SYSTEMD.NETDEV(5)                        systemd.network                        SYSTEMD.NETDEV(5)



NAME
       systemd.netdev - Virtual Network Device configuration

SYNOPSIS
       netdev.netdev

DESCRIPTION
       Network setup is performed by systemd-networkd(8).

       Virtual Network Device files must have the extension .netdev; other extensions are
       ignored. Virtual network devices are created as soon as networkd is started. If a netdev
       with the specified name already exists, networkd will use that as-is rather than create
       its own. Note that the settings of the pre-existing netdev will not be changed by
       networkd.

       The .netdev files are read from the files located in the system network directory
       /lib/systemd/network, the volatile runtime network directory /run/systemd/network and the
       local administration network directory /etc/systemd/network. All configuration files are
       collectively sorted and processed in lexical order, regardless of the directories in which
       they live. However, files with identical filenames replace each other. Files in /etc have
       the highest priority, files in /run take precedence over files with the same name in /lib.
       This can be used to override a system-supplied configuration file with a local file if
       needed; a symlink in /etc with the same name as a configuration file in /lib, pointing to
       /dev/null, disables the configuration file entirely.

[MATCH] SECTION OPTIONS
       A virtual network device is only created if the "[Match]" section matches the current
       environment, or if the section is empty. The following keys are accepted:

       Host=
           Matches against the hostname or machine ID of the host. See "ConditionHost=" in
           systemd.unit(5) for details.

       Virtualization=
           Checks whether the system is executed in a virtualized environment and optionally test
           whether it is a specific implementation. See "ConditionVirtualization=" in
           systemd.unit(5) for details.

       KernelCommandLine=
           Checks whether a specific kernel command line option is set (or if prefixed with the
           exclamation mark unset). See "ConditionKernelCommandLine=" in systemd.unit(5) for
           details.

       Architecture=
           Checks whether the system is running on a specific architecture. See
           "ConditionArchitecture=" in systemd.unit(5) for details.

[NETDEV] SECTION OPTIONS
       The "[NetDev]" section accepts the following keys:

       Description=
           A free-form description of the netdev.

       Name=
           The interface name used when creating the netdev. This option is compulsory.

       Kind=
           The netdev kind. Currently, "bridge", "bond", "vlan", "macvlan", "vxlan", "ipip",
           "gre", "sit", "vti", "veth", "tun", "tap" and "dummy" are supported. This option is
           compulsory.

       MTUBytes=
           The maximum transmission unit in bytes to set for the device. The usual suffixes K, M,
           G, are supported and are understood to the base of 1024.

       MACAddress=
           The MAC address to use for the device. If none is given, one is generated based on the
           interface name and the machine-id(5).

[VLAN] SECTION OPTIONS
       The "[VLAN]" section only applies for netdevs of kind "vlan", and accepts the following
       key:

       Id=
           The VLAN ID to use. An integer in the range 0–4094. This option is compulsory.

[MACVLAN] SECTION OPTIONS
       The "[MACVLAN]" section only applies for netdevs of kind "macvlan", and accepts the
       following key:

       Mode=
           The MACVLAN mode to use. The supported options are "private", "vepa", "bridge" and
           "passthru".

[VXLAN] SECTION OPTIONS
       The "[VXLAN]" section only applies for netdevs of kind "vxlan", and accepts the following
       key:

       Id=
           The VXLAN ID to use.

       Group=
           An assigned multicast group IP address.

       TOS=
           The Type Of Service byte value for a vxlan interface.

       TTL=
           A fixed Time To Live N on Virtual eXtensible Local Area Network packets. N is a number
           in the range 1-255. 0 is a special value meaning that packets inherit the TTL value.

       MacLearning=
           A boolean. When true, enables dynamic MAC learning to discover remote MAC addresses.

[TUNNEL] SECTION OPTIONS
       The "[Tunnel]" section only applies for netdevs of kind "ipip", "sit", "gre" and "vti" and
       accepts the following keys:

       Local=
           A static local address for tunneled packets. It must be an address on another
           interface of this host.

       Remote=
           The remote endpoint of the tunnel.

       TOS=
           The Type Of Service byte value for a tunnel interface. For details about the TOS see
           the Type of Service in the Internet Protocol Suite[1] document.

       TTL=
           A fixed Time To Live N on tunneled packets. N is a number in the range 1-255. 0 is a
           special value meaning that packets inherit the TTL value. The default value for IPv4
           tunnels is: inherit. The default value for IPv6 tunnels is: 64.

       DiscoverPathMTU=
           A boolean. When true, enables Path MTU Discovery on the tunnel.

[PEER] SECTION OPTIONS
       The "[Peer]" section only applies for netdevs of kind "veth" and accepts the following
       key:

       Name=
           The interface name used when creating the netdev. This option is compulsory.

       MACAddress=
           The peer MACAddress, if not set it is generated in the same way as the MAC address of
           the main interface.

[TUN] SECTION OPTIONS
       The "[Tun]" section only applies for netdevs of kind "tun", and accepts the following
       keys:

       OneQueue=
           Takes a boolean argument. Configures whether all packets are queued at the device
           (enabled), or a fixed number of packets are queued at the device and the rest at the
           "qdisc". Defaults to "no".

       MultiQueue=
           Takes a boolean argument. Configures whether to use multiple file descriptors (queues)
           to parallelize packets sending and receiving. Defaults to "no".

       PacketInfo=
           Takes a boolean argument. Configures whether packets should be prepened with four
           extra bytes (two flag bytes and two protocol bytes). If disabled it indicates that the
           packets will be pure IP packets. Defaults to "no".

       User=
           User to grant access to the /dev/net/tun device.

       Group=
           Group to grant access to the /dev/net/tun device.

[TAP] SECTION OPTIONS
       The "[Tap]" section only applies for netdevs of kind "tap", and accepts the same keys as
       the "[Tun]" section.

EXAMPLE
       Example 1. /etc/systemd/network/bridge.netdev

           [NetDev]
           Name=bridge0
           Kind=bridge

       Example 2. /etc/systemd/network/vlan1.netdev

           [Match]
           Virtualization=no

           [NetDev]
           Name=vlan1
           Kind=vlan

           [VLAN]
           Id=1

       Example 3. /etc/systemd/network/ipip.netdev

           [NetDev]
           Name=ipip-tun
           Kind=ipip
           MTUBytes=1480

           [Tunnel]
           Local=192.168.223.238
           Remote=192.169.224.239
           TTL=64

       Example 4. /etc/systemd/network/tap.netdev

           [NetDev]
           Name=tap-test
           Kind=tap

           [Tap]
           MultiQueue=true
           PacketInfo=true

       Example 5. /etc/systemd/network/sit.netdev

           [NetDev]
           Name=sit-tun
           Kind=sit
           MTUBytes=1480

           [Tunnel]
           Local=10.65.223.238
           Remote=10.65.223.239

       Example 6. /etc/systemd/network/gre.netdev

           [NetDev]
           Name=gre-tun
           Kind=gre
           MTUBytes=1480

           [Tunnel]
           Local=10.65.223.238
           Remote=10.65.223.239

       Example 7. /etc/systemd/network/vti.netdev

           [NetDev]
           Name=vti-tun
           Kind=vti
           MTUBytes=1480

           [Tunnel]
           Local=10.65.223.238
           Remote=10.65.223.239

       Example 8. /etc/systemd/network/veth.netdev

           [NetDev]
           Name=veth-test
           Kind=veth

           [Peer]
           Name=veth-peer

       Example 9. /etc/systemd/network/dummy.netdev

           [NetDev]
           Name=dummy-test
           Kind=dummy
           MACAddress=12:34:56:78:9a:bc

SEE ALSO
       systemd(1), systemd-networkd(8), systemd.network(5)

NOTES
        1. Type of Service in the Internet Protocol Suite
           http://tools.ietf.org/html/rfc1349



systemd 215                                                                     SYSTEMD.NETDEV(5)