NAME¶
systemd.netdev - Virtual Network Device configuration
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 and
/usr/local/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 alphanumeric order, regardless of the directories in which they
live. However, files with identical filenames replace each other. It is
recommended that each filename is prefixed with a number smaller than
"70" (e.g. 10-vlan.netdev). Otherwise, .netdev files generated by
systemd-network-generator.service(8) may take precedence over user
configured files. 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 merged in the alphanumeric
order and parsed after the main file itself has been 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. Name
"gre0" should not be used, as the kernel creates a device with
this name when the corresponding kernel module is loaded. |
| gretap |
A Level 2 GRE tunnel over IPv4. Name "gretap0" should not be
used, as the kernel creates a device with this name when the corresponding
kernel module is loaded. |
| 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. Name "erspan0" should not be used, as
the kernel creates a device with this name when the corresponding kernel
module is loaded. |
| 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 a UDP
tunnel. |
| batadv |
B.A.T.M.A.N. Advanced[5] is a routing protocol for multi-hop
mobile ad-hoc networks which operates on layer 2. |
| ipoib |
An IP over Infiniband subinterface. |
| wlan |
A virtual wireless network (WLAN) interface. |
[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, the previously assigned value is cleared.
Added in version 211.
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, the previously assigned value is cleared.
Added in version 211.
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, the previously assigned value is
cleared.
Added in version 211.
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, the previously assigned value is cleared.
Added in version 237.
Credential=
Checks whether the specified credential was passed to the
systemd-udevd.service service. See
System and Service Credentials[6]
for details. When prefixed with an exclamation mark ("!"), the
result is negated. If an empty string is assigned, the previously assigned
value is cleared.
Added in version 252.
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, the previously assigned value is
cleared.
Added in version 211.
Firmware=
Checks whether the system is running on a machine with
the specified firmware. See
ConditionFirmware= in
systemd.unit(5) for details. When prefixed with an exclamation mark
("!"), the result is negated. If an empty string is assigned, the
previously assigned value is cleared.
Added in version 249.
[NETDEV] SECTION OPTIONS¶
The [NetDev] section accepts the following keys:
Description=
A free-form description of the netdev.
Added in version 215.
Name=
The interface name used when creating the netdev. This
setting is compulsory.
Added in version 211.
Kind=
The netdev kind. This setting is compulsory. See the
"Supported netdev kinds" section for the valid keys.
Added in version 211.
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.
Added in version 215.
MACAddress=
Specifies the MAC address to use for the device, or takes
the special value "none". When "none",
systemd-networkd does not request the MAC address for the device, and
the kernel will assign a random MAC address. For "tun",
"tap", or "l2tp" devices, the
MACAddress= setting
in the [NetDev] section is not supported and will be ignored. Please specify
it in the [Link] section of the corresponding
systemd.network(5) file.
If this option is not set, "vlan" device inherits the MAC address of
the master interface. For other kind of netdevs, if this option is not set,
then the MAC address is generated based on the interface name and the
machine-id(5).
Note, even if "none" is specified, systemd-udevd
will assign the persistent MAC address for the device, as 99-default.link
has MACAddressPolicy=persistent. So, it is also necessary to create a
custom .link file for the device, if the MAC address assignment is not
desired.
Added in version 215.
[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.
Added in version 227.
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.
Added in version 227.
ForwardDelaySec=
ForwardDelaySec specifies the number of seconds spent in
each of the Listening and Learning states before the Forwarding state is
entered.
Added in version 227.
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.
Added in version 232.
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.
Added in version 232.
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).
Added in version 235.
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.
Added in version 232.
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.
Added in version 230.
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.
Added in version 230.
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.
Added in version 231.
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.
Added in version 246.
STP=
Takes a boolean. This enables the bridge's Spanning Tree
Protocol (STP). When unset, the kernel's default will be used.
Added in version 232.
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.
Added in version 243.
FDBMaxLearned=
Specifies the maximum number of learned Ethernet
addresses for the bridge. When the limit is reached, no more addresses are
learned. When unset, the kernel's default will be used. 0 disables the limit.
Added in version 257.
[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.
Added in version 211.
Protocol=
Allows setting the protocol used for the VLAN interface.
Takes "802.1q" or, "802.1ad", and defaults to unset and
kernel's default is used.
Added in version 248.
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.
Added in version 234.
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.
Added in version 234.
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.
Added in version 234.
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.
Added in version 234.
EgressQOSMaps=, IngressQOSMaps=
Defines a mapping of Linux internal packet priority
(
SO_PRIORITY) to VLAN header PCP field for outgoing and incoming
frames, respectively. Takes a whitespace-separated list of integer pairs,
where each integer must be in the range 1...4294967294, in the format
"from"-"to", e.g., "21-7 45-5". Note that
"from" must be greater than or equal to "to". When unset,
the kernel's default will be used.
Added in version 248.
[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".
Added in version 211.
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.
Added in version 246.
BroadcastMulticastQueueLength=
Specifies the length of the receive queue for
broadcast/multicast packets. An unsigned integer in the range 0...4294967294.
Defaults to unset.
Added in version 248.
BroadcastQueueThreshold=
Controls the threshold for broadcast queueing of the
macvlan device. Takes the special value "no", or an integer in the
range 0...2147483647. When "no" is specified, the broadcast queueing
is disabled altogether. When an integer is specified, a multicast address will
be queued as broadcast if the number of devices using it is greater than the
given value. Defaults to unset, and the kernel default will be used.
Added in version 256.
[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".
Added in version 219.
Flags=
The IPVLAN flags to use. The supported options are
"bridge","private" and "vepa".
Added in version 237.
[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.
Added in version 243.
Remote=
Configures destination IP address.
Added in version 233.
Local=
Configures local IP address. It must be an address on the
underlying interface of the VXLAN interface, or one of the special values
"ipv4_link_local", "ipv6_link_local", "dhcp4",
"dhcp6", and "slaac". If one of the special values is
specified, an address which matches the corresponding type on the underlying
interface will be used. Defaults to unset.
Added in version 233.
Group=
Configures VXLAN multicast group IP address. All members
of a VXLAN must use the same multicast group address.
Added in version 243.
TOS=
The Type Of Service byte value for a vxlan interface.
Added in version 215.
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.
Added in version 215.
MacLearning=
Takes a boolean. When true, enables dynamic MAC learning
to discover remote MAC addresses.
Added in version 215.
FDBAgeingSec=
The lifetime of Forwarding Database entry learnt by the
kernel, in seconds.
Added in version 218.
MaximumFDBEntries=
Configures maximum number of FDB entries.
Added in version 228.
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 (DOVE)[7] clients. Defaults to
false.
Added in version 233.
L2MissNotification=
Takes a boolean. When true, enables netlink LLADDR miss
notifications.
Added in version 218.
L3MissNotification=
Takes a boolean. When true, enables netlink IP address
miss notifications.
Added in version 218.
RouteShortCircuit=
Takes a boolean. When true, route short circuiting is
turned on.
Added in version 218.
UDPChecksum=
Takes a boolean. When true, transmitting UDP checksums
when doing VXLAN/IPv4 is turned on.
Added in version 220.
UDP6ZeroChecksumTx=
Takes a boolean. When true, sending zero checksums in
VXLAN/IPv6 is turned on.
Added in version 220.
UDP6ZeroChecksumRx=
Takes a boolean. When true, receiving zero checksums in
VXLAN/IPv6 is turned on.
Added in version 220.
RemoteChecksumTx=
Takes a boolean. When true, remote transmit checksum
offload of VXLAN is turned on.
Added in version 232.
RemoteChecksumRx=
Takes a boolean. When true, remote receive checksum
offload in VXLAN is turned on.
Added in version 232.
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[8]
document. Defaults to false.
Added in version 224.
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[9] document. If destination port
is not specified and Generic Protocol Extension is set then default port of
4790 is used. Defaults to false.
Added in version 243.
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.
Added in version 229.
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.
Added in version 229.
FlowLabel=
Specifies the flow label to use in outgoing packets. The
valid range is 0-1048575.
Added in version 234.
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.
Added in version 243.
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 VXLAN interface using
VXLAN= is required for the VXLAN to be created.
Added in version 247.
[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.
Added in version 234.
Remote=
Specifies the unicast destination IP address to use in
outgoing packets.
Added in version 234.
TOS=
Specifies the TOS value to use in outgoing packets. Takes
a number between 1 and 255.
Added in version 234.
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.
Added in version 234.
UDPChecksum=
Takes a boolean. When true, specifies that UDP checksum
is calculated for transmitted packets over IPv4.
Added in version 234.
UDP6ZeroChecksumTx=
Takes a boolean. When true, skip UDP checksum calculation
for transmitted packets over IPv6.
Added in version 234.
UDP6ZeroChecksumRx=
Takes a boolean. When true, allows incoming UDP packets
over IPv6 with zero checksum field.
Added in version 234.
DestinationPort=
Specifies destination port. Defaults to 6081. If not set
or assigned the empty string, the default port of 6081 is used.
Added in version 234.
FlowLabel=
Specifies the flow label to use in outgoing packets.
Added in version 234.
IPDoNotFragment=
Accepts the same key as in [VXLAN] section.
Added in version 243.
InheritInnerProtocol=
Takes a boolean. When true, inner Layer 3 protocol is set
as Protocol Type in the GENEVE header instead of Ethernet. Defaults to false.
Added in version 254.
[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.
Added in version 247.
EtherType=
Specifies the L3 protocol. Takes one of "ipv4",
"ipv6", "mpls-uc" or "mpls-mc". This is
mandatory.
Added in version 247.
MinSourcePort=
Specifies the lowest value of the UDP tunnel source UDP
port (in range 1...65535). Defaults to unset.
Added in version 257.
[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.
Added in version 242.
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.
Added in version 242.
Remote=
Specifies the IP address of the remote peer. This setting
is compulsory.
Added in version 242.
Local=
Specifies the IP address of a local interface. Takes an
IP address, or the special values "auto", "static", or
"dynamic". Optionally a name of a local interface can be specified
after "@", e.g. "192.168.0.1@eth0" or
"auto@eth0". When an address is specified, then a local or specified
interface must have the address, and the remote address must be accessible
through the local address. If "auto", then one of the addresses on a
local or specified interface which is accessible to the remote address will be
used. Similarly, if "static" or "dynamic" is set, then one
of the static or dynamic addresses will be used. Defaults to "auto".
Added in version 242.
EncapsulationType=
Specifies the encapsulation type of the tunnel. Takes one
of "udp" or "ip".
Added in version 242.
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.
Added in version 242.
UDPDestinationPort=
Specifies destination port. When UDP encapsulation is
selected it's mandatory. Ignored when IP encapsulation is selected.
Added in version 245.
UDPChecksum=
Takes a boolean. When true, specifies that UDP checksum
is calculated for transmitted packets over IPv4.
Added in version 242.
UDP6ZeroChecksumTx=
Takes a boolean. When true, skip UDP checksum calculation
for transmitted packets over IPv6.
Added in version 242.
UDP6ZeroChecksumRx=
Takes a boolean. When true, allows incoming UDP packets
over IPv6 with zero checksum field.
Added in version 242.
[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.
Added in version 242.
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.
Added in version 242.
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.
Added in version 242.
Layer2SpecificHeader=
Specifies layer2specific header type of the session. One
of "none" or "default". Defaults to "default".
Added in version 242.
[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.
Added in version 243.
Encrypt=
Takes a boolean. When true, enable encryption. Defaults
to unset.
Added in version 243.
[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.
Added in version 243.
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.
Added in version 243.
[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.
Added in version 243.
KeyId=
Specifies the identification for the key. Takes a number
between 0-255. This option is compulsory, and is not set by default.
Added in version 243.
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".
Added in version 243.
KeyFile=
Takes an 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.
Added in version 243.
Activate=
Takes a boolean. If enabled, then the security
association is activated. Defaults to unset.
Added in version 243.
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.
Added in version 243.
[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.
Added in version 243.
MACAddress=
Accepts the same key as in [MACsecReceiveChannel]
section.
Added in version 243.
PacketNumber=
Accepts the same key as in [MACsecTransmitAssociation]
section.
Added in version 243.
KeyId=
Accepts the same key as in [MACsecTransmitAssociation]
section.
Added in version 243.
Key=
Accepts the same key as in [MACsecTransmitAssociation]
section.
Added in version 243.
KeyFile=
Accepts the same key as in [MACsecTransmitAssociation]
section.
Added in version 243.
Activate=
Accepts the same key as in [MACsecTransmitAssociation]
section.
Added in version 243.
[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:
External=
Takes a boolean value. When true, then the tunnel is
externally controlled, which is also known as collect metadata mode, and most
settings below like
Local= or
Remote= are ignored. This implies
Independent=. Defaults to false.
Added in version 251.
Local=
A static local address for tunneled packets. It must be
an address on another interface of this host, or one of the special values
"any", "ipv4_link_local", "ipv6_link_local",
"dhcp4", "dhcp6", and "slaac". If one of the
special values except for "any" is specified, an address which
matches the corresponding type on the underlying interface will be used.
Defaults to "any".
Added in version 215.
Remote=
The remote endpoint of the tunnel. Takes an IP address or
the special value "any".
Added in version 215.
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[10] document.
Added in version 215.
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.
Added in version 215.
DiscoverPathMTU=
Takes a boolean. When true, enables Path MTU Discovery on
the tunnel. When
IgnoreDontFragment= is enabled, defaults to false.
Otherwise, defaults to true.
Added in version 215.
IgnoreDontFragment=
Takes a boolean. When true, enables IPv4 Don't Fragment
(DF) suppression on the tunnel. Defaults to false. Note that if
IgnoreDontFragment= is set to true,
DiscoverPathMTU= cannot be
set to true. Only applicable to GRE, GRETAP, and ERSPAN tunnels.
Added in version 254.
IPv6FlowLabel=
Configures the 20-bit flow label (see
RFC
6437[11]) field in the IPv6 header (see
RFC 2460[12]), 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.
Added in version 223.
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".
Added in version 223.
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[13]). The valid
range is 0...255 and "none". Defaults to 4.
Added in version 226.
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[14] for details. It is only
used for VTI/VTI6, GRE, GRETAP, and ERSPAN tunnels.
Added in version 231.
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.
Added in version 231.
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.
Added in version 231.
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.
Added in version 219.
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".
Added in version 235.
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".
Added in version 243.
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.
Added in version 237.
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[15]
Added in version 240.
FOUDestinationPort=
This setting specifies the UDP destination port for
encapsulation. This field is mandatory when
FooOverUDP=yes, and is not
set by default.
Added in version 240.
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.
Added in version 240.
Encapsulation=
Accepts the same key as in the [FooOverUDP] section.
Added in version 240.
IPv6RapidDeploymentPrefix=
Reconfigure the tunnel for
IPv6 Rapid
Deployment[16], also known as 6rd. The value is an ISP-specific IPv6
prefix with a non-zero length. Only applicable to SIT tunnels.
Added in version 240.
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.
Added in version 240.
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.
Added in version 240.
ERSPANVersion=
Specifies the ERSPAN version number. Takes 0 for version
0 (a.k.a. type I), 1 for version 1 (a.k.a. type II), or 2 for version 2
(a.k.a. type III). Defaults to 1.
Added in version 252.
ERSPANIndex=
Specifies the ERSPAN v1 index field for the interface.
Takes an integer in the range 0...1048575, which is associated with the ERSPAN
traffic's source port and direction. Only used when
ERSPANVersion=1.
Defaults to 0.
Added in version 240.
ERSPANDirection=
Specifies the ERSPAN v2 mirrored traffic's direction.
Takes "ingress" or "egress". Only used when
ERSPANVersion=2. Defaults to "ingress".
Added in version 252.
ERSPANHardwareId=
Specifies an unique identifier of the ERSPAN v2 engine.
Takes an integer in the range 0...63. Only used when
ERSPANVersion=2.
Defaults to 0.
Added in version 252.
[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[17]. Defaults to "FooOverUDP".
Added in version 240.
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.
Added in version 240.
PeerPort=
Specifies the peer port number. Defaults to unset. Note
that when peer port is set "Peer=" address is mandatory.
Added in version 243.
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.
Added in version 240.
Peer=
Configures peer IP address. Note that when peer address
is set "PeerPort=" is mandatory.
Added in version 243.
Local=
Configures local IP address.
Added in version 243.
[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.
Added in version 215.
MACAddress=
The peer MACAddress, if not set, it is generated in the
same way as the MAC address of the main interface.
Added in version 215.
[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.
Added in version 236.
[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".
Added in version 215.
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".
Added in version 215.
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".
Added in version 223.
User=
User to grant access to the /dev/net/tun device.
Added in version 215.
Group=
Group to grant access to the /dev/net/tun device.
Added in version 215.
KeepCarrier=
Takes a boolean. If enabled, to make the interface
maintain its carrier status, the file descriptor of the interface is kept
open. This may be useful to keep the interface in running state, for example
while the backing process is temporarily shutdown. Defaults to "no".
Added in version 252.
[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)). Specially,
if the specified key is prefixed with "@", it is interpreted as the
name of the credential from which the actual key shall be read.
systemd-networkd.service automatically imports credentials matching
"network.wireguard.*". For more details on credentials, refer to
systemd.exec(5). A private key is mandatory to use WireGuard. If not
set, the credential "network.wireguard.private.
netdev" is
used if exists. I.e. for 50-foobar.netdev,
"network.wireguard.private.50-foobar" is tried.
Note that because this information is secret, it's strongly
recommended to use an (encrypted) credential. Alternatively, you may want to
set the permissions of the .netdev file to be owned by
"root:systemd-network" with a "0640" file mode.
Added in version 237.
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.
Added in version 242.
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".
Added in version 237.
FirewallMark=
Sets a firewall mark on outgoing WireGuard packets from
this interface. Takes a number between 1 and 4294967295.
Added in version 243.
RouteTable=
The table identifier for the routes to the addresses
specified in the
AllowedIPs=. Takes a negative boolean value, one of
the predefined names "default", "main", and
"local", names defined in
RouteTable= in
networkd.conf(5), or a number in the range 1...4294967295. When
"off" the routes to the addresses specified in the
AllowedIPs= setting will not be configured. Defaults to false. This
setting will be ignored when the same setting is specified in the
[WireGuardPeer] section.
Added in version 250.
RouteMetric=
The priority of the routes to the addresses specified in
the
AllowedIPs=. Takes an integer in the range 0...4294967295. Defaults
to 0 for IPv4 addresses, and 1024 for IPv6 addresses. This setting will be
ignored when the same setting is specified in the [WireGuardPeer] section.
Added in version 250.
[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 honors the
"@" prefix in the same way as the
PrivateKey= setting of the
[WireGuard] section. This option is mandatory for this section.
Added in version 237.
PublicKeyFile=
Takes an absolute path to a file which contains the
Base64 encoded public key for the peer. When this option is specified, then
PublicKey= will be 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.
Added in version 257.
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. This option honors the
"@" prefix in the same way as the
PrivateKey= setting of the
[WireGuard] section.
Note that because this information is secret, it's strongly
recommended to use an (encrypted) credential. Alternatively, you may want to
set the permissions of the .netdev file to be owned by
"root:systemd-network" with a "0640" file mode.
Added in version 237.
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.
Added in version 242.
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. This setting can be
specified multiple times. If an empty string is assigned, then the all
previous assignments are cleared.
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, i.e. the packets that pass through the tunnel itself.
To cause packets to be sent via the tunnel in the first place, an
appropriate route needs to be added as well — either in the
"[Routes]" section on the ".network" matching the
wireguard interface, or externally to systemd-networkd.
Added in version 237.
Endpoint=
Sets an endpoint IP address or hostname, followed by a
colon, and then a port number. IPv6 address must be in the square brackets.
For example, "111.222.333.444:51820" for IPv4 and
"[1111:2222::3333]:51820" for IPv6 address. 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.
This option honors the "@" prefix in the same way as the
PrivateKey= setting of the [WireGuard] section.
Added in version 237.
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.
Added in version 237.
RouteTable=
The table identifier for the routes to the addresses
specified in the
AllowedIPs=. Takes a negative boolean value, one of
the predefined names "default", "main", and
"local", names defined in
RouteTable= in
networkd.conf(5), or a number in the range 1...4294967295. Defaults to
unset, and the value specified in the same setting in the [WireGuard] section
will be used.
Added in version 250.
RouteMetric=
The priority of the routes to the addresses specified in
the
AllowedIPs=. Takes an integer in the range 0...4294967295. Defaults
to unset, and the value specified in the same setting in the [WireGuard]
section will be used.
Added in version 250.
[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".
Added in version 216.
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".
Added in version 216.
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".
Added in version 216.
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.
Added in version 216.
PeerNotifyDelaySec=
Specifies the number of seconds the delay between each
peer notification (gratuitous ARP and unsolicited IPv6 Neighbor Advertisement)
when they are issued after a failover event. This delay should be a multiple
of the MII link monitor interval (miimon). The valid range is 0...300s. The
default value is 0, which means to match the value of the
MIIMonitorSec=.
Added in version 256.
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.
Added in version 216.
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.
Added in version 216.
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.
Added in version 220.
AdSelect=
Specifies the 802.3ad aggregation selection logic to use.
Possible values are "stable", "bandwidth" and
"count".
Added in version 220.
AdActorSystemPriority=
Specifies the 802.3ad actor system priority. Takes a
number in the range 1...65535.
Added in version 240.
AdUserPortKey=
Specifies the 802.3ad user defined portion of the port
key. Takes a number in the range 0...1023.
Added in version 240.
AdActorSystem=
Specifies the 802.3ad system MAC address. This cannot be
a null or multicast address.
Added in version 240.
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".
Added in version 220.
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".
Added in version 220.
ARPIntervalSec=
Specifies the ARP link monitoring frequency. A value of 0
disables ARP monitoring. The default value is 0, and the default unit seconds.
Added in version 220.
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.
Added in version 220.
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".
Added in version 220.
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".
Added in version 220.
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.
Added in version 220.
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.
Added in version 220.
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.
Added in version 220.
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).
Added in version 220.
DynamicTransmitLoadBalancing=
Takes a boolean. Specifies if dynamic shuffling of flows
is enabled. Applies only for balance-tlb mode. Defaults to unset.
Added in version 240.
MinLinks=
Specifies the minimum number of links that must be active
before asserting carrier. The default value is 0.
Added in version 220.
ARPMissedMax=
Specify the maximum number of arp interval monitor cycle
for missed ARP replies. If this number is exceeded, link is reported as down.
Defaults to unset.
Added in version 256.
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
1-0xffffffff. This is mandatory.
Added in version 243.
Independent=
Takes a boolean. If false (the default), the xfrm
interface must have an underlying device which can be used for hardware
offloading.
Added in version 243.
For more detail information see Virtual XFRM
Interfaces[18].
[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.
Added in version 243.
[BATMANADVANCED] SECTION OPTIONS¶
The [BatmanAdvanced] section only applies for netdevs of kind
"batadv" and accepts the following keys:
GatewayMode=
Takes one of "off", "server", or
"client". A batman-adv node can either run in server mode (sharing
its internet connection with the mesh) or in client mode (searching for the
most suitable internet connection in the mesh) or having the gateway support
turned off entirely (which is the default setting).
Added in version 248.
Aggregation=
Takes a boolean value. Enables or disables aggregation of
originator messages. Defaults to true.
Added in version 248.
BridgeLoopAvoidance=
Takes a boolean value. Enables or disables avoidance of
loops on bridges. Defaults to true.
Added in version 248.
DistributedArpTable=
Takes a boolean value. Enables or disables the
distributed ARP table. Defaults to true.
Added in version 248.
Fragmentation=
Takes a boolean value. Enables or disables fragmentation.
Defaults to true.
Added in version 248.
HopPenalty=
The hop penalty setting allows one to modify
batctl(8) preference for multihop routes vs. short routes. This integer
value is applied to the TQ (Transmit Quality) of each forwarded OGM
(Originator Message), thereby propagating the cost of an extra hop (the packet
has to be received and retransmitted which costs airtime). A higher hop
penalty will make it more unlikely that other nodes will choose this node as
intermediate hop towards any given destination. The default hop penalty of
'15' is a reasonable value for most setups and probably does not need to be
changed. However, mobile nodes could choose a value of 255 (maximum value) to
avoid being chosen as a router by other nodes. The minimum value is 0.
Added in version 248.
OriginatorIntervalSec=
The value specifies the interval in seconds, unless
another time unit is specified in which batman-adv floods the network with its
protocol information. See
systemd.time(7) for more information.
Added in version 248.
GatewayBandwidthDown=
If the node is a server, this parameter is used to inform
other nodes in the network about this node's internet connection download
bandwidth in bits per second. Just enter any number suffixed with K, M, G or T
(base 1000) and the batman-adv module will propagate the entered value in the
mesh.
Added in version 248.
GatewayBandwidthUp=
If the node is a server, this parameter is used to inform
other nodes in the network about this node's internet connection upload
bandwidth in bits per second. Just enter any number suffixed with K, M, G or T
(base 1000) and the batman-adv module will propagate the entered value in the
mesh.
Added in version 248.
RoutingAlgorithm=
This can be either "batman-v" or
"batman-iv" and describes which routing_algo of
batctl(8) to
use. The algorithm cannot be changed after interface creation. Defaults to
"batman-v".
Added in version 248.
[IPOIB] SECTION OPTIONS¶
The [IPoIB] section only applies for netdevs of kind
"ipoib" and accepts the following keys:
PartitionKey=
Takes an integer in the range 1...0xffff, except for
0x8000. Defaults to unset, and the kernel's default is used.
Added in version 250.
Mode=
Takes one of the special values "datagram" or
"connected". Defaults to unset, and the kernel's default is used.
When "datagram", the Infiniband unreliable datagram (UD)
transport is used, and so the interface MTU is equal to the IB L2 MTU minus
the IPoIB encapsulation header (4 bytes). For example, in a typical IB
fabric with a 2K MTU, the IPoIB MTU will be 2048 - 4 = 2044 bytes.
When "connected", the Infiniband reliable connected (RC)
transport is used. Connected mode takes advantage of the connected nature of
the IB transport and allows an MTU up to the maximal IP packet size of 64K,
which reduces the number of IP packets needed for handling large UDP
datagrams, TCP segments, etc and increases the performance for large
messages.
Added in version 250.
IgnoreUserspaceMulticastGroup=
Takes an boolean value. When true, the kernel ignores
multicast groups handled by userspace. Defaults to unset, and the kernel's
default is used.
Added in version 250.
[WLAN] SECTION OPTIONS¶
The [WLAN] section only applies to WLAN interfaces, and accepts
the following keys:
PhysicalDevice=
Specifies the name or index of the physical WLAN device
(e.g. "0" or "phy0"). The list of the physical WLAN
devices that exist on the host can be obtained by
iw phy command. This
option is mandatory.
Added in version 251.
Type=
Specifies the type of the interface. Takes one of the
"ad-hoc", "station", "ap", "ap-vlan",
"wds", "monitor", "mesh-point",
"p2p-client", "p2p-go", "p2p-device",
"ocb", and "nan". This option is mandatory.
Added in version 251.
WDS=
Enables the Wireless Distribution System (WDS) mode on
the interface. The mode is also known as the "4 address mode". Takes
a boolean value. Defaults to unset, and the kernel's default will be used.
Added in version 251.
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
NOTES¶
- 1.
- Linux Ethernet Bonding Driver HOWTO
- 2.
- RFC 2784
- 3.
- IEEE 802.1Q
- 4.
- VRF
- 5.
- B.A.T.M.A.N. Advanced
- 6.
- System and Service Credentials
- 7.
- Distributed Overlay Virtual Ethernet (DOVE)
- 8.
- VXLAN Group Policy
- 9.
- Generic Protocol Extension for VXLAN
- 10.
- Type of Service in the Internet Protocol Suite
- 11.
- RFC 6437
- 12.
- RFC 2460
- 13.
- RFC 2473
- 14.
- ip-xfrm — transform configuration
- 15.
- Foo over UDP
- 16.
- IPv6 Rapid Deployment
- 17.
- Generic UDP Encapsulation
- 18.
- Virtual XFRM Interfaces
