1 <?xml version='
1.0'
?> <!--*-nxml-*-->
2 <!DOCTYPE refentry PUBLIC
"-//OASIS//DTD DocBook XML V4.2//EN"
3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
6 This file is part of systemd.
8 Copyright 2013 Tom Gundersen
10 systemd is free software; you can redistribute it and/or modify it
11 under the terms of the GNU Lesser General Public License as published by
12 the Free Software Foundation; either version 2.1 of the License, or
13 (at your option) any later version.
15 systemd is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
20 You should have received a copy of the GNU Lesser General Public License
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 <refentry id=
"systemd.netdev" conditional='ENABLE_NETWORKD'
>
27 <title>systemd.network
</title>
28 <productname>systemd
</productname>
32 <contrib>Developer
</contrib>
33 <firstname>Tom
</firstname>
34 <surname>Gundersen
</surname>
35 <email>teg@jklm.no
</email>
41 <refentrytitle>systemd.netdev
</refentrytitle>
42 <manvolnum>5</manvolnum>
46 <refname>systemd.netdev
</refname>
47 <refpurpose>Virtual Network Device configuration
</refpurpose>
51 <para><filename><replaceable>netdev
</replaceable>.netdev
</filename></para>
55 <title>Description
</title>
57 <para>Network setup is performed by
58 <citerefentry><refentrytitle>systemd-networkd
</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
61 <para>Virtual Network Device files must have the extension
62 <filename>.netdev
</filename>; other extensions are ignored.
63 Virtual network devices are created as soon as networkd is
64 started. If a netdev with the specified name already exists,
65 networkd will use that as-is rather than create its own. Note that
66 the settings of the pre-existing netdev will not be changed by
69 <para>The
<filename>.netdev
</filename> files are read from the
70 files located in the system network directory
71 <filename>/usr/lib/systemd/network
</filename>, the volatile
72 runtime network directory
73 <filename>/run/systemd/network
</filename> and the local
74 administration network directory
75 <filename>/etc/systemd/network
</filename>. All configuration files
76 are collectively sorted and processed in lexical order, regardless
77 of the directories in which they live. However, files with
78 identical filenames replace each other. Files in
79 <filename>/etc
</filename> have the highest priority, files in
80 <filename>/run
</filename> take precedence over files with the same
81 name in
<filename>/usr/lib
</filename>. This can be used to
82 override a system-supplied configuration file with a local file if
83 needed. As a special case, an empty file (file size
0) or symlink
84 with the same name pointing to
<filename>/dev/null
</filename>
85 disables the configuration file entirely (it is
"masked").
</para>
89 <title>Supported netdev kinds
</title>
91 <para>The following kinds of virtual network devices may be
92 configured in
<filename>.netdev
</filename> files:
</para>
95 <title>Supported kinds of virtual network devices
</title>
98 <colspec colname='kind'
/>
99 <colspec colname='explanation'
/>
102 <entry>Description
</entry>
105 <row><entry><varname>bond
</varname></entry>
106 <entry>A bond device is an aggregation of all its slave devices. See
<ulink url=
"https://www.kernel.org/doc/Documentation/networking/bonding.txt">Linux Ethernet Bonding Driver HOWTO
</ulink> for details.Local configuration
</entry></row>
108 <row><entry><varname>bridge
</varname></entry>
109 <entry>A bridge device is a software switch, and each of its slave devices and the bridge itself are ports of the switch.
</entry></row>
111 <row><entry><varname>dummy
</varname></entry>
112 <entry>A dummy device drops all packets sent to it.
</entry></row>
114 <row><entry><varname>gre
</varname></entry>
115 <entry>A Level
3 GRE tunnel over IPv4. See
<ulink url=
"https://tools.ietf.org/html/rfc2784">RFC
2784</ulink> for details.
</entry></row>
117 <row><entry><varname>gretap
</varname></entry>
118 <entry>A Level
2 GRE tunnel over IPv4.
</entry></row>
120 <row><entry><varname>ip6gre
</varname></entry>
121 <entry>A Level
3 GRE tunnel over IPv6.
</entry></row>
123 <row><entry><varname>ip6tnl
</varname></entry>
124 <entry>An IPv4 or IPv6 tunnel over IPv6
</entry></row>
126 <row><entry><varname>ip6gretap
</varname></entry>
127 <entry>An Level
2 GRE tunnel over IPv6.
</entry></row>
129 <row><entry><varname>ipip
</varname></entry>
130 <entry>An IPv4 over IPv4 tunnel.
</entry></row>
132 <row><entry><varname>ipvlan
</varname></entry>
133 <entry>An ipvlan device is a stacked device which receives packets from its underlying device based on IP address filtering.
</entry></row>
135 <row><entry><varname>macvlan
</varname></entry>
136 <entry>A macvlan device is a stacked device which receives packets from its underlying device based on MAC address filtering.
</entry></row>
138 <row><entry><varname>macvtap
</varname></entry>
139 <entry>A macvtap device is a stacked device which receives packets from its underlying device based on MAC address filtering.
</entry></row>
141 <row><entry><varname>sit
</varname></entry>
142 <entry>An IPv6 over IPv4 tunnel.
</entry></row>
144 <row><entry><varname>tap
</varname></entry>
145 <entry>A persistent Level
2 tunnel between a network device and a device node.
</entry></row>
147 <row><entry><varname>tun
</varname></entry>
148 <entry>A persistent Level
3 tunnel between a network device and a device node.
</entry></row>
150 <row><entry><varname>veth
</varname></entry>
151 <entry>An Ethernet tunnel between a pair of network devices.
</entry></row>
153 <row><entry><varname>vlan
</varname></entry>
154 <entry>A VLAN is a stacked device which receives packets from its underlying device based on VLAN tagging. See
<ulink url=
"http://www.ieee802.org/1/pages/802.1Q.html">IEEE
802.1Q
</ulink> for details.
</entry></row>
156 <row><entry><varname>vti
</varname></entry>
157 <entry>An IPv4 over IPSec tunnel.
</entry></row>
159 <row><entry><varname>vti6
</varname></entry>
160 <entry>An IPv6 over IPSec tunnel.
</entry></row>
162 <row><entry><varname>vxlan
</varname></entry>
163 <entry>A virtual extensible LAN (vxlan), for connecting Cloud computing deployments.
</entry></row>
165 <row><entry><varname>vrf
</varname></entry>
166 <entry>A Virtual Routing and Forwarding (
<ulink url=
"https://www.kernel.org/doc/Documentation/networking/vrf.txt">VRF
</ulink>) interface to create seperate routing and forwarding domains.
</entry></row>
175 <title>[Match] Section Options
</title>
177 <para>A virtual network device is only created if the
178 <literal>[Match]
</literal> section matches the current
179 environment, or if the section is empty. The following keys are
182 <variablelist class='network-directives'
>
184 <term><varname>Host=
</varname></term>
186 <para>Matches against the hostname or machine ID of the
187 host. See
<literal>ConditionHost=
</literal> in
188 <citerefentry><refentrytitle>systemd.unit
</refentrytitle><manvolnum>5</manvolnum></citerefentry>
194 <term><varname>Virtualization=
</varname></term>
196 <para>Checks whether the system is executed in a virtualized
197 environment and optionally test whether it is a specific
199 <literal>ConditionVirtualization=
</literal> in
200 <citerefentry><refentrytitle>systemd.unit
</refentrytitle><manvolnum>5</manvolnum></citerefentry>
206 <term><varname>KernelCommandLine=
</varname></term>
208 <para>Checks whether a specific kernel command line option
209 is set (or if prefixed with the exclamation mark unset). See
210 <literal>ConditionKernelCommandLine=
</literal> in
211 <citerefentry><refentrytitle>systemd.unit
</refentrytitle><manvolnum>5</manvolnum></citerefentry>
217 <term><varname>Architecture=
</varname></term>
219 <para>Checks whether the system is running on a specific
220 architecture. See
<literal>ConditionArchitecture=
</literal> in
221 <citerefentry><refentrytitle>systemd.unit
</refentrytitle><manvolnum>5</manvolnum></citerefentry>
231 <title>[NetDev] Section Options
</title>
233 <para>The
<literal>[NetDev]
</literal> section accepts the
234 following keys:
</para>
236 <variablelist class='network-directives'
>
238 <term><varname>Description=
</varname></term>
240 <para>A free-form description of the netdev.
</para>
244 <term><varname>Name=
</varname></term>
246 <para>The interface name used when creating the netdev.
247 This option is compulsory.
</para>
251 <term><varname>Kind=
</varname></term>
253 <para>The netdev kind. This option is compulsory. See the
254 <literal>Supported netdev kinds
</literal> section for the
259 <term><varname>MTUBytes=
</varname></term>
261 <para>The maximum transmission unit in bytes to set for
262 the device. The usual suffixes K, M, G, are supported and
263 are understood to the base of
1024. This key is not
264 currently supported for
<literal>tun
</literal> or
265 <literal>tap
</literal> devices.
270 <term><varname>MACAddress=
</varname></term>
272 <para>The MAC address to use for the device. If none is
273 given, one is generated based on the interface name and
275 <citerefentry><refentrytitle>machine-id
</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
276 This key is not currently supported for
277 <literal>tun
</literal> or
<literal>tap
</literal> devices.
285 <title>[Bridge] Section Options
</title>
287 <para>The
<literal>[Bridge]
</literal> section only applies for
288 netdevs of kind
<literal>bridge
</literal>, and accepts the
289 following keys:
</para>
291 <variablelist class='network-directives'
>
293 <term><varname>HelloTimeSec=
</varname></term>
295 <para>HelloTimeSec specifies the number of seconds between two hello packets
296 sent out by the root bridge and the designated bridges. Hello packets are
297 used to communicate information about the topology throughout the entire
298 bridged local area network.
</para>
302 <term><varname>MaxAgeSec=
</varname></term>
304 <para>MaxAgeSec specifies the number of seconds of maximum message age.
305 If the last seen (received) hello packet is more than this number of
306 seconds old, the bridge in question will start the takeover procedure
307 in attempt to become the Root Bridge itself.
</para>
311 <term><varname>ForwardDelaySec=
</varname></term>
313 <para>ForwardDelaySec specifies the number of seconds spent in each
314 of the Listening and Learning states before the Forwarding state is entered.
</para>
318 <term><varname>MulticastQuerier=
</varname></term>
320 <para>A boolean. This setting controls the IFLA_BR_MCAST_QUERIER option in the kernel.
321 If enabled, the kernel will send general ICMP queries from a zero source address.
322 This feature should allow faster convergence on startup, but it causes some
323 multicast-aware switches to misbehave and disrupt forwarding of multicast packets.
324 When unset, the kernel's default setting applies.
329 <term><varname>MulticastSnooping=
</varname></term>
331 <para>A boolean. This setting controls the IFLA_BR_MCAST_SNOOPING option in the kernel.
332 If enabled, IGMP snooping monitors the Internet Group Management Protocol (IGMP) traffic
333 between hosts and multicast routers. When unset, the kernel's default setting applies.
338 <term><varname>VLANFiltering=
</varname></term>
340 <para>A boolean. This setting controls the IFLA_BR_VLAN_FILTERING option in the kernel.
341 If enabled, the bridge will be started in VLAN-filtering mode. When unset, the kernel's
342 default setting applies.
351 <title>[VLAN] Section Options
</title>
353 <para>The
<literal>[VLAN]
</literal> section only applies for
354 netdevs of kind
<literal>vlan
</literal>, and accepts the
355 following key:
</para>
357 <variablelist class='network-directives'
>
359 <term><varname>Id=
</varname></term>
361 <para>The VLAN ID to use. An integer in the range
0–
4094.
362 This option is compulsory.
</para>
370 <title>[MACVLAN] Section Options
</title>
372 <para>The
<literal>[MACVLAN]
</literal> section only applies for
373 netdevs of kind
<literal>macvlan
</literal>, and accepts the
374 following key:
</para>
376 <variablelist class='network-directives'
>
378 <term><varname>Mode=
</varname></term>
380 <para>The MACVLAN mode to use. The supported options are
381 <literal>private
</literal>,
382 <literal>vepa
</literal>,
383 <literal>bridge
</literal>, and
384 <literal>passthru
</literal>.
393 <title>[MACVTAP] Section Options
</title>
395 <para>The
<literal>[MACVTAP]
</literal> section applies for
396 netdevs of kind
<literal>macvtap
</literal> and accepts the
397 same key as
<literal>[MACVLAN]
</literal>.
</para>
402 <title>[IPVLAN] Section Options
</title>
404 <para>The
<literal>[IPVLAN]
</literal> section only applies for
405 netdevs of kind
<literal>ipvlan
</literal>, and accepts the
406 following key:
</para>
408 <variablelist class='network-directives'
>
410 <term><varname>Mode=
</varname></term>
412 <para>The IPVLAN mode to use. The supported options are
413 <literal>L2
</literal> and
<literal>L3
</literal>.
422 <title>[VXLAN] Section Options
</title>
423 <para>The
<literal>[VXLAN]
</literal> section only applies for
424 netdevs of kind
<literal>vxlan
</literal>, and accepts the
425 following keys:
</para>
427 <variablelist class='network-directives'
>
429 <term><varname>Id=
</varname></term>
431 <para>The VXLAN ID to use.
</para>
435 <term><varname>Group=
</varname></term>
437 <para>An assigned multicast group IP address.
</para>
441 <term><varname>TOS=
</varname></term>
443 <para>The Type Of Service byte value for a vxlan interface.
</para>
447 <term><varname>TTL=
</varname></term>
449 <para>A fixed Time To Live N on Virtual eXtensible Local
450 Area Network packets. N is a number in the range
1–
255.
0
451 is a special value meaning that packets inherit the TTL
456 <term><varname>MacLearning=
</varname></term>
458 <para>A boolean. When true, enables dynamic MAC learning
459 to discover remote MAC addresses.
</para>
463 <term><varname>FDBAgeingSec=
</varname></term>
465 <para>The lifetime of Forwarding Database entry learnt by
466 the kernel, in seconds.
</para>
470 <term><varname>MaximumFDBEntries=
</varname></term>
472 <para>Configures maximum number of FDB entries.
</para>
476 <term><varname>ARPProxy=
</varname></term>
478 <para>A boolean. When true, enables ARP proxying.
</para>
482 <term><varname>L2MissNotification=
</varname></term>
484 <para>A boolean. When true, enables netlink LLADDR miss
485 notifications.
</para>
489 <term><varname>L3MissNotification=
</varname></term>
491 <para>A boolean. When true, enables netlink IP address miss
492 notifications.
</para>
496 <term><varname>RouteShortCircuit=
</varname></term>
498 <para>A boolean. When true, route short circuiting is turned
503 <term><varname>UDPCheckSum=
</varname></term>
505 <para>A boolean. When true, transmitting UDP checksums when doing VXLAN/IPv4 is turned on.
</para>
509 <term><varname>UDP6ZeroChecksumTx=
</varname></term>
511 <para>A boolean. When true, sending zero checksums in VXLAN/IPv6 is turned on.
</para>
515 <term><varname>UDP6ZeroCheckSumRx=
</varname></term>
517 <para>A boolean. When true, receiving zero checksums in VXLAN/IPv6 is turned on.
</para>
521 <term><varname>GroupPolicyExtension=
</varname></term>
523 <para>A boolean. When true, it enables Group Policy VXLAN extension security label mechanism
524 across network peers based on VXLAN. For details about the Group Policy VXLAN, see the
525 <ulink url=
"https://tools.ietf.org/html/draft-smith-vxlan-group-policy">
526 VXLAN Group Policy
</ulink> document. Defaults to false.
</para>
530 <term><varname>DestinationPort=
</varname></term>
532 <para>Configures the default destination UDP port on a per-device basis.
533 If destination port is not specified then Linux kernel default will be used.
534 Set destination port
4789 to get the IANA assigned value,
535 and destination port
0 to get default values.
</para>
539 <term><varname>PortRange=
</varname></term>
541 <para>Configures VXLAN port range. VXLAN bases source
542 UDP port based on flow to help the receiver to be able
543 to load balance based on outer header flow. It
544 restricts the port range to the normal UDP local
545 ports, and allows overriding via configuration.
</para>
551 <title>[Tunnel] Section Options
</title>
553 <para>The
<literal>[Tunnel]
</literal> section only applies for
555 <literal>ipip
</literal>,
556 <literal>sit
</literal>,
557 <literal>gre
</literal>,
558 <literal>gretap
</literal>,
559 <literal>ip6gre
</literal>,
560 <literal>ip6gretap
</literal>,
561 <literal>vti
</literal>,
562 <literal>vti6
</literal>, and
563 <literal>ip6tnl
</literal> and accepts
564 the following keys:
</para>
566 <variablelist class='network-directives'
>
568 <term><varname>Local=
</varname></term>
570 <para>A static local address for tunneled packets. It must
571 be an address on another interface of this host.
</para>
575 <term><varname>Remote=
</varname></term>
577 <para>The remote endpoint of the tunnel.
</para>
581 <term><varname>TOS=
</varname></term>
583 <para>The Type Of Service byte value for a tunnel interface.
584 For details about the TOS, see the
585 <ulink url=
"http://tools.ietf.org/html/rfc1349"> Type of
586 Service in the Internet Protocol Suite
</ulink> document.
591 <term><varname>TTL=
</varname></term>
593 <para>A fixed Time To Live N on tunneled packets. N is a
594 number in the range
1–
255.
0 is a special value meaning that
595 packets inherit the TTL value. The default value for IPv4
596 tunnels is: inherit. The default value for IPv6 tunnels is
601 <term><varname>DiscoverPathMTU=
</varname></term>
603 <para>A boolean. When true, enables Path MTU Discovery on
608 <term><varname>IPv6FlowLabel=
</varname></term>
610 <para>Configures the
20-bit flow label (see
<ulink url=
"https://tools.ietf.org/html/rfc6437">
611 RFC
6437</ulink>) field in the IPv6 header (see
<ulink url=
"https://tools.ietf.org/html/rfc2460">
612 RFC
2460</ulink>), which is used by a node to label packets of a flow.
613 It is only used for IPv6 tunnels.
614 A flow label of zero is used to indicate packets that have
616 It can be configured to a value in the range
0–
0xFFFFF, or be
617 set to
<literal>inherit
</literal>, in which case the original flowlabel is used.
</para>
621 <term><varname>CopyDSCP=
</varname></term>
623 <para>A boolean. When true, the Differentiated Service Code
624 Point (DSCP) field will be copied to the inner header from
625 outer header during the decapsulation of an IPv6 tunnel
626 packet. DSCP is a field in an IP packet that enables different
627 levels of service to be assigned to network traffic.
628 Defaults to
<literal>no
</literal>.
633 <term><varname>EncapsulationLimit=
</varname></term>
635 <para>The Tunnel Encapsulation Limit option specifies how many additional
636 levels of encapsulation are permitted to be prepended to the packet.
637 For example, a Tunnel Encapsulation Limit option containing a limit
638 value of zero means that a packet carrying that option may not enter
639 another tunnel before exiting the current tunnel.
640 (see
<ulink url=
"https://tools.ietf.org/html/rfc2473#section-4.1.1"> RFC
2473</ulink>).
641 The valid range is
0–
255 and
<literal>none
</literal>. Defaults to
4.
646 <term><varname>Key=
</varname></term>
648 <para>The
<varname>Key=
</varname> parameter specifies the same key to use in
649 both directions (
<varname>InputKey=
</varname> and
<varname>OutputKey=
</varname>).
650 The
<varname>Key=
</varname> is either a number or an IPv4 address-like dotted quad.
651 It is used as mark-configured SAD/SPD entry as part of the lookup key (both in data
652 and control path) in ip xfrm (framework used to implement IPsec protocol).
653 See
<ulink url=
"http://man7.org/linux/man-pages/man8/ip-xfrm.8.html">
654 ip-xfrm - transform configuration
</ulink> for details. It is only used for VTI/VTI6
659 <term><varname>InputKey=
</varname></term>
661 <para>The
<varname>InputKey=
</varname> parameter specifies the key to use for input.
662 The format is same as
<varname>Key=
</varname>. It is only used for VTI/VTI6 tunnels.
</para>
666 <term><varname>OutputKey=
</varname></term>
668 <para>The
<varname>OutputKey=
</varname> parameter specifies the key to use for output.
669 The format is same as
<varname>Key=
</varname>. It is only used for VTI/VTI6 tunnels.
</para>
673 <term><varname>Mode=
</varname></term>
675 <para>An
<literal>ip6tnl
</literal> tunnel can be in one of three
677 <literal>ip6ip6
</literal> for IPv6 over IPv6,
678 <literal>ipip6
</literal> for IPv4 over IPv6 or
679 <literal>any
</literal> for either.
686 <title>[Peer] Section Options
</title>
688 <para>The
<literal>[Peer]
</literal> section only applies for
689 netdevs of kind
<literal>veth
</literal> and accepts the
690 following keys:
</para>
692 <variablelist class='network-directives'
>
694 <term><varname>Name=
</varname></term>
696 <para>The interface name used when creating the netdev.
697 This option is compulsory.
</para>
701 <term><varname>MACAddress=
</varname></term>
703 <para>The peer MACAddress, if not set, it is generated in
704 the same way as the MAC address of the main
711 <title>[Tun] Section Options
</title>
713 <para>The
<literal>[Tun]
</literal> section only applies for
714 netdevs of kind
<literal>tun
</literal>, and accepts the following
717 <variablelist class='network-directives'
>
719 <term><varname>OneQueue=
</varname></term>
720 <listitem><para>Takes a boolean argument. Configures whether
721 all packets are queued at the device (enabled), or a fixed
722 number of packets are queued at the device and the rest at the
723 <literal>qdisc
</literal>. Defaults to
724 <literal>no
</literal>.
</para>
728 <term><varname>MultiQueue=
</varname></term>
729 <listitem><para>Takes a boolean argument. Configures whether
730 to use multiple file descriptors (queues) to parallelize
731 packets sending and receiving. Defaults to
732 <literal>no
</literal>.
</para>
736 <term><varname>PacketInfo=
</varname></term>
737 <listitem><para>Takes a boolean argument. Configures whether
738 packets should be prepended with four extra bytes (two flag
739 bytes and two protocol bytes). If disabled, it indicates that
740 the packets will be pure IP packets. Defaults to
741 <literal>no
</literal>.
</para>
745 <term><varname>VNetHeader=
</varname></term>
746 <listitem><para>Takes a boolean argument. Configures
747 IFF_VNET_HDR flag for a tap device. It allows sending
748 and receiving larger Generic Segmentation Offload (GSO)
749 packets. This may increase throughput significantly.
751 <literal>no
</literal>.
</para>
755 <term><varname>User=
</varname></term>
756 <listitem><para>User to grant access to the
757 <filename>/dev/net/tun
</filename> device.
</para>
761 <term><varname>Group=
</varname></term>
762 <listitem><para>Group to grant access to the
763 <filename>/dev/net/tun
</filename> device.
</para>
772 <title>[Tap] Section Options
</title>
774 <para>The
<literal>[Tap]
</literal> section only applies for
775 netdevs of kind
<literal>tap
</literal>, and accepts the same keys
776 as the
<literal>[Tun]
</literal> section.
</para>
780 <title>[Bond] Section Options
</title>
782 <para>The
<literal>[Bond]
</literal> section accepts the following
785 <variablelist class='network-directives'
>
787 <term><varname>Mode=
</varname></term>
789 <para>Specifies one of the bonding policies. The default is
790 <literal>balance-rr
</literal> (round robin). Possible values are
791 <literal>balance-rr
</literal>,
792 <literal>active-backup
</literal>,
793 <literal>balance-xor
</literal>,
794 <literal>broadcast
</literal>,
795 <literal>802.3ad
</literal>,
796 <literal>balance-tlb
</literal>, and
797 <literal>balance-alb
</literal>.
803 <term><varname>TransmitHashPolicy=
</varname></term>
805 <para>Selects the transmit hash policy to use for slave
806 selection in balance-xor,
802.3ad, and tlb modes. Possible
808 <literal>layer2
</literal>,
809 <literal>layer3+
4</literal>,
810 <literal>layer2+
3</literal>,
811 <literal>encap2+
3</literal>,
812 <literal>802.3ad
</literal>, and
813 <literal>encap3+
4</literal>.
819 <term><varname>LACPTransmitRate=
</varname></term>
821 <para>Specifies the rate with which link partner transmits
822 Link Aggregation Control Protocol Data Unit packets in
823 802.3ad mode. Possible values are
<literal>slow
</literal>,
824 which requests partner to transmit LACPDUs every
30 seconds,
825 and
<literal>fast
</literal>, which requests partner to
826 transmit LACPDUs every second. The default value is
827 <literal>slow
</literal>.
</para>
832 <term><varname>MIIMonitorSec=
</varname></term>
834 <para>Specifies the frequency that Media Independent
835 Interface link monitoring will occur. A value of zero
836 disables MII link monitoring. This value is rounded down to
837 the nearest millisecond. The default value is
0.
</para>
842 <term><varname>UpDelaySec=
</varname></term>
844 <para>Specifies the delay before a link is enabled after a
845 link up status has been detected. This value is rounded down
846 to a multiple of MIIMonitorSec. The default value is
852 <term><varname>DownDelaySec=
</varname></term>
854 <para>Specifies the delay before a link is disabled after a
855 link down status has been detected. This value is rounded
856 down to a multiple of MIIMonitorSec. The default value is
862 <term><varname>LearnPacketIntervalSec=
</varname></term>
864 <para>Specifies the number of seconds between instances where the bonding
865 driver sends learning packets to each slave peer switch.
866 The valid range is
1–
0x7fffffff; the default value is
1. This option
867 has an effect only for the balance-tlb and balance-alb modes.
</para>
872 <term><varname>AdSelect=
</varname></term>
874 <para>Specifies the
802.3ad aggregation selection logic to use. Possible values are
875 <literal>stable
</literal>,
876 <literal>bandwidth
</literal> and
877 <literal>count
</literal>.
883 <term><varname>FailOverMACPolicy=
</varname></term>
885 <para>Specifies whether the active-backup mode should set all slaves to
886 the same MAC address at the time of enslavement or, when enabled, to perform special handling of the
887 bond's MAC address in accordance with the selected policy. The default policy is none.
889 <literal>none
</literal>,
890 <literal>active
</literal> and
891 <literal>follow
</literal>.
897 <term><varname>ARPValidate=
</varname></term>
899 <para>Specifies whether or not ARP probes and replies should be
900 validated in any mode that supports ARP monitoring, or whether
901 non-ARP traffic should be filtered (disregarded) for link
902 monitoring purposes. Possible values are
903 <literal>none
</literal>,
904 <literal>active
</literal>,
905 <literal>backup
</literal> and
906 <literal>all
</literal>.
912 <term><varname>ARPIntervalSec=
</varname></term>
914 <para>Specifies the ARP link monitoring frequency in milliseconds.
915 A value of
0 disables ARP monitoring. The default value is
0.
921 <term><varname>ARPIPTargets=
</varname></term>
923 <para>Specifies the IP addresses to use as ARP monitoring peers when
924 ARPIntervalSec is greater than
0. These are the targets of the ARP request
925 sent to determine the health of the link to the targets.
926 Specify these values in IPv4 dotted decimal format. At least one IP
927 address must be given for ARP monitoring to function. The
928 maximum number of targets that can be specified is
16. The
929 default value is no IP addresses.
935 <term><varname>ARPAllTargets=
</varname></term>
937 <para>Specifies the quantity of ARPIPTargets that must be reachable
938 in order for the ARP monitor to consider a slave as being up.
939 This option affects only active-backup mode for slaves with
940 ARPValidate enabled. Possible values are
941 <literal>any
</literal> and
942 <literal>all
</literal>.
948 <term><varname>PrimaryReselectPolicy=
</varname></term>
950 <para>Specifies the reselection policy for the primary slave. This
951 affects how the primary slave is chosen to become the active slave
952 when failure of the active slave or recovery of the primary slave
953 occurs. This option is designed to prevent flip-flopping between
954 the primary slave and other slaves. Possible values are
955 <literal>always
</literal>,
956 <literal>better
</literal> and
957 <literal>failure
</literal>.
963 <term><varname>ResendIGMP=
</varname></term>
965 <para>Specifies the number of IGMP membership reports to be issued after
966 a failover event. One membership report is issued immediately after
967 the failover, subsequent packets are sent in each
200ms interval.
968 The valid range is
0–
255. Defaults to
1. A value of
0
969 prevents the IGMP membership report from being issued in response
970 to the failover event.
976 <term><varname>PacketsPerSlave=
</varname></term>
978 <para>Specify the number of packets to transmit through a slave before
979 moving to the next one. When set to
0, then a slave is chosen at
980 random. The valid range is
0–
65535. Defaults to
1. This option
981 only has effect when in balance-rr mode.
987 <term><varname>GratuitousARP=
</varname></term>
989 <para>Specify the number of peer notifications (gratuitous ARPs and
990 unsolicited IPv6 Neighbor Advertisements) to be issued after a
991 failover event. As soon as the link is up on the new slave,
992 a peer notification is sent on the bonding device and each
993 VLAN sub-device. This is repeated at each link monitor interval
994 (ARPIntervalSec or MIIMonitorSec, whichever is active) if the number is
995 greater than
1. The valid range is
0–
255. The default value is
1.
996 These options affect only the active-backup mode.
1002 <term><varname>AllSlavesActive=
</varname></term>
1004 <para>A boolean. Specifies that duplicate frames (received on inactive ports)
1005 should be dropped when false, or delivered when true. Normally, bonding will drop
1006 duplicate frames (received on inactive ports), which is desirable for
1007 most users. But there are some times it is nice to allow duplicate
1008 frames to be delivered. The default value is false (drop duplicate frames
1009 received on inactive ports).
1015 <term><varname>MinLinks=
</varname></term>
1017 <para>Specifies the minimum number of links that must be active before
1018 asserting carrier. The default value is
0.
1025 <para>For more detail information see
1026 <ulink url=
"https://www.kernel.org/doc/Documentation/networking/bonding.txt">
1027 Linux Ethernet Bonding Driver HOWTO
</ulink></para>
1032 <title>Example
</title>
1034 <title>/etc/systemd/network/
25-bridge.netdev
</title>
1036 <programlisting>[NetDev]
1038 Kind=bridge
</programlisting>
1042 <title>/etc/systemd/network/
25-vlan1.netdev
</title>
1044 <programlisting>[Match]
1052 Id=
1</programlisting>
1055 <title>/etc/systemd/network/
25-ipip.netdev
</title>
1056 <programlisting>[NetDev]
1062 Local=
192.168.223.238
1063 Remote=
192.169.224.239
1064 TTL=
64</programlisting>
1067 <title>/etc/systemd/network/
25-tap.netdev
</title>
1068 <programlisting>[NetDev]
1074 PacketInfo=true
</programlisting> </example>
1077 <title>/etc/systemd/network/
25-sit.netdev
</title>
1078 <programlisting>[NetDev]
1085 Remote=
10.65.223.239</programlisting>
1089 <title>/etc/systemd/network/
25-gre.netdev
</title>
1090 <programlisting>[NetDev]
1097 Remote=
10.65.223.239</programlisting>
1101 <title>/etc/systemd/network/
25-vti.netdev
</title>
1103 <programlisting>[NetDev]
1110 Remote=
10.65.223.239</programlisting>
1114 <title>/etc/systemd/network/
25-veth.netdev
</title>
1115 <programlisting>[NetDev]
1120 Name=veth-peer
</programlisting>
1124 <title>/etc/systemd/network/
25-bond.netdev
</title>
1125 <programlisting>[NetDev]
1131 TransmitHashPolicy=layer3+
4
1133 LACPTransmitRate=fast
1138 <title>/etc/systemd/network/
25-dummy.netdev
</title>
1139 <programlisting>[NetDev]
1142 MACAddress=
12:
34:
56:
78:
9a:bc
</programlisting>
1145 <title>/etc/systemd/network/
25-vrf.netdev
</title>
1146 <para>Create an VRF interface with table
42.
</para>
1147 <programlisting>[NetDev]
1152 TableId=
42</programlisting>
1156 <title>See Also
</title>
1158 <citerefentry><refentrytitle>systemd
</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1159 <citerefentry><refentrytitle>systemd-networkd
</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
1160 <citerefentry><refentrytitle>systemd.link
</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1161 <citerefentry><refentrytitle>systemd.network
</refentrytitle><manvolnum>5</manvolnum></citerefentry>