or -\f\*[B-Font]notrust\f[] -flag of the matching restrict list entry is set, -the code is "DENY"; if the -\f\*[B-Font]limited\f[] -flag is set and the rate limit -is exceeded, the code is "RATE". -Finally, if a cryptographic violation occurs, the code is "CRYP". -.sp \n(Ppu -.ne 2 - -A client receiving a KoD performs a set of sanity checks to -minimize security exposure, then updates the stratum and -reference identifier peer variables, sets the access -denied (TEST4) bit in the peer flash variable and sends -a message to the log. -As long as the TEST4 bit is set, -the client will send no further packets to the server. -The only way at present to recover from this condition is -to restart the protocol at both the client and server. -This -happens automatically at the client when the association times out. -It will happen at the server only if the server operator cooperates. -.SS Access Control Commands -.TP 7 -.NOP \f\*[B-Font]discard\f[] [\f\*[B-Font]average\f[] \f\*[I-Font]avg\f[]] [\f\*[B-Font]minimum\f[] \f\*[I-Font]min\f[]] [\f\*[B-Font]monitor\f[] \f\*[I-Font]prob\f[]] -Set the parameters of the -\f\*[B-Font]limited\f[] -facility which protects the server from -client abuse. -The -\f\*[B-Font]average\f[] -subcommand specifies the minimum average packet -spacing, while the -\f\*[B-Font]minimum\f[] -subcommand specifies the minimum packet spacing. -Packets that violate these minima are discarded -and a kiss-o'-death packet returned if enabled. -The default -minimum average and minimum are 5 and 2, respectively. -The monitor subcommand specifies the probability of discard -for packets that overflow the rate-control window. -.TP 7 -.NOP \f\*[B-Font]restrict\f[] \f\*[B-Font]address\f[] [\f\*[B-Font]mask\f[] \f\*[I-Font]mask\f[]] [\f\*[I-Font]flag\f[] \f\*[I-Font]...\f[]] -The -\f\*[I-Font]address\f[] -argument expressed in -dotted-quad form is the address of a host or network. -Alternatively, the -\f\*[I-Font]address\f[] -argument can be a valid host DNS name. -The -\f\*[I-Font]mask\f[] -argument expressed in dotted-quad form defaults to -\f\*[B-Font]255.255.255.255\f[], -meaning that the -\f\*[I-Font]address\f[] -is treated as the address of an individual host. -A default entry (address -\f\*[B-Font]0.0.0.0\f[], -mask -\f\*[B-Font]0.0.0.0\f[]) -is always included and is always the first entry in the list. -Note that text string -\f\*[B-Font]default\f[], -with no mask option, may -be used to indicate the default entry. -In the current implementation, -\f\*[B-Font]flag\f[] -always -restricts access, i.e., an entry with no flags indicates that free -access to the server is to be given. -The flags are not orthogonal, -in that more restrictive flags will often make less restrictive -ones redundant. -The flags can generally be classed into two -categories, those which restrict time service and those which -restrict informational queries and attempts to do run-time -reconfiguration of the server. -One or more of the following flags -may be specified: -.RS -.TP 7 -.NOP \f\*[B-Font]ignore\f[] -Deny packets of all kinds, including -\fCntpq\fR(@NTPQ_MS@)\f[] -and -\fCntpdc\fR(@NTPDC_MS@)\f[] -queries. -.TP 7 -.NOP \f\*[B-Font]kod\f[] -If this flag is set when an access violation occurs, a kiss-o'-death -(KoD) packet is sent. -KoD packets are rate limited to no more than one -per second. -If another KoD packet occurs within one second after the -last one, the packet is dropped. -.TP 7 -.NOP \f\*[B-Font]limited\f[] -Deny service if the packet spacing violates the lower limits specified -in the discard command. -A history of clients is kept using the -monitoring capability of -\fCntpd\fR(@NTPD_MS@)\f[]. -Thus, monitoring is always active as -long as there is a restriction entry with the -\f\*[B-Font]limited\f[] -flag. -.TP 7 -.NOP \f\*[B-Font]lowpriotrap\f[] -Declare traps set by matching hosts to be low priority. -The -number of traps a server can maintain is limited (the current limit -is 3). -Traps are usually assigned on a first come, first served -basis, with later trap requestors being denied service. -This flag -modifies the assignment algorithm by allowing low priority traps to -be overridden by later requests for normal priority traps. -.TP 7 -.NOP \f\*[B-Font]nomodify\f[] -Deny -\fCntpq\fR(@NTPQ_MS@)\f[] -and -\fCntpdc\fR(@NTPDC_MS@)\f[] -queries which attempt to modify the state of the -server (i.e., run time reconfiguration). -Queries which return -information are permitted. -.TP 7 -.NOP \f\*[B-Font]noquery\f[] -Deny -\fCntpq\fR(@NTPQ_MS@)\f[] -and -\fCntpdc\fR(@NTPDC_MS@)\f[] -queries. -Time service is not affected. -.TP 7 -.NOP \f\*[B-Font]nopeer\f[] -Deny packets which would result in mobilizing a new association. -This -includes broadcast and symmetric active packets when a configured -association does not exist. -.TP 7 -.NOP \f\*[B-Font]noserve\f[] -Deny all packets except -\fCntpq\fR(@NTPQ_MS@)\f[] -and -\fCntpdc\fR(@NTPDC_MS@)\f[] -queries. -.TP 7 -.NOP \f\*[B-Font]notrap\f[] -Decline to provide mode 6 control message trap service to matching -hosts. -The trap service is a subsystem of the ntpdq control message -protocol which is intended for use by remote event logging programs. -.TP 7 -.NOP \f\*[B-Font]notrust\f[] -Deny service unless the packet is cryptographically authenticated. -.TP 7 -.NOP \f\*[B-Font]ntpport\f[] -This is actually a match algorithm modifier, rather than a -restriction flag. -Its presence causes the restriction entry to be -matched only if the source port in the packet is the standard NTP -UDP port (123). -Both -\f\*[B-Font]ntpport\f[] -and -\f\*[B-Font]non-ntpport\f[] -may -be specified. -The -\f\*[B-Font]ntpport\f[] -is considered more specific and -is sorted later in the list. -.TP 7 -.NOP \f\*[B-Font]version\f[] -Deny packets that do not match the current NTP version. -.RE -.sp \n(Ppu -.ne 2 - -Default restriction list entries with the flags ignore, interface, -ntpport, for each of the local host's interface addresses are -inserted into the table at startup to prevent the server -from attempting to synchronize to its own time. -A default entry is also always present, though if it is -otherwise unconfigured; no flags are associated -with the default entry (i.e., everything besides your own -NTP server is unrestricted). -.PP -.SH Automatic NTP Configuration Options -.SS Manycasting -Manycasting is a automatic discovery and configuration paradigm -new to NTPv4. -It is intended as a means for a multicast client -to troll the nearby network neighborhood to find cooperating -manycast servers, validate them using cryptographic means -and evaluate their time values with respect to other servers -that might be lurking in the vicinity. -The intended result is that each manycast client mobilizes -client associations with some number of the "best" -of the nearby manycast servers, yet automatically reconfigures -to sustain this number of servers should one or another fail. -.sp \n(Ppu -.ne 2 - -Note that the manycasting paradigm does not coincide -with the anycast paradigm described in RFC-1546, -which is designed to find a single server from a clique -of servers providing the same service. -The manycast paradigm is designed to find a plurality -of redundant servers satisfying defined optimality criteria. -.sp \n(Ppu -.ne 2 - -Manycasting can be used with either symmetric key -or public key cryptography. -The public key infrastructure (PKI) -offers the best protection against compromised keys -and is generally considered stronger, at least with relatively -large key sizes. -It is implemented using the Autokey protocol and -the OpenSSL cryptographic library available from -\f[C]http://www.openssl.org/\f[]. -The library can also be used with other NTPv4 modes -as well and is highly recommended, especially for broadcast modes. -.sp \n(Ppu -.ne 2 - -A persistent manycast client association is configured -using the manycastclient command, which is similar to the -server command but with a multicast (IPv4 class -\f\*[B-Font]D\f[] -or IPv6 prefix -\f\*[B-Font]FF\f[]) -group address. -The IANA has designated IPv4 address 224.1.1.1 -and IPv6 address FF05::101 (site local) for NTP. -When more servers are needed, it broadcasts manycast -client messages to this address at the minimum feasible rate -and minimum feasible time-to-live (TTL) hops, depending -on how many servers have already been found. -There can be as many manycast client associations -as different group address, each one serving as a template -for a future ephemeral unicast client/server association. -.sp \n(Ppu -.ne 2 - -Manycast servers configured with the -\f\*[B-Font]manycastserver\f[] -command listen on the specified group address for manycast -client messages. -Note the distinction between manycast client, -which actively broadcasts messages, and manycast server, -which passively responds to them. -If a manycast server is -in scope of the current TTL and is itself synchronized -to a valid source and operating at a stratum level equal -to or lower than the manycast client, it replies to the -manycast client message with an ordinary unicast server message. -.sp \n(Ppu -.ne 2 - -The manycast client receiving this message mobilizes -an ephemeral client/server association according to the -matching manycast client template, but only if cryptographically -authenticated and the server stratum is less than or equal -to the client stratum. -Authentication is explicitly required -and either symmetric key or public key (Autokey) can be used. -Then, the client polls the server at its unicast address -in burst mode in order to reliably set the host clock -and validate the source. -This normally results -in a volley of eight client/server at 2-s intervals -during which both the synchronization and cryptographic -protocols run concurrently. -Following the volley, -the client runs the NTP intersection and clustering -algorithms, which act to discard all but the "best" -associations according to stratum and synchronization -distance. -The surviving associations then continue -in ordinary client/server mode. -.sp \n(Ppu -.ne 2 - -The manycast client polling strategy is designed to reduce -as much as possible the volume of manycast client messages -and the effects of implosion due to near-simultaneous -arrival of manycast server messages. -The strategy is determined by the -\f\*[B-Font]manycastclient\f[], -\f\*[B-Font]tos\f[] -and -\f\*[B-Font]ttl\f[] -configuration commands. -The manycast poll interval is -normally eight times the system poll interval, -which starts out at the -\f\*[B-Font]minpoll\f[] -value specified in the -\f\*[B-Font]manycastclient\f[], -command and, under normal circumstances, increments to the -\f\*[B-Font]maxpolll\f[] -value specified in this command. -Initially, the TTL is -set at the minimum hops specified by the ttl command. -At each retransmission the TTL is increased until reaching -the maximum hops specified by this command or a sufficient -number client associations have been found. -Further retransmissions use the same TTL. -.sp \n(Ppu -.ne 2 - -The quality and reliability of the suite of associations -discovered by the manycast client is determined by the NTP -mitigation algorithms and the -\f\*[B-Font]minclock\f[] -and -\f\*[B-Font]minsane\f[] -values specified in the -\f\*[B-Font]tos\f[] -configuration command. -At least -\f\*[B-Font]minsane\f[] -candidate servers must be available and the mitigation -algorithms produce at least -\f\*[B-Font]minclock\f[] -survivors in order to synchronize the clock. -Byzantine agreement principles require at least four -candidates in order to correctly discard a single falseticker. -For legacy purposes, -\f\*[B-Font]minsane\f[] -defaults to 1 and -\f\*[B-Font]minclock\f[] -defaults to 3. -For manycast service -\f\*[B-Font]minsane\f[] -should be explicitly set to 4, assuming at least that -number of servers are available. -.sp \n(Ppu -.ne 2 - -If at least -\f\*[B-Font]minclock\f[] -servers are found, the manycast poll interval is immediately -set to eight times -\f\*[B-Font]maxpoll\f[]. -If less than -\f\*[B-Font]minclock\f[] -servers are found when the TTL has reached the maximum hops, -the manycast poll interval is doubled. -For each transmission -after that, the poll interval is doubled again until -reaching the maximum of eight times -\f\*[B-Font]maxpoll\f[]. -Further transmissions use the same poll interval and -TTL values. -Note that while all this is going on, -each client/server association found is operating normally -it the system poll interval. -.sp \n(Ppu -.ne 2 - -Administratively scoped multicast boundaries are normally -specified by the network router configuration and, -in the case of IPv6, the link/site scope prefix. -By default, the increment for TTL hops is 32 starting -from 31; however, the -\f\*[B-Font]ttl\f[] -configuration command can be -used to modify the values to match the scope rules. -.sp \n(Ppu -.ne 2 - -It is often useful to narrow the range of acceptable -servers which can be found by manycast client associations. -Because manycast servers respond only when the client -stratum is equal to or greater than the server stratum, -primary (stratum 1) servers fill find only primary servers -in TTL range, which is probably the most common objective. -However, unless configured otherwise, all manycast clients -in TTL range will eventually find all primary servers -in TTL range, which is probably not the most common -objective in large networks. -The -\f\*[B-Font]tos\f[] -command can be used to modify this behavior. -Servers with stratum below -\f\*[B-Font]floor\f[] -or above -\f\*[B-Font]ceiling\f[] -specified in the -\f\*[B-Font]tos\f[] -command are strongly discouraged during the selection -process; however, these servers may be temporally -accepted if the number of servers within TTL range is -less than -\f\*[B-Font]minclock\f[]. -.sp \n(Ppu -.ne 2 - -The above actions occur for each manycast client message, -which repeats at the designated poll interval. -However, once the ephemeral client association is mobilized, -subsequent manycast server replies are discarded, -since that would result in a duplicate association. -If during a poll interval the number of client associations -falls below -\f\*[B-Font]minclock\f[], -all manycast client prototype associations are reset -to the initial poll interval and TTL hops and operation -resumes from the beginning. -It is important to avoid -frequent manycast client messages, since each one requires -all manycast servers in TTL range to respond. -The result could well be an implosion, either minor or major, -depending on the number of servers in range. -The recommended value for -\f\*[B-Font]maxpoll\f[] -is 12 (4,096 s). -.sp \n(Ppu -.ne 2 - -It is possible and frequently useful to configure a host -as both manycast client and manycast server. -A number of hosts configured this way and sharing a common -group address will automatically organize themselves -in an optimum configuration based on stratum and -synchronization distance. -For example, consider an NTP -subnet of two primary servers and a hundred or more -dependent clients. -With two exceptions, all servers -and clients have identical configuration files including both -\f\*[B-Font]multicastclient\f[] -and -\f\*[B-Font]multicastserver\f[] -commands using, for instance, multicast group address -239.1.1.1. -The only exception is that each primary server -configuration file must include commands for the primary -reference source such as a GPS receiver. -.sp \n(Ppu -.ne 2 - -The remaining configuration files for all secondary -servers and clients have the same contents, except for the -\f\*[B-Font]tos\f[] -command, which is specific for each stratum level. -For stratum 1 and stratum 2 servers, that command is -not necessary. -For stratum 3 and above servers the -\f\*[B-Font]floor\f[] -value is set to the intended stratum number. -Thus, all stratum 3 configuration files are identical, -all stratum 4 files are identical and so forth. -.sp \n(Ppu -.ne 2 - -Once operations have stabilized in this scenario, -the primary servers will find the primary reference source -and each other, since they both operate at the same -stratum (1), but not with any secondary server or client, -since these operate at a higher stratum. -The secondary -servers will find the servers at the same stratum level. -If one of the primary servers loses its GPS receiver, -it will continue to operate as a client and other clients -will time out the corresponding association and -re-associate accordingly. -.sp \n(Ppu -.ne 2 - -Some administrators prefer to avoid running -\fCntpd\fR(@NTPD_MS@)\f[] -continuously and run either -\fCntpdate\fR(8)\f[] -or -\fCntpd\fR(@NTPD_MS@)\f[] -\f\*[B-Font]\-q\f[] -as a cron job. -In either case the servers must be -configured in advance and the program fails if none are -available when the cron job runs. -A really slick -application of manycast is with -\fCntpd\fR(@NTPD_MS@)\f[] -\f\*[B-Font]\-q\f[]. -The program wakes up, scans the local landscape looking -for the usual suspects, selects the best from among -the rascals, sets the clock and then departs. -Servers do not have to be configured in advance and -all clients throughout the network can have the same -configuration file. -.SS Manycast Interactions with Autokey -Each time a manycast client sends a client mode packet -to a multicast group address, all manycast servers -in scope generate a reply including the host name -and status word. -The manycast clients then run -the Autokey protocol, which collects and verifies -all certificates involved. -Following the burst interval -all but three survivors are cast off, -but the certificates remain in the local cache. -It often happens that several complete signing trails -from the client to the primary servers are collected in this way. -.sp \n(Ppu -.ne 2 - -About once an hour or less often if the poll interval -exceeds this, the client regenerates the Autokey key list. -This is in general transparent in client/server mode. -However, about once per day the server private value -used to generate cookies is refreshed along with all -manycast client associations. -In this case all -cryptographic values including certificates is refreshed. -If a new certificate has been generated since -the last refresh epoch, it will automatically revoke -all prior certificates that happen to be in the -certificate cache. -At the same time, the manycast -scheme starts all over from the beginning and -the expanding ring shrinks to the minimum and increments -from there while collecting all servers in scope. -.SS Manycast Options -.TP 7 -.NOP \f\*[B-Font]tos\f[] [\f\*[B-Font]ceiling\f[] \f\*[I-Font]ceiling\f[] | \f\*[B-Font]cohort\f[] { \f\*[B-Font]0\f[] | \f\*[B-Font]1\f[] } | \f\*[B-Font]floor\f[] \f\*[I-Font]floor\f[] | \f\*[B-Font]minclock\f[] \f\*[I-Font]minclock\f[] | \f\*[B-Font]minsane\f[] \f\*[I-Font]minsane\f[]] -This command affects the clock selection and clustering -algorithms. -It can be used to select the quality and -quantity of peers used to synchronize the system clock -and is most useful in manycast mode. -The variables operate -as follows: -.RS -.TP 7 -.NOP \f\*[B-Font]ceiling\f[] \f\*[I-Font]ceiling\f[] -Peers with strata above -\f\*[B-Font]ceiling\f[] -will be discarded if there are at least -\f\*[B-Font]minclock\f[] -peers remaining. -This value defaults to 15, but can be changed -to any number from 1 to 15. -.TP 7 -.NOP \f\*[B-Font]cohort\f[] {0 | 1 } -This is a binary flag which enables (0) or disables (1) -manycast server replies to manycast clients with the same -stratum level. -This is useful to reduce implosions where -large numbers of clients with the same stratum level -are present. -The default is to enable these replies. -.TP 7 -.NOP \f\*[B-Font]floor\f[] \f\*[I-Font]floor\f[] -Peers with strata below -\f\*[B-Font]floor\f[] -will be discarded if there are at least -\f\*[B-Font]minclock\f[] -peers remaining. -This value defaults to 1, but can be changed -to any number from 1 to 15. -.TP 7 -.NOP \f\*[B-Font]minclock\f[] \f\*[I-Font]minclock\f[] -The clustering algorithm repeatedly casts out outlyer -associations until no more than -\f\*[B-Font]minclock\f[] -associations remain. -This value defaults to 3, -but can be changed to any number from 1 to the number of -configured sources. -.TP 7 -.NOP \f\*[B-Font]minsane\f[] \f\*[I-Font]minsane\f[] -This is the minimum number of candidates available -to the clock selection algorithm in order to produce -one or more truechimers for the clustering algorithm. -If fewer than this number are available, the clock is -undisciplined and allowed to run free. -The default is 1 -for legacy purposes. -However, according to principles of -Byzantine agreement, -\f\*[B-Font]minsane\f[] -should be at least 4 in order to detect and discard -a single falseticker. -.RE -.TP 7 -.NOP \f\*[B-Font]ttl\f[] \f\*[I-Font]hop\f[] \f\*[I-Font]...\f[] -This command specifies a list of TTL values in increasing -order, up to 8 values can be specified. -In manycast mode these values are used in turn -in an expanding-ring search. -The default is eight -multiples of 32 starting at 31. -.PP -.SH Reference Clock Support -The NTP Version 4 daemon supports some three dozen different radio, -satellite and modem reference clocks plus a special pseudo-clock -used for backup or when no other clock source is available. -Detailed descriptions of individual device drivers and options can -be found in the -"Reference Clock Drivers" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -Additional information can be found in the pages linked -there, including the -"Debugging Hints for Reference Clock Drivers" -and -"How To Write a Reference Clock Driver" -pages -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -In addition, support for a PPS -signal is available as described in the -"Pulse-per-second (PPS) Signal Interfacing" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -Many -drivers support special line discipline/streams modules which can -significantly improve the accuracy using the driver. -These are -described in the -"Line Disciplines and Streams Drivers" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.sp \n(Ppu -.ne 2 - -A reference clock will generally (though not always) be a radio -timecode receiver which is synchronized to a source of standard -time such as the services offered by the NRC in Canada and NIST and -USNO in the US. -The interface between the computer and the timecode -receiver is device dependent, but is usually a serial port. -A -device driver specific to each reference clock must be selected and -compiled in the distribution; however, most common radio, satellite -and modem clocks are included by default. -Note that an attempt to -configure a reference clock when the driver has not been compiled -or the hardware port has not been appropriately configured results -in a scalding remark to the system log file, but is otherwise non -hazardous. -.sp \n(Ppu -.ne 2 - -For the purposes of configuration, -\fCntpd\fR(@NTPD_MS@)\f[] -treats -reference clocks in a manner analogous to normal NTP peers as much -as possible. -Reference clocks are identified by a syntactically -correct but invalid IP address, in order to distinguish them from -normal NTP peers. -Reference clock addresses are of the form -\f[C]127.127.\f[]\f\*[I-Font]t\f[].\f\*[I-Font]u\f[], -where -\f\*[I-Font]t\f[] -is an integer -denoting the clock type and -\f\*[I-Font]u\f[] -indicates the unit -number in the range 0-3. -While it may seem overkill, it is in fact -sometimes useful to configure multiple reference clocks of the same -type, in which case the unit numbers must be unique. -.sp \n(Ppu -.ne 2 - -The -\f\*[B-Font]server\f[] -command is used to configure a reference -clock, where the -\f\*[I-Font]address\f[] -argument in that command -is the clock address. -The -\f\*[B-Font]key\f[], -\f\*[B-Font]version\f[] -and -\f\*[B-Font]ttl\f[] -options are not used for reference clock support. -The -\f\*[B-Font]mode\f[] -option is added for reference clock support, as -described below. -The -\f\*[B-Font]prefer\f[] -option can be useful to -persuade the server to cherish a reference clock with somewhat more -enthusiasm than other reference clocks or peers. -Further -information on this option can be found in the -"Mitigation Rules and the prefer Keyword" -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]) -page. -The -\f\*[B-Font]minpoll\f[] -and -\f\*[B-Font]maxpoll\f[] -options have -meaning only for selected clock drivers. -See the individual clock -driver document pages for additional information. -.sp \n(Ppu -.ne 2 - -The -\f\*[B-Font]fudge\f[] -command is used to provide additional -information for individual clock drivers and normally follows -immediately after the -\f\*[B-Font]server\f[] -command. -The -\f\*[I-Font]address\f[] -argument specifies the clock address. -The -\f\*[B-Font]refid\f[] -and -\f\*[B-Font]stratum\f[] -options can be used to -override the defaults for the device. -There are two optional -device-dependent time offsets and four flags that can be included -in the -\f\*[B-Font]fudge\f[] -command as well. -.sp \n(Ppu -.ne 2 - -The stratum number of a reference clock is by default zero. -Since the -\fCntpd\fR(@NTPD_MS@)\f[] -daemon adds one to the stratum of each -peer, a primary server ordinarily displays an external stratum of -one. -In order to provide engineered backups, it is often useful to -specify the reference clock stratum as greater than zero. -The -\f\*[B-Font]stratum\f[] -option is used for this purpose. -Also, in cases -involving both a reference clock and a pulse-per-second (PPS) -discipline signal, it is useful to specify the reference clock -identifier as other than the default, depending on the driver. -The -\f\*[B-Font]refid\f[] -option is used for this purpose. -Except where noted, -these options apply to all clock drivers. -.SS Reference Clock Commands -.TP 7 -.NOP \f\*[B-Font]server\f[] \f[C]127.127.\f[]\f\*[I-Font]t\f[].\f\*[I-Font]u\f[] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]mode\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]int\f[]] -This command can be used to configure reference clocks in -special ways. -The options are interpreted as follows: -.RS -.TP 7 -.NOP \f\*[B-Font]prefer\f[] -Marks the reference clock as preferred. -All other things being -equal, this host will be chosen for synchronization among a set of -correctly operating hosts. -See the -"Mitigation Rules and the prefer Keyword" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]) -for further information. -.TP 7 -.NOP \f\*[B-Font]mode\f[] \f\*[I-Font]int\f[] -Specifies a mode number which is interpreted in a -device-specific fashion. -For instance, it selects a dialing -protocol in the ACTS driver and a device subtype in the -parse -drivers. -.TP 7 -.NOP \f\*[B-Font]minpoll\f[] \f\*[I-Font]int\f[] -.TP 7 -.NOP \f\*[B-Font]maxpoll\f[] \f\*[I-Font]int\f[] -These options specify the minimum and maximum polling interval -for reference clock messages, as a power of 2 in seconds -For -most directly connected reference clocks, both -\f\*[B-Font]minpoll\f[] -and -\f\*[B-Font]maxpoll\f[] -default to 6 (64 s). -For modem reference clocks, -\f\*[B-Font]minpoll\f[] -defaults to 10 (17.1 m) and -\f\*[B-Font]maxpoll\f[] -defaults to 14 (4.5 h). -The allowable range is 4 (16 s) to 17 (36.4 h) inclusive. -.RE -.TP 7 -.NOP \f\*[B-Font]fudge\f[] \f[C]127.127.\f[]\f\*[I-Font]t\f[].\f\*[I-Font]u\f[] [\f\*[B-Font]time1\f[] \f\*[I-Font]sec\f[]] [\f\*[B-Font]time2\f[] \f\*[I-Font]sec\f[]] [\f\*[B-Font]stratum\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]refid\f[] \f\*[I-Font]string\f[]] [\f\*[B-Font]mode\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]flag1\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[]] [\f\*[B-Font]flag2\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[]] [\f\*[B-Font]flag3\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[]] [\f\*[B-Font]flag4\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[]] -This command can be used to configure reference clocks in -special ways. -It must immediately follow the -\f\*[B-Font]server\f[] -command which configures the driver. -Note that the same capability -is possible at run time using the -\fCntpdc\fR(@NTPDC_MS@)\f[] -program. -The options are interpreted as -follows: -.RS -.TP 7 -.NOP \f\*[B-Font]time1\f[] \f\*[I-Font]sec\f[] -Specifies a constant to be added to the time offset produced by -the driver, a fixed-point decimal number in seconds. -This is used -as a calibration constant to adjust the nominal time offset of a -particular clock to agree with an external standard, such as a -precision PPS signal. -It also provides a way to correct a -systematic error or bias due to serial port or operating system -latencies, different cable lengths or receiver internal delay. -The -specified offset is in addition to the propagation delay provided -by other means, such as internal DIPswitches. -Where a calibration -for an individual system and driver is available, an approximate -correction is noted in the driver documentation pages. -Note: in order to facilitate calibration when more than one -radio clock or PPS signal is supported, a special calibration -feature is available. -It takes the form of an argument to the -\f\*[B-Font]enable\f[] -command described in -\fIMiscellaneous\f[] \fIOptions\f[] -page and operates as described in the -"Reference Clock Drivers" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.TP 7 -.NOP \f\*[B-Font]time2\f[] \f\*[I-Font]secs\f[] -Specifies a fixed-point decimal number in seconds, which is -interpreted in a driver-dependent way. -See the descriptions of -specific drivers in the -"Reference Clock Drivers" -page -(available as part of the HTML documentation -provided in -\fI/usr/share/doc/ntp\f[]). -.TP 7 -.NOP \f\*[B-Font]stratum\f[] \f\*[I-Font]int\f[] -Specifies the stratum number assigned to the driver, an integer -between 0 and 15. -This number overrides the default stratum number -ordinarily assigned by the driver itself, usually zero. -.TP 7 -.NOP \f\*[B-Font]refid\f[] \f\*[I-Font]string\f[] -Specifies an ASCII string of from one to four characters which -defines the reference identifier used by the driver. -This string -overrides the default identifier ordinarily assigned by the driver -itself. -.TP 7 -.NOP \f\*[B-Font]mode\f[] \f\*[I-Font]int\f[] -Specifies a mode number which is interpreted in a -device-specific fashion. -For instance, it selects a dialing -protocol in the ACTS driver and a device subtype in the -parse -drivers. -.TP 7 -.NOP \f\*[B-Font]flag1\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[] -.TP 7 -.NOP \f\*[B-Font]flag2\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[] -.TP 7 -.NOP \f\*[B-Font]flag3\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[] -.TP 7 -.NOP \f\*[B-Font]flag4\f[] \f\*[B-Font]0\f[] \f\*[B-Font]\&|\f[] \f\*[B-Font]1\f[] -These four flags are used for customizing the clock driver. -The -interpretation of these values, and whether they are used at all, -is a function of the particular clock driver. -However, by -convention -\f\*[B-Font]flag4\f[] -is used to enable recording monitoring -data to the -\f\*[B-Font]clockstats\f[] -file configured with the -\f\*[B-Font]filegen\f[] -command. -Further information on the -\f\*[B-Font]filegen\f[] -command can be found in -\fIMonitoring\f[] \fIOptions\f[]. -.RE -.PP -.SH Miscellaneous Options -.TP 7 -.NOP \f\*[B-Font]broadcastdelay\f[] \f\*[I-Font]seconds\f[] -The broadcast and multicast modes require a special calibration -to determine the network delay between the local and remote -servers. -Ordinarily, this is done automatically by the initial -protocol exchanges between the client and server. -In some cases, -the calibration procedure may fail due to network or server access -controls, for example. -This command specifies the default delay to -be used under these circumstances. -Typically (for Ethernet), a -number between 0.003 and 0.007 seconds is appropriate. -The default -when this command is not used is 0.004 seconds. -.TP 7 -.NOP \f\*[B-Font]calldelay\f[] \f\*[I-Font]delay\f[] -This option controls the delay in seconds between the first and second -packets sent in burst or iburst mode to allow additional time for a modem -or ISDN call to complete. -.TP 7 -.NOP \f\*[B-Font]driftfile\f[] \f\*[I-Font]driftfile\f[] -This command specifies the complete path and name of the file used to -record the frequency of the local clock oscillator. -This is the same -operation as the -\f\*[B-Font]\-f\f[] -command line option. -If the file exists, it is read at -startup in order to set the initial frequency and then updated once per -hour with the current frequency computed by the daemon. -If the file name is -specified, but the file itself does not exist, the starts with an initial -frequency of zero and creates the file when writing it for the first time. -If this command is not given, the daemon will always start with an initial -frequency of zero. -.sp \n(Ppu -.ne 2 - -The file format consists of a single line containing a single -floating point number, which records the frequency offset measured -in parts-per-million (PPM). -The file is updated by first writing -the current drift value into a temporary file and then renaming -this file to replace the old version. -This implies that -\fCntpd\fR(@NTPD_MS@)\f[] -must have write permission for the directory the -drift file is located in, and that file system links, symbolic or -otherwise, should be avoided. -.TP 7 -.NOP \f\*[B-Font]enable\f[] [\f\*[B-Font]auth\f[] | \f\*[B-Font]bclient\f[] | \f\*[B-Font]calibrate\f[] | \f\*[B-Font]kernel\f[] | \f\*[B-Font]mode7\f[] | \f\*[B-Font]monitor\f[] | \f\*[B-Font]ntp\f[] | \f\*[B-Font]stats\f[]] -.TP 7 -.NOP \f\*[B-Font]disable\f[] [\f\*[B-Font]auth\f[] | \f\*[B-Font]bclient\f[] | \f\*[B-Font]calibrate\f[] | \f\*[B-Font]kernel\f[] | \f\*[B-Font]mode7\f[] | \f\*[B-Font]monitor\f[] | \f\*[B-Font]ntp\f[] | \f\*[B-Font]stats\f[]] -Provides a way to enable or disable various server options. -Flags not mentioned are unaffected. -Note that all of these flags -can be controlled remotely using the -\fCntpdc\fR(@NTPDC_MS@)\f[] -utility program. -.RS -.TP 7 -.NOP \f\*[B-Font]auth\f[] -Enables the server to synchronize with unconfigured peers only if the -peer has been correctly authenticated using either public key or -private key cryptography. -The default for this flag is -\f\*[B-Font]enable\f[]. -.TP 7 -.NOP \f\*[B-Font]bclient\f[] -Enables the server to listen for a message from a broadcast or -multicast server, as in the -\f\*[B-Font]multicastclient\f[] -command with default -address. -The default for this flag is -\f\*[B-Font]disable\f[]. -.TP 7 -.NOP \f\*[B-Font]calibrate\f[] -Enables the calibrate feature for reference clocks. -The default for -this flag is -\f\*[B-Font]disable\f[]. -.TP 7 -.NOP \f\*[B-Font]kernel\f[] -Enables the kernel time discipline, if available. -The default for this -flag is -\f\*[B-Font]enable\f[] -if support is available, otherwise -\f\*[B-Font]disable\f[]. -.TP 7 -.NOP \f\*[B-Font]mode7\f[] -Enables processing of NTP mode 7 implementation-specific requests -which are used by the deprecated -\fCntpdc\fR(@NTPDC_MS@)\f[] -program. -The default for this flag is disable. -This flag is excluded from runtime configuration using -\fCntpq\fR(@NTPQ_MS@)\f[]. -The -\fCntpq\fR(@NTPQ_MS@)\f[] -program provides the same capabilities as -\fCntpdc\fR(@NTPDC_MS@)\f[] -using standard mode 6 requests. -.TP 7 -.NOP \f\*[B-Font]monitor\f[] -Enables the monitoring facility. -See the -\fCntpdc\fR(@NTPDC_MS@)\f[] -program -and the -\f\*[B-Font]monlist\f[] -command or further information. -The -default for this flag is -\f\*[B-Font]enable\f[]. -.TP 7 -.NOP \f\*[B-Font]ntp\f[] -Enables time and frequency discipline. -In effect, this switch opens and -closes the feedback loop, which is useful for testing. -The default for -this flag is -\f\*[B-Font]enable\f[]. -.TP 7 -.NOP \f\*[B-Font]stats\f[] -Enables the statistics facility. -See the -\fIMonitoring\f[] \fIOptions\f[] -section for further information. -The default for this flag is -\f\*[B-Font]disable\f[]. -.RE -.TP 7 -.NOP \f\*[B-Font]includefile\f[] \f\*[I-Font]includefile\f[] -This command allows additional configuration commands -to be included from a separate file. -Include files may -be nested to a depth of five; upon reaching the end of any -include file, command processing resumes in the previous -configuration file. -This option is useful for sites that run -\fCntpd\fR(@NTPD_MS@)\f[] -on multiple hosts, with (mostly) common options (e.g., a -restriction list). -.TP 7 -.NOP \f\*[B-Font]logconfig\f[] \f\*[I-Font]configkeyword\f[] -This command controls the amount and type of output written to -the system -\fCsyslog\fR(3)\f[] -facility or the alternate -\f\*[B-Font]logfile\f[] -log file. -By default, all output is turned on. -All -\f\*[I-Font]configkeyword\f[] -keywords can be prefixed with -\[oq]=\[cq], -\[oq]+\[cq] -and -\[oq]\-\[cq], -where -\[oq]=\[cq] -sets the -\fCsyslog\fR(3)\f[] -priority mask, -\[oq]+\[cq] -adds and -\[oq]\-\[cq] -removes -messages. -\fCsyslog\fR(3)\f[] -messages can be controlled in four -classes -(\f\*[B-Font]clock\f[], \f\*[B-Font]peer\f[], \f\*[B-Font]sys\f[] and \f\*[B-Font]sync\f[]). -Within these classes four types of messages can be -controlled: informational messages -(\f\*[B-Font]info\f[]), -event messages -(\f\*[B-Font]events\f[]), -statistics messages -(\f\*[B-Font]statistics\f[]) -and -status messages -(\f\*[B-Font]status\f[]). -.sp \n(Ppu -.ne 2 - -Configuration keywords are formed by concatenating the message class with -the event class. -The -\f\*[B-Font]all\f[] -prefix can be used instead of a message class. -A -message class may also be followed by the -\f\*[B-Font]all\f[] -keyword to enable/disable all -messages of the respective message class.Thus, a minimal log configuration -could look like this: -.br -.in +4 -.nf -logconfig =syncstatus +sysevents -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -This would just list the synchronizations state of -\fCntpd\fR(@NTPD_MS@)\f[] -and the major system events. -For a simple reference server, the -following minimum message configuration could be useful: -.br -.in +4 -.nf -logconfig =syncall +clockall -.in -4 -.fi -.sp \n(Ppu -.ne 2 - -This configuration will list all clock information and -synchronization information. -All other events and messages about -peers, system events and so on is suppressed. -.TP 7 -.NOP \f\*[B-Font]logfile\f[] \f\*[I-Font]logfile\f[] -This command specifies the location of an alternate log file to -be used instead of the default system -\fCsyslog\fR(3)\f[] -facility. -This is the same operation as the \-l command line option. -.TP 7 -.NOP \f\*[B-Font]setvar\f[] \f\*[I-Font]variable\f[] [\f\*[B-Font]default\f[]] -This command adds an additional system variable. -These -variables can be used to distribute additional information such as -the access policy. -If the variable of the form -\fIname\f[]\fI=\f[]\f\*[I-Font]value\f[] -is followed by the -\f\*[B-Font]default\f[] -keyword, the -variable will be listed as part of the default system variables -(\fCntpq\fR(@NTPQ_MS@)\f[] \f\*[B-Font]rv\f[] command)). -These additional variables serve -informational purposes only. -They are not related to the protocol -other that they can be listed. -The known protocol variables will -always override any variables defined via the -\f\*[B-Font]setvar\f[] -mechanism. -There are three special variables that contain the names -of all variable of the same group. -The -\fIsys_var_list\f[] -holds -the names of all system variables. -The -\fIpeer_var_list\f[] -holds -the names of all peer variables and the -\fIclock_var_list\f[] -holds the names of the reference clock variables. -.TP 7 -.NOP \f\*[B-Font]tinker\f[] [\f\*[B-Font]allan\f[] \f\*[I-Font]allan\f[] | \f\*[B-Font]dispersion\f[] \f\*[I-Font]dispersion\f[] | \f\*[B-Font]freq\f[] \f\*[I-Font]freq\f[] | \f\*[B-Font]huffpuff\f[] \f\*[I-Font]huffpuff\f[] | \f\*[B-Font]panic\f[] \f\*[I-Font]panic\f[] | \f\*[B-Font]step\f[] \f\*[I-Font]srep\f[] | \f\*[B-Font]stepout\f[] \f\*[I-Font]stepout\f[]] -This command can be used to alter several system variables in -very exceptional circumstances. -It should occur in the -configuration file before any other configuration options. -The -default values of these variables have been carefully optimized for -a wide range of network speeds and reliability expectations. -In -general, they interact in intricate ways that are hard to predict -and some combinations can result in some very nasty behavior. -Very -rarely is it necessary to change the default values; but, some -folks cannot resist twisting the knobs anyway and this command is -for them. -Emphasis added: twisters are on their own and can expect -no help from the support group. -.sp \n(Ppu -.ne 2 - -The variables operate as follows: -.RS -.TP 7 -.NOP \f\*[B-Font]allan\f[] \f\*[I-Font]allan\f[] -The argument becomes the new value for the minimum Allan -intercept, which is a parameter of the PLL/FLL clock discipline -algorithm. -The value in log2 seconds defaults to 7 (1024 s), which is also the lower -limit. -.TP 7 -.NOP \f\*[B-Font]dispersion\f[] \f\*[I-Font]dispersion\f[] -The argument becomes the new value for the dispersion increase rate, -normally .000015 s/s. -.TP 7 -.NOP \f\*[B-Font]freq\f[] \f\*[I-Font]freq\f[] -The argument becomes the initial value of the frequency offset in -parts-per-million. -This overrides the value in the frequency file, if -present, and avoids the initial training state if it is not. -.TP 7 -.NOP \f\*[B-Font]huffpuff\f[] \f\*[I-Font]huffpuff\f[] -The argument becomes the new value for the experimental -huff-n'-puff filter span, which determines the most recent interval -the algorithm will search for a minimum delay. -The lower limit is -900 s (15 m), but a more reasonable value is 7200 (2 hours). -There -is no default, since the filter is not enabled unless this command -is given. -.TP 7 -.NOP \f\*[B-Font]panic\f[] \f\*[I-Font]panic\f[] -The argument is the panic threshold, normally 1000 s. -If set to zero, -the panic sanity check is disabled and a clock offset of any value will -be accepted. -.TP 7 -.NOP \f\*[B-Font]step\f[] \f\*[I-Font]step\f[] -The argument is the step threshold, which by default is 0.128 s. -It can -be set to any positive number in seconds. -If set to zero, step -adjustments will never occur. -Note: The kernel time discipline is -disabled if the step threshold is set to zero or greater than the -default. -.TP 7 -.NOP \f\*[B-Font]stepout\f[] \f\*[I-Font]stepout\f[] -The argument is the stepout timeout, which by default is 900 s. -It can -be set to any positive number in seconds. -If set to zero, the stepout -pulses will not be suppressed. -.RE -.TP 7 -.NOP \f\*[B-Font]rlimit\f[] [\f\*[B-Font]memlock\f[] \f\*[I-Font]Nmegabytes\f[] | \f\*[B-Font]stacksize\f[] \f\*[I-Font]N4kPages\f[] \f\*[B-Font]filenum\f[] \f\*[I-Font]Nfiledescriptors\f[]] -.RS -.TP 7 -.NOP \f\*[B-Font]memlock\f[] \f\*[I-Font]Nmegabytes\f[] -Specify the number of megabytes of memory that can be allocated. -Probably only available under Linux, this option is useful -when dropping root (the -\f\*[B-Font]\-i\f[] -option). -The default is 32 megabytes. Setting this to zero will prevent any attemp to lock memory. -.TP 7 -.NOP \f\*[B-Font]stacksize\f[] \f\*[I-Font]N4kPages\f[] -Specifies the maximum size of the process stack on systems with the -.TP 7 -.NOP \f\*[B-Font]filenum\f[] \f\*[I-Font]Nfiledescriptors\f[] -Specifies the maximum number of file descriptors ntpd may have open at once. Defaults to the system default. -\fBmlockall\fR()\f[] -function. -Defaults to 50 4k pages (200 4k pages in OpenBSD). -.RE -.TP 7 -.NOP \f\*[B-Font]trap\f[] \f\*[I-Font]host_address\f[] [\f\*[B-Font]port\f[] \f\*[I-Font]port_number\f[]] [\f\*[B-Font]interface\f[] \f\*[I-Font]interface_address\f[]] -This command configures a trap receiver at the given host -address and port number for sending messages with the specified -local interface address. -If the port number is unspecified, a value -of 18447 is used. -If the interface address is not specified, the -message is sent with a source address of the local interface the -message is sent through. -Note that on a multihomed host the -interface used may vary from time to time with routing changes. -.sp \n(Ppu -.ne 2 - -The trap receiver will generally log event messages and other -information from the server in a log file. -While such monitor -programs may also request their own trap dynamically, configuring a -trap receiver will ensure that no messages are lost when the server -is started. -.TP 7 -.NOP \f\*[B-Font]hop\f[] \f\*[I-Font]...\f[] -This command specifies a list of TTL values in increasing order, up to 8 -values can be specified. -In manycast mode these values are used in turn in -an expanding-ring search. -The default is eight multiples of 32 starting at -31. -.PP -.SH "OPTIONS" -.TP -.NOP \f\*[B-Font]\-\-help\f[] -Display usage information and exit. -.TP -.NOP \f\*[B-Font]\-\-more-help\f[] -Pass the extended usage information through a pager. -.TP -.NOP \f\*[B-Font]\-\-version\f[] [{\f\*[I-Font]v|c|n\f[]}] -Output version of program and exit. The default mode is `v', a simple -version. The `c' mode will print copyright information and `n' will -print the full copyright notice. -.PP -.SH "OPTION PRESETS" -Any option that is not marked as \fInot presettable\fP may be preset -by loading values from environment variables named: -.nf - \fBNTP_CONF_\fP or \fBNTP_CONF\fP -.fi -.ad -.TH ntp.conf 5 "02 Apr 2014" "4.2.7p439" "File Formats" -.\" -.\" EDIT THIS FILE WITH CAUTION (/tmp/.ag-QxaqsZ/ag-CyaqrZ) -.\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:09 AM by AutoGen 5.18.3pre18 -.\" From the definitions ntp.conf.def -.\" and the template file agman-cmd.tpl -.SH NAME -\f\*[B-Font]ntp.conf\fP ntp.conf -\- Network Time Protocol (NTP) daemon configuration file format -cvt_prog='/usr/local/gnu/share/autogen/texi2man' -cvt_prog=`cd \`dirname "$cvt_prog"\` >/dev/null && pwd - `/`basename "$cvt_prog"` -cd $tmp_dir -test \-x "$cvt_prog" || die "'$cvt_prog' is not executable" -{ - list='synopsis description options option-presets' - for f in $list ; do cat $f ; echo ; done - rm \-f $list name - list='implementation-notes environment files examples exit-status errors - compatibility see-also conforming-to history authors copyright bugs - notes' - for f in $list ; do cat $f ; echo ; done > .end-doc - rm \-f $list - list=`ls \-1 *`' .end-doc' - for f in $list ; do cat $f ; echo ; done - rm \-f $list -} 1>.doc 2>/dev/null -/opt/csw/bin/ggrep \-E \-v '^[ ]*$' .doc | $cvt_prog -.SH "ENVIRONMENT" -See \fBOPTION PRESETS\fP for configuration environment variables. -.SH FILES -.TP 15 -.NOP \fI/etc/ntp.conf\f[] -the default name of the configuration file -.br -.ns -.TP 15 -.NOP \fIntp.keys\f[] -private MD5 keys -.br -.ns -.TP 15 -.NOP \fIntpkey\f[] -RSA private key -.br -.ns -.TP 15 -.NOP \fIntpkey_\f[]\f\*[I-Font]host\f[] -RSA public key -.br -.ns -.TP 15 -.NOP \fIntp_dh\f[] -Diffie-Hellman agreement parameters -.PP -.SH "EXIT STATUS" -One of the following exit values will be returned: -.TP -.NOP 0 " (EXIT_SUCCESS)" -Successful program execution. -.TP -.NOP 1 " (EXIT_FAILURE)" -The operation failed or the command syntax was not valid. -.TP -.NOP 70 " (EX_SOFTWARE)" -libopts had an internal operational error. Please report -it to autogen-users@lists.sourceforge.net. Thank you. -.PP -.SH "SEE ALSO" -\fCntpd\fR(@NTPD_MS@)\f[], -\fCntpdc\fR(@NTPDC_MS@)\f[], -\fCntpq\fR(@NTPQ_MS@)\f[] -.sp \n(Ppu -.ne 2 - -In addition to the manual pages provided, -comprehensive documentation is available on the world wide web -at -\f[C]http://www.ntp.org/\f[]. -A snapshot of this documentation is available in HTML format in -\fI/usr/share/doc/ntp\f[]. -David L. Mills, -\fINetwork Time Protocol (Version 4)\fR, -RFC5905 -.PP - -.SH "AUTHORS" -The University of Delaware -.SH "COPYRIGHT" -Copyright (C) 1970-2013 The University of Delaware all rights reserved. -This program is released under the terms of the NTP license, . -.SH BUGS -The syntax checking is not picky; some combinations of -ridiculous and even hilarious options and modes may not be -detected. -.sp \n(Ppu -.ne 2 - -The -\fIntpkey_\f[]\f\*[I-Font]host\f[] -files are really digital -certificates. -These should be obtained via secure directory -services when they become universally available. -.sp \n(Ppu -.ne 2 - -Please send bug reports to: http://bugs.ntp.org, bugs@ntp.org -.SH NOTES -This document was derived from FreeBSD. -.sp \n(Ppu -.ne 2 - -This manual page was \fIAutoGen\fP-erated from the \fBntp.conf\fP -option definitions. diff --git a/ntpd/ntp.conf.mdoc.in b/ntpd/ntp.conf.mdoc.in index 357c1e026..6b1b64195 100644 --- a/ntpd/ntp.conf.mdoc.in +++ b/ntpd/ntp.conf.mdoc.in @@ -1,9 +1,9 @@ -.Dd April 2 2014 +.Dd April 9 2014 .Dt NTP_CONF 5 File Formats .Os .\" EDIT THIS FILE WITH CAUTION (ntp.mdoc) .\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:43 AM by AutoGen 5.18.3pre18 +.\" It has been AutoGen-ed April 9, 2014 at 10:03:46 AM by AutoGen 5.18.3pre18 .\" From the definitions ntp.conf.def .\" and the template file agmdoc-cmd.tpl .Sh NAME diff --git a/ntpd/ntp.keys.5man b/ntpd/ntp.keys.5man index d996cedec..06872bf4e 100644 --- a/ntpd/ntp.keys.5man +++ b/ntpd/ntp.keys.5man @@ -1,8 +1,8 @@ -.TH ntp.keys 5man "02 Apr 2014" "4.2.7p439" "File Formats" +.TH ntp.keys 5man "09 Apr 2014" "4.2.7p440" "File Formats" .\" .\" EDIT THIS FILE WITH CAUTION (ntp.man) .\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:21 AM by AutoGen 5.18.3pre18 +.\" It has been AutoGen-ed April 9, 2014 at 10:03:18 AM by AutoGen 5.18.3pre18 .\" From the definitions ntp.keys.def .\" and the template file agman-file.tpl .Sh NAME diff --git a/ntpd/ntp.keys.5mdoc b/ntpd/ntp.keys.5mdoc index bebd8e9f3..3f82ba227 100644 --- a/ntpd/ntp.keys.5mdoc +++ b/ntpd/ntp.keys.5mdoc @@ -1,9 +1,9 @@ -.Dd April 2 2014 +.Dd April 9 2014 .Dt NTP_KEYS 5mdoc File Formats .Os SunOS 5.10 .\" EDIT THIS FILE WITH CAUTION (ntp.mdoc) .\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:48 AM by AutoGen 5.18.3pre18 +.\" It has been AutoGen-ed April 9, 2014 at 10:03:50 AM by AutoGen 5.18.3pre18 .\" From the definitions ntp.keys.def .\" and the template file agmdoc-file.tpl .Sh NAME diff --git a/ntpd/ntp.keys.html b/ntpd/ntp.keys.html index ae0b1e5cb..ec45a1514 100644 --- a/ntpd/ntp.keys.html +++ b/ntpd/ntp.keys.html @@ -33,7 +33,7 @@ Up: (dir)

This document describes the symmetric key file for the NTP Project's ntpd program. -

This document applies to version 4.2.7p439 of ntp.keys. +

This document applies to version 4.2.7p440 of ntp.keys.

Short Contents

diff --git a/ntpd/ntp.keys.man.in b/ntpd/ntp.keys.man.in index cee7679a2..0f1abf18a 100644 --- a/ntpd/ntp.keys.man.in +++ b/ntpd/ntp.keys.man.in @@ -1,8 +1,8 @@ -.TH ntp.keys 5 "02 Apr 2014" "4.2.7p439" "File Formats" +.TH ntp.keys 5 "09 Apr 2014" "4.2.7p440" "File Formats" .\" .\" EDIT THIS FILE WITH CAUTION (ntp.man) .\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:21 AM by AutoGen 5.18.3pre18 +.\" It has been AutoGen-ed April 9, 2014 at 10:03:18 AM by AutoGen 5.18.3pre18 .\" From the definitions ntp.keys.def .\" and the template file agman-file.tpl .Sh NAME diff --git a/ntpd/ntp.keys.mdoc.in b/ntpd/ntp.keys.mdoc.in index 65aea3f8c..aeaa66955 100644 --- a/ntpd/ntp.keys.mdoc.in +++ b/ntpd/ntp.keys.mdoc.in @@ -1,9 +1,9 @@ -.Dd April 2 2014 +.Dd April 9 2014 .Dt NTP_KEYS 5 File Formats .Os SunOS 5.10 .\" EDIT THIS FILE WITH CAUTION (ntp.mdoc) .\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:48 AM by AutoGen 5.18.3pre18 +.\" It has been AutoGen-ed April 9, 2014 at 10:03:50 AM by AutoGen 5.18.3pre18 .\" From the definitions ntp.keys.def .\" and the template file agmdoc-file.tpl .Sh NAME diff --git a/ntpd/ntpd-opts.c b/ntpd/ntpd-opts.c index 0765f79ac..3d7442c74 100644 --- a/ntpd/ntpd-opts.c +++ b/ntpd/ntpd-opts.c @@ -1,7 +1,7 @@ /* * EDIT THIS FILE WITH CAUTION (ntpd-opts.c) * - * It has been AutoGen-ed April 2, 2014 at 10:43:11 AM by AutoGen 5.18.3pre18 + * It has been AutoGen-ed April 8, 2014 at 11:31:40 AM by AutoGen 5.18.3pre18 * From the definitions ntpd-opts.def * and the template file options * @@ -75,7 +75,7 @@ extern FILE * option_usage_fp; * static const strings for ntpd options */ static char const ntpd_opt_strs[3011] = -/* 0 */ "ntpd 4.2.7p439\n" +/* 0 */ "ntpd 4.2.7p440\n" "Copyright (C) 1970-2013 The University of Delaware, all rights reserved.\n" "This is free software. It is licensed for use, modification and\n" "redistribution under the terms of the NTP License, copies of which\n" @@ -201,12 +201,12 @@ static char const ntpd_opt_strs[3011] = /* 2778 */ "output version information and exit\0" /* 2814 */ "version\0" /* 2822 */ "NTPD\0" -/* 2827 */ "ntpd - NTP daemon program - Ver. 4.2.7p439\n" +/* 2827 */ "ntpd - NTP daemon program - Ver. 4.2.7p440\n" "Usage: %s [ - [] | --[{=| }] ]... \\\n" "\t\t[ ... ]\n\0" /* 2960 */ "http://bugs.ntp.org, bugs@ntp.org\0" /* 2994 */ "\n\0" -/* 2996 */ "ntpd 4.2.7p439"; +/* 2996 */ "ntpd 4.2.7p440"; /** * ipv4 option description with @@ -1558,7 +1558,7 @@ static void bogus_function(void) { translate option names. */ /* referenced via ntpdOptions.pzCopyright */ - puts(_("ntpd 4.2.7p439\n\ + puts(_("ntpd 4.2.7p440\n\ Copyright (C) 1970-2013 The University of Delaware, all rights reserved.\n\ This is free software. It is licensed for use, modification and\n\ redistribution under the terms of the NTP License, copies of which\n\ @@ -1695,7 +1695,7 @@ provided \"as is\" without express or implied warranty.\n")); puts(_("output version information and exit")); /* referenced via ntpdOptions.pzUsageTitle */ - puts(_("ntpd - NTP daemon program - Ver. 4.2.7p439\n\ + puts(_("ntpd - NTP daemon program - Ver. 4.2.7p440\n\ Usage: %s [ - [] | --[{=| }] ]... \\\n\ \t\t[ ... ]\n")); @@ -1703,7 +1703,7 @@ Usage: %s [ - [] | --[{=| }] ]... \\\n\ puts(_("\n")); /* referenced via ntpdOptions.pzFullVersion */ - puts(_("ntpd 4.2.7p439")); + puts(_("ntpd 4.2.7p440")); /* referenced via ntpdOptions.pzFullUsage */ puts(_("<<>>")); diff --git a/ntpd/ntpd-opts.h b/ntpd/ntpd-opts.h index f63182c2c..e849588a1 100644 --- a/ntpd/ntpd-opts.h +++ b/ntpd/ntpd-opts.h @@ -1,7 +1,7 @@ /* * EDIT THIS FILE WITH CAUTION (ntpd-opts.h) * - * It has been AutoGen-ed April 2, 2014 at 10:43:09 AM by AutoGen 5.18.3pre18 + * It has been AutoGen-ed April 8, 2014 at 11:31:38 AM by AutoGen 5.18.3pre18 * From the definitions ntpd-opts.def * and the template file options * @@ -105,9 +105,9 @@ typedef enum { /** count of all options for ntpd */ #define OPTION_CT 37 /** ntpd version */ -#define NTPD_VERSION "4.2.7p439" +#define NTPD_VERSION "4.2.7p440" /** Full ntpd version text */ -#define NTPD_FULL_VERSION "ntpd 4.2.7p439" +#define NTPD_FULL_VERSION "ntpd 4.2.7p440" /** * Interface defines for all options. Replace "n" with the UPPER_CASED diff --git a/ntpd/ntpd.1ntpdman b/ntpd/ntpd.1ntpdman index 525403a60..daa4e2541 100644 --- a/ntpd/ntpd.1ntpdman +++ b/ntpd/ntpd.1ntpdman @@ -10,11 +10,11 @@ .ds B-Font B .ds I-Font I .ds R-Font R -.TH ntpd 1ntpdman "02 Apr 2014" "4.2.7p439" "User Commands" +.TH ntpd 1ntpdman "09 Apr 2014" "4.2.7p440" "User Commands" .\" -.\" EDIT THIS FILE WITH CAUTION (/tmp/.ag-pRaaO0/ag-ERaaN0) +.\" EDIT THIS FILE WITH CAUTION (/tmp/.ag-Xaa4Hh/ag-8aa4Gh) .\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:27 AM by AutoGen 5.18.3pre18 +.\" It has been AutoGen-ed April 9, 2014 at 10:03:29 AM by AutoGen 5.18.3pre18 .\" From the definitions ntpd-opts.def .\" and the template file agman-cmd.tpl .SH NAME @@ -434,11 +434,11 @@ by loading values from environment variables named: \fBNTPD_\fP or \fBNTPD\fP .fi .ad -.TH ntpd 1ntpdman "02 Apr 2014" "4.2.7p439" "User Commands" +.TH ntpd 1ntpdman "09 Apr 2014" "4.2.7p440" "User Commands" .\" -.\" EDIT THIS FILE WITH CAUTION (/tmp/.ag-pRaaO0/ag-ERaaN0) +.\" EDIT THIS FILE WITH CAUTION (/tmp/.ag-Xaa4Hh/ag-8aa4Gh) .\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:27 AM by AutoGen 5.18.3pre18 +.\" It has been AutoGen-ed April 9, 2014 at 10:03:29 AM by AutoGen 5.18.3pre18 .\" From the definitions ntpd-opts.def .\" and the template file agman-cmd.tpl .SH NAME diff --git a/ntpd/ntpd.1ntpdmdoc b/ntpd/ntpd.1ntpdmdoc index 6c938ae35..3d9415865 100644 --- a/ntpd/ntpd.1ntpdmdoc +++ b/ntpd/ntpd.1ntpdmdoc @@ -1,9 +1,9 @@ -.Dd April 2 2014 +.Dd April 9 2014 .Dt NTPD 1ntpdmdoc User Commands .Os .\" EDIT THIS FILE WITH CAUTION (ntpd-opts.mdoc) .\" -.\" It has been AutoGen-ed April 2, 2014 at 10:47:50 AM by AutoGen 5.18.3pre18 +.\" It has been AutoGen-ed April 9, 2014 at 10:03:51 AM by AutoGen 5.18.3pre18 .\" From the definitions ntpd-opts.def .\" and the template file agmdoc-cmd.tpl .Sh NAME diff --git a/ntpd/ntpd.html b/ntpd/ntpd.html index 22a0deec3..6ce332c92 100644 --- a/ntpd/ntpd.html +++ b/ntpd/ntpd.html @@ -39,7 +39,7 @@ The program can operate in any of several modes, including client/server, symmetric and broadcast modes, and with both symmetric-key and public-key cryptography. -

This document applies to version 4.2.7p439 of ntpd. +

This document applies to version 4.2.7p440 of ntpd.