man/journald.conf.xml

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  23
  24 <refentry id="journald.conf"
  25     xmlns:xi="http://www.w3.org/2001/XInclude">
  26   <refentryinfo>
  27     <title>journald.conf</title>
  28     <productname>systemd</productname>
  29
  30     <authorgroup>
  31       <author>
  32         <contrib>Developer</contrib>
  33         <firstname>Lennart</firstname>
  34         <surname>Poettering</surname>
  35         <email>lennart@poettering.net</email>
  36       </author>
  37     </authorgroup>
  38   </refentryinfo>
  39
  40   <refmeta>
  41     <refentrytitle>journald.conf</refentrytitle>
  42     <manvolnum>5</manvolnum>
  43   </refmeta>
  44
  45   <refnamediv>
  46     <refname>journald.conf</refname>
  47     <refname>journald.conf.d</refname>
  48     <refpurpose>Journal service configuration files</refpurpose>
  49   </refnamediv>
  50
  51   <refsynopsisdiv>
  52     <para><filename>/etc/systemd/journald.conf</filename></para>
  53     <para><filename>/etc/systemd/journald.conf.d/*.conf</filename></para>
  54     <para><filename>/run/systemd/journald.conf.d/*.conf</filename></para>
  55     <para><filename>/usr/lib/systemd/journald.conf.d/*.conf</filename></para>
  56   </refsynopsisdiv>
  57
  58   <refsect1>
  59     <title>Description</title>
  60
  61     <para>These files configure various parameters of the systemd
  62     journal service,
  63     <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
  64
  65   </refsect1>
  66
  67   <xi:include href="standard-conf.xml" xpointer="confd" />
  68   <xi:include href="standard-conf.xml" xpointer="conf" />
  69
  70   <refsect1>
  71     <title>Options</title>
  72
  73     <para>All options are configured in the
  74     <literal>[Journal]</literal> section:</para>
  75
  76     <variablelist>
  77
  78       <varlistentry>
  79         <term><varname>Storage=</varname></term>
  80
  81         <listitem><para>Controls where to store journal data. One of
  82         <literal>volatile</literal>,
  83         <literal>persistent</literal>,
  84         <literal>auto</literal> and
  85         <literal>none</literal>. If
  86         <literal>volatile</literal>, journal
  87         log data will be stored only in memory, i.e. below the
  88         <filename>/run/log/journal</filename> hierarchy (which is
  89         created if needed). If <literal>persistent</literal>, data
  90         will be stored preferably on disk, i.e. below the
  91         <filename>/var/log/journal</filename> hierarchy (which is
  92         created if needed), with a fallback to
  93         <filename>/run/log/journal</filename> (which is created if
  94         needed), during early boot and if the disk is not writable.
  95         <literal>auto</literal> is similar to
  96         <literal>persistent</literal> but the directory
  97         <filename>/var/log/journal</filename> is not created if
  98         needed, so that its existence controls where log data goes.
  99         <literal>none</literal> turns off all storage, all log data
 100         received will be dropped. Forwarding to other targets, such as
 101         the console, the kernel log buffer or a syslog daemon will
 102         still work however. Defaults to
 103         <literal>auto</literal>.</para></listitem>
 104       </varlistentry>
 105
 106       <varlistentry>
 107         <term><varname>Compress=</varname></term>
 108
 109         <listitem><para>Takes a boolean value. If enabled (the
 110         default), data objects that shall be stored in the journal and
 111         are larger than a certain threshold are compressed before they
 112         are written to the file system.</para></listitem>
 113       </varlistentry>
 114
 115       <varlistentry>
 116         <term><varname>Seal=</varname></term>
 117
 118         <listitem><para>Takes a boolean value. If enabled (the
 119         default), and a sealing key is available (as created by
 120         <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
 121         <option>--setup-keys</option> command), Forward Secure Sealing
 122         (FSS) for all persistent journal files is enabled. FSS is
 123         based on <ulink
 124         url="https://eprint.iacr.org/2013/397">Seekable Sequential Key
 125         Generators</ulink> by G. A. Marson and B. Poettering
 126         (doi:10.1007/978-3-642-40203-6_7) and may be used to protect
 127         journal files from unnoticed alteration.</para></listitem>
 128       </varlistentry>
 129
 130       <varlistentry>
 131         <term><varname>SplitMode=</varname></term>
 132
 133         <listitem><para>Controls whether to split up journal files per
 134         user. One of <literal>uid</literal>, <literal>login</literal>
 135         and <literal>none</literal>. If <literal>uid</literal>, all
 136         users will get each their own journal files regardless of
 137         whether they possess a login session or not, however system
 138         users will log into the system journal. If
 139         <literal>login</literal>, actually logged-in users will get
 140         each their own journal files, but users without login session
 141         and system users will log into the system journal. If
 142         <literal>none</literal>, journal files are not split up by
 143         user and all messages are instead stored in the single system
 144         journal. Note that splitting up journal files by user is only
 145         available for journals stored persistently. If journals are
 146         stored on volatile storage (see above), only a single journal
 147         file for all user IDs is kept. Defaults to
 148         <literal>uid</literal>.</para></listitem>
 149       </varlistentry>
 150
 151       <varlistentry>
 152         <term><varname>RateLimitInterval=</varname></term>
 153         <term><varname>RateLimitBurst=</varname></term>
 154
 155         <listitem><para>Configures the rate limiting that is applied
 156         to all messages generated on the system. If, in the time
 157         interval defined by <varname>RateLimitInterval=</varname>,
 158         more messages than specified in
 159         <varname>RateLimitBurst=</varname> are logged by a service,
 160         all further messages within the interval are dropped until the
 161         interval is over. A message about the number of dropped
 162         messages is generated. This rate limiting is applied
 163         per-service, so that two services which log do not interfere
 164         with each other's limits. Defaults to 1000 messages in 30s.
 165         The time specification for
 166         <varname>RateLimitInterval=</varname> may be specified in the
 167         following units: <literal>s</literal>, <literal>min</literal>,
 168         <literal>h</literal>, <literal>ms</literal>,
 169         <literal>us</literal>. To turn off any kind of rate limiting,
 170         set either value to 0.</para></listitem>
 171       </varlistentry>
 172
 173       <varlistentry>
 174         <term><varname>SystemMaxUse=</varname></term>
 175         <term><varname>SystemKeepFree=</varname></term>
 176         <term><varname>SystemMaxFileSize=</varname></term>
 177         <term><varname>RuntimeMaxUse=</varname></term>
 178         <term><varname>RuntimeKeepFree=</varname></term>
 179         <term><varname>RuntimeMaxFileSize=</varname></term>
 180
 181         <listitem><para>Enforce size limits on the journal files
 182         stored. The options prefixed with <literal>System</literal>
 183         apply to the journal files when stored on a persistent file
 184         system, more specifically
 185         <filename>/var/log/journal</filename>. The options prefixed
 186         with <literal>Runtime</literal> apply to the journal files
 187         when stored on a volatile in-memory file system, more
 188         specifically <filename>/run/log/journal</filename>. The former
 189         is used only when <filename>/var</filename> is mounted,
 190         writable, and the directory
 191         <filename>/var/log/journal</filename> exists. Otherwise, only
 192         the latter applies. Note that this means that during early
 193         boot and if the administrator disabled persistent logging,
 194         only the latter options apply, while the former apply if
 195         persistent logging is enabled and the system is fully booted
 196         up. <command>journalctl</command> and
 197         <command>systemd-journald</command> ignore all files with
 198         names not ending with <literal>.journal</literal> or
 199         <literal>.journal~</literal>, so only such files, located in
 200         the appropriate directories, are taken into account when
 201         calculating current disk usage.
 202         </para>
 203
 204         <para><varname>SystemMaxUse=</varname> and
 205         <varname>RuntimeMaxUse=</varname> control how much disk space
 206         the journal may use up at maximum.
 207         <varname>SystemKeepFree=</varname> and
 208         <varname>RuntimeKeepFree=</varname> control how much disk
 209         space systemd-journald shall leave free for other uses.
 210         <command>systemd-journald</command> will respect both limits
 211         and use the smaller of the two values.</para>
 212
 213         <para>The first pair defaults to 10% and the second to 15% of
 214         the size of the respective file system. If the file system is
 215         nearly full and either <varname>SystemKeepFree=</varname> or
 216         <varname>RuntimeKeepFree=</varname> is violated when
 217         systemd-journald is started, the value will be raised to
 218         percentage that is actually free. This means that if there was
 219         enough free space before and journal files were created, and
 220         subsequently something else causes the file system to fill up,
 221         journald will stop using more space, but it will not be
 222         removing existing files to go reduce footprint either.</para>
 223
 224         <para><varname>SystemMaxFileSize=</varname>
 225         and
 226         <varname>RuntimeMaxFileSize=</varname>
 227         control how large individual journal
 228         files may grow at maximum. This
 229         influences the granularity in which
 230         disk space is made available through
 231         rotation, i.e. deletion of historic
 232         data. Defaults to one eighth of the
 233         values configured with
 234         <varname>SystemMaxUse=</varname> and
 235         <varname>RuntimeMaxUse=</varname>, so
 236         that usually seven rotated journal
 237         files are kept as history. Specify
 238         values in bytes or use K, M, G, T, P,
 239         E as units for the specified sizes
 240         (equal to 1024, 1024²,... bytes).
 241         Note that size limits are enforced
 242         synchronously when journal files are
 243         extended, and no explicit rotation
 244         step triggered by time is
 245         needed.</para></listitem>
 246       </varlistentry>
 247
 248       <varlistentry>
 249         <term><varname>MaxFileSec=</varname></term>
 250
 251         <listitem><para>The maximum time to store entries in a single
 252         journal file before rotating to the next one. Normally,
 253         time-based rotation should not be required as size-based
 254         rotation with options such as
 255         <varname>SystemMaxFileSize=</varname> should be sufficient to
 256         ensure that journal files do not grow without bounds. However,
 257         to ensure that not too much data is lost at once when old
 258         journal files are deleted, it might make sense to change this
 259         value from the default of one month. Set to 0 to turn off this
 260         feature. This setting takes time values which may be suffixed
 261         with the units <literal>year</literal>,
 262         <literal>month</literal>, <literal>week</literal>,
 263         <literal>day</literal>, <literal>h</literal> or
 264         <literal>m</literal> to override the default time unit of
 265         seconds.</para></listitem>
 266       </varlistentry>
 267
 268       <varlistentry>
 269         <term><varname>MaxRetentionSec=</varname></term>
 270
 271         <listitem><para>The maximum time to store journal entries.
 272         This controls whether journal files containing entries older
 273         then the specified time span are deleted. Normally, time-based
 274         deletion of old journal files should not be required as
 275         size-based deletion with options such as
 276         <varname>SystemMaxUse=</varname> should be sufficient to
 277         ensure that journal files do not grow without bounds. However,
 278         to enforce data retention policies, it might make sense to
 279         change this value from the default of 0 (which turns off this
 280         feature). This setting also takes time values which may be
 281         suffixed with the units <literal>year</literal>,
 282         <literal>month</literal>, <literal>week</literal>,
 283         <literal>day</literal>, <literal>h</literal> or <literal>
 284         m</literal> to override the default time unit of
 285         seconds.</para></listitem>
 286       </varlistentry>
 287
 288
 289       <varlistentry>
 290         <term><varname>SyncIntervalSec=</varname></term>
 291
 292         <listitem><para>The timeout before synchronizing journal files
 293         to disk. After syncing, journal files are placed in the
 294         OFFLINE state. Note that syncing is unconditionally done
 295         immediately after a log message of priority CRIT, ALERT or
 296         EMERG has been logged. This setting hence applies only to
 297         messages of the levels ERR, WARNING, NOTICE, INFO, DEBUG. The
 298         default timeout is 5 minutes. </para></listitem>
 299       </varlistentry>
 300
 301       <varlistentry>
 302         <term><varname>ForwardToSyslog=</varname></term>
 303         <term><varname>ForwardToKMsg=</varname></term>
 304         <term><varname>ForwardToConsole=</varname></term>
 305         <term><varname>ForwardToWall=</varname></term>
 306
 307         <listitem><para>Control whether log messages received by the
 308         journal daemon shall be forwarded to a traditional syslog
 309         daemon, to the kernel log buffer (kmsg), to the system
 310         console, or sent as wall messages to all logged-in users.
 311         These options take boolean arguments. If forwarding to syslog
 312         is enabled but no syslog daemon is running, the respective
 313         option has no effect. By default, only forwarding wall is
 314         enabled. These settings may be overridden at boot time with
 315         the kernel command line options
 316         <literal>systemd.journald.forward_to_syslog=</literal>,
 317         <literal>systemd.journald.forward_to_kmsg=</literal>,
 318         <literal>systemd.journald.forward_to_console=</literal> and
 319         <literal>systemd.journald.forward_to_wall=</literal>. When
 320         forwarding to the console, the TTY to log to can be changed
 321         with <varname>TTYPath=</varname>, described
 322         below.</para></listitem>
 323       </varlistentry>
 324
 325       <varlistentry>
 326         <term><varname>MaxLevelStore=</varname></term>
 327         <term><varname>MaxLevelSyslog=</varname></term>
 328         <term><varname>MaxLevelKMsg=</varname></term>
 329         <term><varname>MaxLevelConsole=</varname></term>
 330         <term><varname>MaxLevelWall=</varname></term>
 331
 332         <listitem><para>Controls the maximum log level of messages
 333         that are stored on disk, forwarded to syslog, kmsg, the
 334         console or wall (if that is enabled, see above). As argument,
 335         takes one of
 336         <literal>emerg</literal>,
 337         <literal>alert</literal>,
 338         <literal>crit</literal>,
 339         <literal>err</literal>,
 340         <literal>warning</literal>,
 341         <literal>notice</literal>,
 342         <literal>info</literal>,
 343         <literal>debug</literal>,
 344         or integer values in the range of 0..7 (corresponding to the
 345         same levels). Messages equal or below the log level specified
 346         are stored/forwarded, messages above are dropped. Defaults to
 347         <literal>debug</literal> for <varname>MaxLevelStore=</varname>
 348         and <varname>MaxLevelSyslog=</varname>, to ensure that the all
 349         messages are written to disk and forwarded to syslog. Defaults
 350         to
 351         <literal>notice</literal> for <varname>MaxLevelKMsg=</varname>,
 352         <literal>info</literal> for <varname>MaxLevelConsole=</varname>,
 353         and <literal>emerg</literal> for
 354         <varname>MaxLevelWall=</varname>.</para></listitem>
 355       </varlistentry>
 356
 357       <varlistentry>
 358         <term><varname>TTYPath=</varname></term>
 359
 360         <listitem><para>Change the console TTY to use if
 361         <varname>ForwardToConsole=yes</varname> is used. Defaults to
 362         <filename>/dev/console</filename>.</para></listitem>
 363       </varlistentry>
 364
 365     </variablelist>
 366
 367   </refsect1>
 368
 369   <refsect1>
 370       <title>See Also</title>
 371       <para>
 372         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 373         <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 374         <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 375         <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 376         <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 377       </para>
 378   </refsect1>
 379
 380 </refentry>