systemd.netdev

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



NAME
       systemd.netdev - Virtual Network Device configuration

SYNOPSIS
       netdev.netdev

DESCRIPTION
       A plain ini-style text file that encodes configuration about a virtual
       network device, used by systemd-networkd(8). See systemd.syntax(7) for a
       general description of the syntax.

       The main Virtual Network Device file 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 /usr/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 /usr/lib/. This can be used
       to override a system-supplied configuration file with a local file if
       needed. As a special case, an empty file (file size 0) or symlink with
       the same name pointing to /dev/null disables the configuration file
       entirely (it is "masked").

       Along with the netdev file foo.netdev, a "drop-in" directory
       foo.netdev.d/ may exist. All files with the suffix ".conf" from this
       directory will be parsed after the file itself is parsed. This is useful
       to alter or add configuration settings, without having to modify the main
       configuration file. Each drop-in file must have appropriate section
       headers.

       In addition to /etc/systemd/network, drop-in ".d" directories can be
       placed in /usr/lib/systemd/network or /run/systemd/network directories.
       Drop-in files in /etc/ take precedence over those in /run/ which in turn
       take precedence over those in /usr/lib/. Drop-in files under any of these
       directories take precedence over the main netdev file wherever located.
       (Of course, since /run/ is temporary and /usr/lib/ is for vendors, it is
       unlikely drop-ins should be used in either of those places.)

SUPPORTED NETDEV KINDS
       The following kinds of virtual network devices may be configured in
       .netdev files:

       Table 1. Supported kinds of virtual network devices
       ┌──────────┬─────────────────────────────┐
       │Kind      Description                 │
       ├──────────┼─────────────────────────────┤
       │bond      │ A bond device is an         │
       │          │ aggregation of all its      │
       │          │ slave devices. See Linux    │
       │          │ Ethernet Bonding Driver     │
       │          │ HOWTO[1] for details.       │
       ├──────────┼─────────────────────────────┤
       │bridge    │ A bridge device is a        │
       │          │ software switch, and each   │
       │          │ of its slave devices and    │
       │          │ the bridge itself are ports │
       │          │ of the switch.              │
       ├──────────┼─────────────────────────────┤
       │dummy     │ A dummy device drops all    │
       │          │ packets sent to it.         │
       ├──────────┼─────────────────────────────┤
       │gre       │ A Level 3 GRE tunnel over   │
       │          │ IPv4. See RFC 2784[2] for   │
       │          │ details.                    │
       ├──────────┼─────────────────────────────┤
       │gretap    │ A Level 2 GRE tunnel over   │
       │          │ IPv4.                       │
       ├──────────┼─────────────────────────────┤
       │erspan    │ ERSPAN mirrors traffic on   │
       │          │ one or more source ports    │
       │          │ and delivers the mirrored   │
       │          │ traffic to one or more      │
       │          │ destination ports on        │
       │          │ another switch. The traffic │
       │          │ is encapsulated in generic  │
       │          │ routing encapsulation (GRE) │
       │          │ and is therefore routable   │
       │          │ across a layer 3 network    │
       │          │ between the source switch   │
       │          │ and the destination switch. │
       ├──────────┼─────────────────────────────┤
       │ip6gre    │ A Level 3 GRE tunnel over   │
       │          │ IPv6.                       │
       ├──────────┼─────────────────────────────┤
       │ip6tnl    │ An IPv4 or IPv6 tunnel over │
       │          │ IPv6                        │
       ├──────────┼─────────────────────────────┤
       │ip6gretap │ A Level 2 GRE tunnel over   │
       │          │ IPv6.                       │
       ├──────────┼─────────────────────────────┤
       │ipip      │ An IPv4 over IPv4 tunnel.   │
       ├──────────┼─────────────────────────────┤
       │ipvlan    │ An IPVLAN device is a       │
       │          │ stacked device which        │
       │          │ receives packets from its   │
       │          │ underlying device based on  │
       │          │ IP address filtering.       │
       ├──────────┼─────────────────────────────┤
       │ipvtap    │ An IPVTAP device is a       │
       │          │ stacked device which        │
       │          │ receives packets from its   │
       │          │ underlying device based on  │
       │          │ IP address filtering and    │
       │          │ can be accessed using the   │
       │          │ tap user space interface.   │
       ├──────────┼─────────────────────────────┤
       │macvlan   │ A macvlan device is a       │
       │          │ stacked device which        │
       │          │ receives packets from its   │
       │          │ underlying device based on  │
       │          │ MAC address filtering.      │
       ├──────────┼─────────────────────────────┤
       │macvtap   │ A macvtap device is a       │
       │          │ stacked device which        │
       │          │ receives packets from its   │
       │          │ underlying device based on  │
       │          │ MAC address filtering.      │
       ├──────────┼─────────────────────────────┤
       │sit       │ An IPv6 over IPv4 tunnel.   │
       ├──────────┼─────────────────────────────┤
       │tap       │ A persistent Level 2 tunnel │
       │          │ between a network device    │
       │          │ and a device node.          │
       ├──────────┼─────────────────────────────┤
       │tun       │ A persistent Level 3 tunnel │
       │          │ between a network device    │
       │          │ and a device node.          │
       ├──────────┼─────────────────────────────┤
       │veth      │ An Ethernet tunnel between  │
       │          │ a pair of network devices.  │
       ├──────────┼─────────────────────────────┤
       │vlan      │ A VLAN is a stacked device  │
       │          │ which receives packets from │
       │          │ its underlying device based │
       │          │ on VLAN tagging. See IEEE   │
       │          │ 802.1Q[3] for details.      │
       ├──────────┼─────────────────────────────┤
       │vti       │ An IPv4 over IPSec tunnel.  │
       ├──────────┼─────────────────────────────┤
       │vti6      │ An IPv6 over IPSec tunnel.  │
       ├──────────┼─────────────────────────────┤
       │vxlan     │ A virtual extensible LAN    │
       │          │ (vxlan), for connecting     │
       │          │ Cloud computing             │
       │          │ deployments.                │
       ├──────────┼─────────────────────────────┤
       │geneve    │ A GEneric NEtwork           │
       │          │ Virtualization              │
       │          │ Encapsulation (GENEVE)      │
       │          │ netdev driver.              │
       ├──────────┼─────────────────────────────┤
       │l2tp      │ A Layer 2 Tunneling         │
       │          │ Protocol (L2TP) is a        │
       │          │ tunneling protocol used to  │
       │          │ support virtual private     │
       │          │ networks (VPNs) or as part  │
       │          │ of the delivery of services │
       │          │ by ISPs. It does not        │
       │          │ provide any encryption or   │
       │          │ confidentiality by itself   │
       ├──────────┼─────────────────────────────┤
       │macsec    │ Media Access Control        │
       │          │ Security (MACsec) is an     │
       │          │ 802.1AE IEEE                │
       │          │ industry-standard security  │
       │          │ technology that provides    │
       │          │ secure communication for    │
       │          │ all traffic on Ethernet     │
       │          │ links. MACsec provides      │
       │          │ point-to-point security on  │
       │          │ Ethernet links between      │
       │          │ directly connected nodes    │
       │          │ and is capable of           │
       │          │ identifying and preventing  │
       │          │ most security threats.      │
       ├──────────┼─────────────────────────────┤
       │vrf       │ A Virtual Routing and       │
       │          │ Forwarding (VRF[4])         │
       │          │ interface to create         │
       │          │ separate routing and        │
       │          │ forwarding domains.         │
       ├──────────┼─────────────────────────────┤
       │vcan      │ The virtual CAN driver      │
       │          │ (vcan). Similar to the      │
       │          │ network loopback devices,   │
       │          │ vcan offers a virtual local │
       │          │ CAN interface.              │
       ├──────────┼─────────────────────────────┤
       │vxcan     │ The virtual CAN tunnel      │
       │          │ driver (vxcan). Similar to  │
       │          │ the virtual ethernet driver │
       │          │ veth, vxcan implements a    │
       │          │ local CAN traffic tunnel    │
       │          │ between two virtual CAN     │
       │          │ network devices. When       │
       │          │ creating a vxcan, two vxcan │
       │          │ devices are created as      │
       │          │ pair. When one end receives │
       │          │ the packet it appears on    │
       │          │ its pair and vice versa.    │
       │          │ The vxcan can be used for   │
       │          │ cross namespace             │
       │          │ communication.              │
       ├──────────┼─────────────────────────────┤
       │wireguard │ WireGuard Secure Network    │
       │          │ Tunnel.                     │
       ├──────────┼─────────────────────────────┤
       │nlmon     │ A Netlink monitor device.   │
       │          │ Use an nlmon device when    │
       │          │ you want to monitor system  │
       │          │ Netlink messages.           │
       ├──────────┼─────────────────────────────┤
       │fou       │ Foo-over-UDP tunneling.     │
       ├──────────┼─────────────────────────────┤
       │xfrm      │ A virtual tunnel interface  │
       │          │ like vti/vti6 but with      │
       │          │ several advantages.         │
       ├──────────┼─────────────────────────────┤
       │ifb       │ The Intermediate Functional │
       │          │ Block (ifb) pseudo network  │
       │          │ interface acts as a QoS     │
       │          │ concentrator for multiple   │
       │          │ different sources of        │
       │          │ traffic.                    │
       ├──────────┼─────────────────────────────┤
       │bareudp   │ Bare UDP tunnels provide a  │
       │          │ generic L3 encapsulation    │
       │          │ support for tunnelling      │
       │          │ different L3 protocols like │
       │          │ MPLS, IP etc. inside of an  │
       │          │ UDP tunnel.                 │
       └──────────┴─────────────────────────────┘

[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. When prefixed with
           an exclamation mark ("!"), the result is negated. If an empty string
           is assigned, then previously assigned value is cleared.

       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. When
           prefixed with an exclamation mark ("!"), the result is negated. If an
           empty string is assigned, then previously assigned value is cleared.

       KernelCommandLine=
           Checks whether a specific kernel command line option is set. See
           "ConditionKernelCommandLine=" in systemd.unit(5) for details. When
           prefixed with an exclamation mark ("!"), the result is negated. If an
           empty string is assigned, then previously assigned value is cleared.

       KernelVersion=
           Checks whether the kernel version (as reported by uname -r) matches a
           certain expression. See "ConditionKernelVersion=" in systemd.unit(5)
           for details. When prefixed with an exclamation mark ("!"), the result
           is negated. If an empty string is assigned, then previously assigned
           value is cleared.

       Architecture=
           Checks whether the system is running on a specific architecture. See
           "ConditionArchitecture=" in systemd.unit(5) for details. When
           prefixed with an exclamation mark ("!"), the result is negated. If an
           empty string is assigned, then previously assigned value is cleared.

[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 setting is
           compulsory.

       Kind=
           The netdev kind. This setting is compulsory. See the "Supported
           netdev kinds" section for the valid keys.

       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. For "tun" or "tap" devices, MTUBytes= setting is not
           currently supported in [NetDev] section. Please specify it in [Link]
           section of corresponding systemd.network(5) files.

       MACAddress=
           The MAC address to use for the device. For "tun" or "tap" devices,
           setting MACAddress= in the [NetDev] section is not supported. Please
           specify it in [Link] section of the corresponding systemd.network(5)
           file. If this option is not set, "vlan" devices inherit the MAC
           address of the physical interface. For other kind of netdevs, if this
           option is not set, then MAC address is generated based on the
           interface name and the machine-id(5).

[BRIDGE] SECTION OPTIONS
       The [Bridge] section only applies for netdevs of kind "bridge", and
       accepts the following keys:

       HelloTimeSec=
           HelloTimeSec specifies the number of seconds between two hello
           packets sent out by the root bridge and the designated bridges. Hello
           packets are used to communicate information about the topology
           throughout the entire bridged local area network.

       MaxAgeSec=
           MaxAgeSec specifies the number of seconds of maximum message age. If
           the last seen (received) hello packet is more than this number of
           seconds old, the bridge in question will start the takeover procedure
           in attempt to become the Root Bridge itself.

       ForwardDelaySec=
           ForwardDelaySec specifies the number of seconds spent in each of the
           Listening and Learning states before the Forwarding state is entered.

       AgeingTimeSec=
           This specifies the number of seconds a MAC Address will be kept in
           the forwarding database after having a packet received from this MAC
           Address.

       Priority=
           The priority of the bridge. An integer between 0 and 65535. A lower
           value means higher priority. The bridge having the lowest priority
           will be elected as root bridge.

       GroupForwardMask=
           A 16-bit bitmask represented as an integer which allows forwarding of
           link local frames with 802.1D reserved addresses (01:80:C2:00:00:0X).
           A logical AND is performed between the specified bitmask and the
           exponentiation of 2^X, the lower nibble of the last octet of the MAC
           address. For example, a value of 8 would allow forwarding of frames
           addressed to 01:80:C2:00:00:03 (802.1X PAE).

       DefaultPVID=
           This specifies the default port VLAN ID of a newly attached bridge
           port. Set this to an integer in the range 1–4094 or "none" to disable
           the PVID.

       MulticastQuerier=
           Takes a boolean. This setting controls the IFLA_BR_MCAST_QUERIER
           option in the kernel. If enabled, the kernel will send general ICMP
           queries from a zero source address. This feature should allow faster
           convergence on startup, but it causes some multicast-aware switches
           to misbehave and disrupt forwarding of multicast packets. When unset,
           the kernel's default will be used.

       MulticastSnooping=
           Takes a boolean. This setting controls the IFLA_BR_MCAST_SNOOPING
           option in the kernel. If enabled, IGMP snooping monitors the Internet
           Group Management Protocol (IGMP) traffic between hosts and multicast
           routers. When unset, the kernel's default will be used.

       VLANFiltering=
           Takes a boolean. This setting controls the IFLA_BR_VLAN_FILTERING
           option in the kernel. If enabled, the bridge will be started in
           VLAN-filtering mode. When unset, the kernel's default will be used.

       VLANProtocol=
           Allows setting the protocol used for VLAN filtering. Takes 802.1q or,
           802.1ad, and defaults to unset and kernel's default is used.

       STP=
           Takes a boolean. This enables the bridge's Spanning Tree Protocol
           (STP). When unset, the kernel's default will be used.

       MulticastIGMPVersion=
           Allows changing bridge's multicast Internet Group Management Protocol
           (IGMP) version. Takes an integer 2 or 3. When unset, the kernel's
           default will be used.

[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 setting is
           compulsory.

       GVRP=
           Takes a boolean. The Generic VLAN Registration Protocol (GVRP) is a
           protocol that allows automatic learning of VLANs on a network. When
           unset, the kernel's default will be used.

       MVRP=
           Takes a boolean. Multiple VLAN Registration Protocol (MVRP) formerly
           known as GARP VLAN Registration Protocol (GVRP) is a standards-based
           Layer 2 network protocol, for automatic configuration of VLAN
           information on switches. It was defined in the 802.1ak amendment to
           802.1Q-2005. When unset, the kernel's default will be used.

       LooseBinding=
           Takes a boolean. The VLAN loose binding mode, in which only the
           operational state is passed from the parent to the associated VLANs,
           but the VLAN device state is not changed. When unset, the kernel's
           default will be used.

       ReorderHeader=
           Takes a boolean. When enabled, the VLAN reorder header is used and
           VLAN interfaces behave like physical interfaces. When unset, the
           kernel's default will be used.

[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", "passthru", and "source".

       SourceMACAddress=
           A whitespace-separated list of remote hardware addresses allowed on
           the MACVLAN. This option only has an effect in source mode. Use full
           colon-, hyphen- or dot-delimited hexadecimal. This option may appear
           more than once, in which case the lists are merged. If the empty
           string is assigned to this option, the list of hardware addresses
           defined prior to this is reset. Defaults to unset.

[MACVTAP] SECTION OPTIONS
       The [MACVTAP] section applies for netdevs of kind "macvtap" and accepts
       the same keys as [MACVLAN].

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

       Mode=
           The IPVLAN mode to use. The supported options are "L2","L3" and
           "L3S".

       Flags=
           The IPVLAN flags to use. The supported options are "bridge","private"
           and "vepa".

[IPVTAP] SECTION OPTIONS
       The [IPVTAP] section only applies for netdevs of kind "ipvtap" and
       accepts the same keys as [IPVLAN].

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

       VNI=
           The VXLAN Network Identifier (or VXLAN Segment ID). Takes a number in
           the range 1-16777215.

       Remote=
           Configures destination IP address.

       Local=
           Configures local IP address.

       Group=
           Configures VXLAN multicast group IP address. All members of a VXLAN
           must use the same multicast group 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. Takes "inherit" or a number in the range 0–255. 0 is a
           special value meaning inherit the inner protocol's TTL value.
           "inherit" means that it will inherit the outer protocol's TTL value.

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

       FDBAgeingSec=
           The lifetime of Forwarding Database entry learnt by the kernel, in
           seconds.

       MaximumFDBEntries=
           Configures maximum number of FDB entries.

       ReduceARPProxy=
           Takes a boolean. When true, bridge-connected VXLAN tunnel endpoint
           answers ARP requests from the local bridge on behalf of remote
           Distributed Overlay Virtual Ethernet (DVOE)[5] clients. Defaults to
           false.

       L2MissNotification=
           Takes a boolean. When true, enables netlink LLADDR miss
           notifications.

       L3MissNotification=
           Takes a boolean. When true, enables netlink IP address miss
           notifications.

       RouteShortCircuit=
           Takes a boolean. When true, route short circuiting is turned on.

       UDPChecksum=
           Takes a boolean. When true, transmitting UDP checksums when doing
           VXLAN/IPv4 is turned on.

       UDP6ZeroChecksumTx=
           Takes a boolean. When true, sending zero checksums in VXLAN/IPv6 is
           turned on.

       UDP6ZeroChecksumRx=
           Takes a boolean. When true, receiving zero checksums in VXLAN/IPv6 is
           turned on.

       RemoteChecksumTx=
           Takes a boolean. When true, remote transmit checksum offload of VXLAN
           is turned on.

       RemoteChecksumRx=
           Takes a boolean. When true, remote receive checksum offload in VXLAN
           is turned on.

       GroupPolicyExtension=
           Takes a boolean. When true, it enables Group Policy VXLAN extension
           security label mechanism across network peers based on VXLAN. For
           details about the Group Policy VXLAN, see the VXLAN Group Policy[6]
           document. Defaults to false.

       GenericProtocolExtension=
           Takes a boolean. When true, Generic Protocol Extension extends the
           existing VXLAN protocol to provide protocol typing, OAM, and
           versioning capabilities. For details about the VXLAN GPE Header, see
           the Generic Protocol Extension for VXLAN[7] document. If destination
           port is not specified and Generic Protocol Extension is set then
           default port of 4790 is used. Defaults to false.

       DestinationPort=
           Configures the default destination UDP port. If the destination port
           is not specified then Linux kernel default will be used. Set to 4789
           to get the IANA assigned value.

       PortRange=
           Configures the source port range for the VXLAN. The kernel assigns
           the source UDP port based on the flow to help the receiver to do load
           balancing. When this option is not set, the normal range of local UDP
           ports is used.

       FlowLabel=
           Specifies the flow label to use in outgoing packets. The valid range
           is 0-1048575.

       IPDoNotFragment=
           Allows setting the IPv4 Do not Fragment (DF) bit in outgoing packets,
           or to inherit its value from the IPv4 inner header. Takes a boolean
           value, or "inherit". Set to "inherit" if the encapsulated protocol is
           IPv6. When unset, the kernel's default will be used.

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

       Id=
           Specifies the Virtual Network Identifier (VNI) to use, a number
           between 0 and 16777215. This field is mandatory.

       Remote=
           Specifies the unicast destination IP address to use in outgoing
           packets.

       TOS=
           Specifies the TOS value to use in outgoing packets. Takes a number
           between 1 and 255.

       TTL=
           Accepts the same values as in the [VXLAN] section, except that when
           unset or set to 0, the kernel's default will be used, meaning that
           packet TTL will be set from /proc/sys/net/ipv4/ip_default_ttl.

       UDPChecksum=
           Takes a boolean. When true, specifies that UDP checksum is calculated
           for transmitted packets over IPv4.

       UDP6ZeroChecksumTx=
           Takes a boolean. When true, skip UDP checksum calculation for
           transmitted packets over IPv6.

       UDP6ZeroChecksumRx=
           Takes a boolean. When true, allows incoming UDP packets over IPv6
           with zero checksum field.

       DestinationPort=
           Specifies destination port. Defaults to 6081. If not set or assigned
           the empty string, the default port of 6081 is used.

       FlowLabel=
           Specifies the flow label to use in outgoing packets.

       IPDoNotFragment=
           Accepts the same key as in [VXLAN] section.

       Independent=
           Takes a boolean. When true, the vxlan interface is created without
           any underlying network interface. Defaults to false, which means that
           a .network file that requests this tunnel using Tunnel= is required
           for the tunnel to be created.

[BAREUDP] SECTION OPTIONS
       The [BareUDP] section only applies for netdevs of kind "bareudp", and
       accepts the following keys:

       DestinationPort=
           Specifies the destination UDP port (in range 1...65535). This is
           mandatory.

       EtherType=
           Specifies the L3 protocol. Takes one of "ipv4", "ipv6", "mpls-uc" or
           "mpls-mc". This is mandatory.

[L2TP] SECTION OPTIONS
       The [L2TP] section only applies for netdevs of kind "l2tp", and accepts
       the following keys:

       TunnelId=
           Specifies the tunnel identifier. Takes an number in the range
           1–4294967295. The value used must match the "PeerTunnelId=" value
           being used at the peer. This setting is compulsory.

       PeerTunnelId=
           Specifies the peer tunnel id. Takes a number in the range
           1—4294967295. The value used must match the "TunnelId=" value being
           used at the peer. This setting is compulsory.

       Remote=
           Specifies the IP address of the remote peer. This setting is
           compulsory.

       Local=
           Specifies the IP address of the local interface. Takes an IP address,
           or the special values "auto", "static", or "dynamic". When an address
           is set, then the local interface must have the address. If "auto",
           then one of the addresses on the local interface is used. Similarly,
           if "static" or "dynamic" is set, then one of the static or dynamic
           addresses on the local interface is used. Defaults to "auto".

       EncapsulationType=
           Specifies the encapsulation type of the tunnel. Takes one of "udp" or
           "ip".

       UDPSourcePort=
           Specifies the UDP source port to be used for the tunnel. When UDP
           encapsulation is selected it's mandatory. Ignored when IP
           encapsulation is selected.

       UDPDestinationPort=
           Specifies destination port. When UDP encapsulation is selected it's
           mandatory. Ignored when IP encapsulation is selected.

       UDPChecksum=
           Takes a boolean. When true, specifies that UDP checksum is calculated
           for transmitted packets over IPv4.

       UDP6ZeroChecksumTx=
           Takes a boolean. When true, skip UDP checksum calculation for
           transmitted packets over IPv6.

       UDP6ZeroChecksumRx=
           Takes a boolean. When true, allows incoming UDP packets over IPv6
           with zero checksum field.

[L2TPSESSION] SECTION OPTIONS
       The [L2TPSession] section only applies for netdevs of kind "l2tp", and
       accepts the following keys:

       Name=
           Specifies the name of the session. This setting is compulsory.

       SessionId=
           Specifies the session identifier. Takes an number in the range
           1–4294967295. The value used must match the "SessionId=" value being
           used at the peer. This setting is compulsory.

       PeerSessionId=
           Specifies the peer session identifier. Takes an number in the range
           1–4294967295. The value used must match the "PeerSessionId=" value
           being used at the peer. This setting is compulsory.

       Layer2SpecificHeader=
           Specifies layer2specific header type of the session. One of "none" or
           "default". Defaults to "default".

[MACSEC] SECTION OPTIONS
       The [MACsec] section only applies for network devices of kind "macsec",
       and accepts the following keys:

       Port=
           Specifies the port to be used for the MACsec transmit channel. The
           port is used to make secure channel identifier (SCI). Takes a value
           between 1 and 65535. Defaults to unset.

       Encrypt=
           Takes a boolean. When true, enable encryption. Defaults to unset.

[MACSECRECEIVECHANNEL] SECTION OPTIONS
       The [MACsecReceiveChannel] section only applies for network devices of
       kind "macsec", and accepts the following keys:

       Port=
           Specifies the port to be used for the MACsec receive channel. The
           port is used to make secure channel identifier (SCI). Takes a value
           between 1 and 65535. This option is compulsory, and is not set by
           default.

       MACAddress=
           Specifies the MAC address to be used for the MACsec receive channel.
           The MAC address used to make secure channel identifier (SCI). This
           setting is compulsory, and is not set by default.

[MACSECTRANSMITASSOCIATION] SECTION OPTIONS
       The [MACsecTransmitAssociation] section only applies for network devices
       of kind "macsec", and accepts the following keys:

       PacketNumber=
           Specifies the packet number to be used for replay protection and the
           construction of the initialization vector (along with the secure
           channel identifier [SCI]). Takes a value between 1-4,294,967,295.
           Defaults to unset.

       KeyId=
           Specifies the identification for the key. Takes a number between
           0-255. This option is compulsory, and is not set by default.

       Key=
           Specifies the encryption key used in the transmission channel. The
           same key must be configured on the peer’s matching receive channel.
           This setting is compulsory, and is not set by default. Takes a
           128-bit key encoded in a hexadecimal string, for example
           "dffafc8d7b9a43d5b9a3dfbbf6a30c16".

       KeyFile=
           Takes a absolute path to a file which contains a 128-bit key encoded
           in a hexadecimal string, which will be used in the transmission
           channel. When this option is specified, Key= is ignored. Note that
           the file must be readable by the user "systemd-network", so it should
           be, e.g., owned by "root:systemd-network" with a "0640" file mode. If
           the path refers to an AF_UNIX stream socket in the file system a
           connection is made to it and the key read from it.

       Activate=
           Takes a boolean. If enabled, then the security association is
           activated. Defaults to unset.

       UseForEncoding=
           Takes a boolean. If enabled, then the security association is used
           for encoding. Only one [MACsecTransmitAssociation] section can enable
           this option. When enabled, Activate=yes is implied. Defaults to
           unset.

[MACSECRECEIVEASSOCIATION] SECTION OPTIONS
       The [MACsecReceiveAssociation] section only applies for network devices
       of kind "macsec", and accepts the following keys:

       Port=
           Accepts the same key as in [MACsecReceiveChannel] section.

       MACAddress=
           Accepts the same key as in [MACsecReceiveChannel] section.

       PacketNumber=
           Accepts the same key as in [MACsecTransmitAssociation] section.

       KeyId=
           Accepts the same key as in [MACsecTransmitAssociation] section.

       Key=
           Accepts the same key as in [MACsecTransmitAssociation] section.

       KeyFile=
           Accepts the same key as in [MACsecTransmitAssociation] section.

       Activate=
           Accepts the same key as in [MACsecTransmitAssociation] section.

[TUNNEL] SECTION OPTIONS
       The [Tunnel] section only applies for netdevs of kind "ipip", "sit",
       "gre", "gretap", "ip6gre", "ip6gretap", "vti", "vti6", "ip6tnl", and
       "erspan" and accepts the following keys:

       Local=
           A static local address for tunneled packets. It must be an address on
           another interface of this host, or the special value "any".

       Remote=
           The remote endpoint of the tunnel. Takes an IP address or the special
           value "any".

       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[8] 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 0 (inherit). The
           default value for IPv6 tunnels is 64.

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

       IPv6FlowLabel=
           Configures the 20-bit flow label (see RFC 6437[9]) field in the IPv6
           header (see RFC 2460[10]), which is used by a node to label packets
           of a flow. It is only used for IPv6 tunnels. A flow label of zero is
           used to indicate packets that have not been labeled. It can be
           configured to a value in the range 0–0xFFFFF, or be set to "inherit",
           in which case the original flowlabel is used.

       CopyDSCP=
           Takes a boolean. When true, the Differentiated Service Code Point
           (DSCP) field will be copied to the inner header from outer header
           during the decapsulation of an IPv6 tunnel packet. DSCP is a field in
           an IP packet that enables different levels of service to be assigned
           to network traffic. Defaults to "no".

       EncapsulationLimit=
           The Tunnel Encapsulation Limit option specifies how many additional
           levels of encapsulation are permitted to be prepended to the packet.
           For example, a Tunnel Encapsulation Limit option containing a limit
           value of zero means that a packet carrying that option may not enter
           another tunnel before exiting the current tunnel. (see RFC 2473[11]).
           The valid range is 0–255 and "none". Defaults to 4.

       Key=
           The Key= parameter specifies the same key to use in both directions
           (InputKey= and OutputKey=). The Key= is either a number or an IPv4
           address-like dotted quad. It is used as mark-configured SAD/SPD entry
           as part of the lookup key (both in data and control path) in IP XFRM
           (framework used to implement IPsec protocol). See ip-xfrm — transform
           configuration[12] for details. It is only used for VTI/VTI6, GRE,
           GRETAP, and ERSPAN tunnels.

       InputKey=
           The InputKey= parameter specifies the key to use for input. The
           format is same as Key=. It is only used for VTI/VTI6, GRE, GRETAP,
           and ERSPAN tunnels.

       OutputKey=
           The OutputKey= parameter specifies the key to use for output. The
           format is same as Key=. It is only used for VTI/VTI6, GRE, GRETAP,
           and ERSPAN tunnels.

       Mode=
           An "ip6tnl" tunnel can be in one of three modes "ip6ip6" for IPv6
           over IPv6, "ipip6" for IPv4 over IPv6 or "any" for either.

       Independent=
           Takes a boolean. When false (the default), the tunnel is always
           created over some network device, and a .network file that requests
           this tunnel using Tunnel= is required for the tunnel to be created.
           When true, the tunnel is created independently of any network as
           "tunnel@NONE".

       AssignToLoopback=
           Takes a boolean. If set to "yes", the loopback interface "lo" is used
           as the underlying device of the tunnel interface. Defaults to "no".

       AllowLocalRemote=
           Takes a boolean. When true allows tunnel traffic on ip6tnl devices
           where the remote endpoint is a local host address. When unset, the
           kernel's default will be used.

       FooOverUDP=
           Takes a boolean. Specifies whether FooOverUDP= tunnel is to be
           configured. Defaults to false. This takes effects only for IPIP, SIT,
           GRE, and GRETAP tunnels. For more detail information see Foo over
           UDP[13]

       FOUDestinationPort=
           This setting specifies the UDP destination port for encapsulation.
           This field is mandatory when FooOverUDP=yes, and is not set by
           default.

       FOUSourcePort=
           This setting specifies the UDP source port for encapsulation.
           Defaults to 0 — that is, the source port for packets is left to the
           network stack to decide.

       Encapsulation=
           Accepts the same key as in the [FooOverUDP] section.

       IPv6RapidDeploymentPrefix=
           Reconfigure the tunnel for IPv6 Rapid Deployment[14], also known as
           6rd. The value is an ISP-specific IPv6 prefix with a non-zero length.
           Only applicable to SIT tunnels.

       ISATAP=
           Takes a boolean. If set, configures the tunnel as Intra-Site
           Automatic Tunnel Addressing Protocol (ISATAP) tunnel. Only applicable
           to SIT tunnels. When unset, the kernel's default will be used.

       SerializeTunneledPackets=
           Takes a boolean. If set to yes, then packets are serialized. Only
           applies for GRE, GRETAP, and ERSPAN tunnels. When unset, the kernel's
           default will be used.

       ERSPANIndex=
           Specifies the ERSPAN index field for the interface, an integer in the
           range 1-1048575 associated with the ERSPAN traffic's source port and
           direction. This field is mandatory.

[FOOOVERUDP] SECTION OPTIONS
       The [FooOverUDP] section only applies for netdevs of kind "fou" and
       accepts the following keys:

       Encapsulation=
           Specifies the encapsulation mechanism used to store networking
           packets of various protocols inside the UDP packets. Supports the
           following values: "FooOverUDP" provides the simplest no-frills model
           of UDP encapsulation, it simply encapsulates packets directly in the
           UDP payload.  "GenericUDPEncapsulation" is a generic and extensible
           encapsulation, it allows encapsulation of packets for any IP protocol
           and optional data as part of the encapsulation. For more detailed
           information see Generic UDP Encapsulation[15]. Defaults to
           "FooOverUDP".

       Port=
           Specifies the port number where the encapsulated packets will arrive.
           Those packets will be removed and manually fed back into the network
           stack with the encapsulation removed to be sent to the real
           destination. This option is mandatory.

       PeerPort=
           Specifies the peer port number. Defaults to unset. Note that when
           peer port is set "Peer=" address is mandatory.

       Protocol=
           The Protocol= specifies the protocol number of the packets arriving
           at the UDP port. When Encapsulation=FooOverUDP, this field is
           mandatory and is not set by default. Takes an IP protocol name such
           as "gre" or "ipip", or an integer within the range 1-255. When
           Encapsulation=GenericUDPEncapsulation, this must not be specified.

       Peer=
           Configures peer IP address. Note that when peer address is set
           "PeerPort=" is mandatory.

       Local=
           Configures local IP address.

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

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

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

[VXCAN] SECTION OPTIONS
       The [VXCAN] section only applies for netdevs of kind "vxcan" and accepts
       the following key:

       Peer=
           The peer interface name used when creating the netdev. This setting
           is compulsory.

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

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

       PacketInfo=
           Takes a boolean. Configures whether packets should be prepended 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".

       VNetHeader=
           Takes a boolean. Configures IFF_VNET_HDR flag for a tun or tap
           device. It allows sending and receiving larger Generic Segmentation
           Offload (GSO) packets. This may increase throughput significantly.
           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.

[WIREGUARD] SECTION OPTIONS
       The [WireGuard] section accepts the following keys:

       PrivateKey=
           The Base64 encoded private key for the interface. It can be generated
           using the wg genkey command (see wg(8)). This option or
           PrivateKeyFile= is mandatory to use WireGuard. Note that because this
           information is secret, you may want to set the permissions of the
           .netdev file to be owned by "root:systemd-network" with a "0640" file
           mode.

       PrivateKeyFile=
           Takes an absolute path to a file which contains the Base64 encoded
           private key for the interface. When this option is specified, then
           PrivateKey= is ignored. Note that the file must be readable by the
           user "systemd-network", so it should be, e.g., owned by
           "root:systemd-network" with a "0640" file mode. If the path refers to
           an AF_UNIX stream socket in the file system a connection is made to
           it and the key read from it.

       ListenPort=
           Sets UDP port for listening. Takes either value between 1 and 65535
           or "auto". If "auto" is specified, the port is automatically
           generated based on interface name. Defaults to "auto".

       FirewallMark=
           Sets a firewall mark on outgoing WireGuard packets from this
           interface. Takes a number between 1 and 4294967295.

[WIREGUARDPEER] SECTION OPTIONS
       The [WireGuardPeer] section accepts the following keys:

       PublicKey=
           Sets a Base64 encoded public key calculated by wg pubkey (see wg(8))
           from a private key, and usually transmitted out of band to the author
           of the configuration file. This option is mandatory for this section.

       PresharedKey=
           Optional preshared key for the interface. It can be generated by the
           wg genpsk command. This option adds an additional layer of
           symmetric-key cryptography to be mixed into the already existing
           public-key cryptography, for post-quantum resistance. Note that
           because this information is secret, you may want to set the
           permissions of the .netdev file to be owned by "root:systemd-network"
           with a "0640" file mode.

       PresharedKeyFile=
           Takes an absolute path to a file which contains the Base64 encoded
           preshared key for the peer. When this option is specified, then
           PresharedKey= is ignored. Note that the file must be readable by the
           user "systemd-network", so it should be, e.g., owned by
           "root:systemd-network" with a "0640" file mode. If the path refers to
           an AF_UNIX stream socket in the file system a connection is made to
           it and the key read from it.

       AllowedIPs=
           Sets a comma-separated list of IP (v4 or v6) addresses with CIDR
           masks from which this peer is allowed to send incoming traffic and to
           which outgoing traffic for this peer is directed.

           The catch-all 0.0.0.0/0 may be specified for matching all IPv4
           addresses, and ::/0 may be specified for matching all IPv6 addresses.

           Note that this only affects "routing inside the network interface
           itself", as in, which wireguard peer packets with a specific
           destination address are sent to, and what source addresses are
           accepted from which peer.

           To cause packets to be sent via wireguard in first place, a route
           needs to be added, as well - either in the "[Routes]" section on the
           ".network" matching the wireguard interface, or outside of networkd.

       Endpoint=
           Sets an endpoint IP address or hostname, followed by a colon, and
           then a port number. This endpoint will be updated automatically once
           to the most recent source IP address and port of correctly
           authenticated packets from the peer at configuration time.

       PersistentKeepalive=
           Sets a seconds interval, between 1 and 65535 inclusive, of how often
           to send an authenticated empty packet to the peer for the purpose of
           keeping a stateful firewall or NAT mapping valid persistently. For
           example, if the interface very rarely sends traffic, but it might at
           anytime receive traffic from a peer, and it is behind NAT, the
           interface might benefit from having a persistent keepalive interval
           of 25 seconds. If set to 0 or "off", this option is disabled. By
           default or when unspecified, this option is off. Most users will not
           need this.

[BOND] SECTION OPTIONS
       The [Bond] section accepts the following key:

       Mode=
           Specifies one of the bonding policies. The default is "balance-rr"
           (round robin). Possible values are "balance-rr", "active-backup",
           "balance-xor", "broadcast", "802.3ad", "balance-tlb", and
           "balance-alb".

       TransmitHashPolicy=
           Selects the transmit hash policy to use for slave selection in
           balance-xor, 802.3ad, and tlb modes. Possible values are "layer2",
           "layer3+4", "layer2+3", "encap2+3", and "encap3+4".

       LACPTransmitRate=
           Specifies the rate with which link partner transmits Link Aggregation
           Control Protocol Data Unit packets in 802.3ad mode. Possible values
           are "slow", which requests partner to transmit LACPDUs every 30
           seconds, and "fast", which requests partner to transmit LACPDUs every
           second. The default value is "slow".

       MIIMonitorSec=
           Specifies the frequency that Media Independent Interface link
           monitoring will occur. A value of zero disables MII link monitoring.
           This value is rounded down to the nearest millisecond. The default
           value is 0.

       UpDelaySec=
           Specifies the delay before a link is enabled after a link up status
           has been detected. This value is rounded down to a multiple of
           MIIMonitorSec. The default value is 0.

       DownDelaySec=
           Specifies the delay before a link is disabled after a link down
           status has been detected. This value is rounded down to a multiple of
           MIIMonitorSec. The default value is 0.

       LearnPacketIntervalSec=
           Specifies the number of seconds between instances where the bonding
           driver sends learning packets to each slave peer switch. The valid
           range is 1–0x7fffffff; the default value is 1. This option has an
           effect only for the balance-tlb and balance-alb modes.

       AdSelect=
           Specifies the 802.3ad aggregation selection logic to use. Possible
           values are "stable", "bandwidth" and "count".

       AdActorSystemPriority=
           Specifies the 802.3ad actor system priority. Takes a number in the
           range 1—65535.

       AdUserPortKey=
           Specifies the 802.3ad user defined portion of the port key. Takes a
           number in the range 0–1023.

       AdActorSystem=
           Specifies the 802.3ad system MAC address. This cannot be a null or
           multicast address.

       FailOverMACPolicy=
           Specifies whether the active-backup mode should set all slaves to the
           same MAC address at the time of enslavement or, when enabled, to
           perform special handling of the bond's MAC address in accordance with
           the selected policy. The default policy is none. Possible values are
           "none", "active" and "follow".

       ARPValidate=
           Specifies whether or not ARP probes and replies should be validated
           in any mode that supports ARP monitoring, or whether non-ARP traffic
           should be filtered (disregarded) for link monitoring purposes.
           Possible values are "none", "active", "backup" and "all".

       ARPIntervalSec=
           Specifies the ARP link monitoring frequency. A value of 0 disables
           ARP monitoring. The default value is 0, and the default unit seconds.

       ARPIPTargets=
           Specifies the IP addresses to use as ARP monitoring peers when
           ARPIntervalSec is greater than 0. These are the targets of the ARP
           request sent to determine the health of the link to the targets.
           Specify these values in IPv4 dotted decimal format. At least one IP
           address must be given for ARP monitoring to function. The maximum
           number of targets that can be specified is 16. The default value is
           no IP addresses.

       ARPAllTargets=
           Specifies the quantity of ARPIPTargets that must be reachable in
           order for the ARP monitor to consider a slave as being up. This
           option affects only active-backup mode for slaves with ARPValidate
           enabled. Possible values are "any" and "all".

       PrimaryReselectPolicy=
           Specifies the reselection policy for the primary slave. This affects
           how the primary slave is chosen to become the active slave when
           failure of the active slave or recovery of the primary slave occurs.
           This option is designed to prevent flip-flopping between the primary
           slave and other slaves. Possible values are "always", "better" and
           "failure".

       ResendIGMP=
           Specifies the number of IGMP membership reports to be issued after a
           failover event. One membership report is issued immediately after the
           failover, subsequent packets are sent in each 200ms interval. The
           valid range is 0–255. Defaults to 1. A value of 0 prevents the IGMP
           membership report from being issued in response to the failover
           event.

       PacketsPerSlave=
           Specify the number of packets to transmit through a slave before
           moving to the next one. When set to 0, then a slave is chosen at
           random. The valid range is 0–65535. Defaults to 1. This option only
           has effect when in balance-rr mode.

       GratuitousARP=
           Specify the number of peer notifications (gratuitous ARPs and
           unsolicited IPv6 Neighbor Advertisements) to be issued after a
           failover event. As soon as the link is up on the new slave, a peer
           notification is sent on the bonding device and each VLAN sub-device.
           This is repeated at each link monitor interval (ARPIntervalSec or
           MIIMonitorSec, whichever is active) if the number is greater than 1.
           The valid range is 0–255. The default value is 1. These options
           affect only the active-backup mode.

       AllSlavesActive=
           Takes a boolean. Specifies that duplicate frames (received on
           inactive ports) should be dropped when false, or delivered when true.
           Normally, bonding will drop duplicate frames (received on inactive
           ports), which is desirable for most users. But there are some times
           it is nice to allow duplicate frames to be delivered. The default
           value is false (drop duplicate frames received on inactive ports).

       DynamicTransmitLoadBalancing=
           Takes a boolean. Specifies if dynamic shuffling of flows is enabled.
           Applies only for balance-tlb mode. Defaults to unset.

       MinLinks=
           Specifies the minimum number of links that must be active before
           asserting carrier. The default value is 0.

       For more detail information see Linux Ethernet Bonding Driver HOWTO[1]

[XFRM] SECTION OPTIONS
       The [Xfrm] section accepts the following keys:

       InterfaceId=
           Sets the ID/key of the xfrm interface which needs to be associated
           with a SA/policy. Can be decimal or hexadecimal, valid range is
           0-0xffffffff, defaults to 0.

       Independent=
           Takes a boolean. If false (the default), the xfrm interface must have
           an underlying device which can be used for hardware offloading.

       For more detail information see Virtual XFRM Interfaces[16].

[VRF] SECTION OPTIONS
       The [VRF] section only applies for netdevs of kind "vrf" and accepts the
       following key:

       Table=
           The numeric routing table identifier. This setting is compulsory.

EXAMPLES
       Example 1. /etc/systemd/network/25-bridge.netdev

           [NetDev]
           Name=bridge0
           Kind=bridge

       Example 2. /etc/systemd/network/25-vlan1.netdev

           [Match]
           Virtualization=no

           [NetDev]
           Name=vlan1
           Kind=vlan

           [VLAN]
           Id=1

       Example 3. /etc/systemd/network/25-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/1-fou-tunnel.netdev

           [NetDev]
           Name=fou-tun
           Kind=fou

           [FooOverUDP]
           Port=5555
           Protocol=4


       Example 5. /etc/systemd/network/25-fou-ipip.netdev

           [NetDev]
           Name=ipip-tun
           Kind=ipip

           [Tunnel]
           Independent=yes
           Local=10.65.208.212
           Remote=10.65.208.211
           FooOverUDP=yes
           FOUDestinationPort=5555


       Example 6. /etc/systemd/network/25-tap.netdev

           [NetDev]
           Name=tap-test
           Kind=tap

           [Tap]
           MultiQueue=yes
           PacketInfo=yes

       Example 7. /etc/systemd/network/25-sit.netdev

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

           [Tunnel]
           Local=10.65.223.238
           Remote=10.65.223.239

       Example 8. /etc/systemd/network/25-6rd.netdev

           [NetDev]
           Name=6rd-tun
           Kind=sit
           MTUBytes=1480

           [Tunnel]
           Local=10.65.223.238
           IPv6RapidDeploymentPrefix=2602::/24

       Example 9. /etc/systemd/network/25-gre.netdev

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

           [Tunnel]
           Local=10.65.223.238
           Remote=10.65.223.239

       Example 10. /etc/systemd/network/25-ip6gre.netdev

           [NetDev]
           Name=ip6gre-tun
           Kind=ip6gre

           [Tunnel]
           Key=123

       Example 11. /etc/systemd/network/25-vti.netdev

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

           [Tunnel]
           Local=10.65.223.238
           Remote=10.65.223.239

       Example 12. /etc/systemd/network/25-veth.netdev

           [NetDev]
           Name=veth-test
           Kind=veth

           [Peer]
           Name=veth-peer

       Example 13. /etc/systemd/network/25-bond.netdev

           [NetDev]
           Name=bond1
           Kind=bond

           [Bond]
           Mode=802.3ad
           TransmitHashPolicy=layer3+4
           MIIMonitorSec=1s
           LACPTransmitRate=fast

       Example 14. /etc/systemd/network/25-dummy.netdev

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

       Example 15. /etc/systemd/network/25-vrf.netdev

       Create a VRF interface with table 42.

           [NetDev]
           Name=vrf-test
           Kind=vrf

           [VRF]
           Table=42

       Example 16. /etc/systemd/network/25-macvtap.netdev

       Create a MacVTap device.

           [NetDev]
           Name=macvtap-test
           Kind=macvtap


       Example 17. /etc/systemd/network/25-wireguard.netdev

           [NetDev]
           Name=wg0
           Kind=wireguard

           [WireGuard]
           PrivateKey=EEGlnEPYJV//kbvvIqxKkQwOiS+UENyPncC4bF46ong=
           ListenPort=51820

           [WireGuardPeer]
           PublicKey=RDf+LSpeEre7YEIKaxg+wbpsNV7du+ktR99uBEtIiCA=
           AllowedIPs=fd31:bf08:57cb::/48,192.168.26.0/24
           Endpoint=wireguard.example.com:51820

       Example 18. /etc/systemd/network/27-xfrm.netdev

           [NetDev]
           Name=xfrm0
           Kind=xfrm

           [Xfrm]
           Independent=yes

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

NOTES
        1. Linux Ethernet Bonding Driver HOWTO
           https://www.kernel.org/doc/Documentation/networking/bonding.txt

        2. RFC 2784
           https://tools.ietf.org/html/rfc2784

        3. IEEE 802.1Q
           http://www.ieee802.org/1/pages/802.1Q.html

        4. VRF
           https://www.kernel.org/doc/Documentation/networking/vrf.txt

        5. (DVOE)
           https://en.wikipedia.org/wiki/Distributed_Overlay_Virtual_Ethernet

        6. VXLAN Group Policy
           https://tools.ietf.org/html/draft-smith-vxlan-group-policy

        7. Generic Protocol Extension for VXLAN
           https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-07

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

        9. RFC 6437
           https://tools.ietf.org/html/rfc6437

       10. RFC 2460
           https://tools.ietf.org/html/rfc2460

       11. RFC 2473
           https://tools.ietf.org/html/rfc2473#section-4.1.1

       12. ip-xfrm — transform configuration
           http://man7.org/linux/man-pages/man8/ip-xfrm.8.html

       13. Foo over UDP
           https://lwn.net/Articles/614348

       14. IPv6 Rapid Deployment
           https://tools.ietf.org/html/rfc5569

       15. Generic UDP Encapsulation
           https://lwn.net/Articles/615044

       16. Virtual XFRM Interfaces
           https://lwn.net/Articles/757391



systemd 247                                                    SYSTEMD.NETDEV(5)