ip-link(8) — Linux manual page

NAME \| SYNOPSIS \| DESCRIPTION \| EXAMPLES \| SEE ALSO \| AUTHOR \| COLOPHON

IP-LINK(8)                        Linux                        IP-LINK(8)

NAME top

       ip-link - network device configuration

SYNOPSIS top

       ip link  { COMMAND | help }

       ip link add [ link DEVICE ] [ name ] NAME
               [ txqueuelen PACKETS ]
               [ address LLADDR ] [ broadcast LLADDR ]
               [ mtu MTU ] [ index IDX ]
               [ numtxqueues QUEUE_COUNT ] [ numrxqueues QUEUE_COUNT ]
               [ gso_max_size BYTES ] [ gso_ipv4_max_size BYTES ] [
               gso_max_segs SEGMENTS ]
               [ gro_max_size BYTES ] [ gro_ipv4_max_size BYTES ]
               [ netns { PID | NETNSNAME | NETNSFILE } ]
               type TYPE [ ARGS ]

       ip link delete { DEVICE | group GROUP } type TYPE [ ARGS ]

       ip link set { DEVICE | group GROUP }
               [ { up | down } ]
               [ type ETYPE TYPE_ARGS ]
               [ arp { on | off } ]
               [ dynamic { on | off } ]
               [ multicast { on | off } ]
               [ allmulticast { on | off } ]
               [ promisc { on | off } ]
               [ protodown { on | off } ]
               [ protodown_reason PREASON { on | off } ]
               [ trailers { on | off } ]
               [ txqueuelen PACKETS ]
               [ gso_max_size BYTES ] [ gso_ipv4_max_size BYTES ] [
               gso_max_segs SEGMENTS ]
               [ gro_max_size BYTES ] [ gro_ipv4_max_size BYTES ]
               [ name NEWNAME ]
               [ address LLADDR ]
               [ broadcast LLADDR ]
               [ mtu MTU ]
               [ netns { PID | NETNSNAME | NETNSFILE } ]
               [ link-netnsid ID ]
               [ alias NAME ]
               [ vf NUM [ mac LLADDR ]
                        [ VFVLAN-LIST ]
                        [ rate TXRATE ]
                        [ max_tx_rate TXRATE ]
                        [ min_tx_rate TXRATE ]
                        [ spoofchk { on | off } ]
                        [ query_rss { on | off } ]
                        [ state { auto | enable | disable } ]
                        [ trust { on | off } ]
                        [ node_guid eui64 ]
                        [ port_guid eui64 ] ]
               [ { xdp | xdpgeneric | xdpdrv | xdpoffload } { off |
                       object FILE [ { section | program } NAME ] [
                       verbose ] |
                       pinned FILE } ]
               [ master DEVICE ]
               [ nomaster ]
               [ vrf NAME ]
               [ addrgenmode { eui64 | none | stable_secret | random } ]
               [ macaddr [ MACADDR ]
                         [ { flush | add | del } MACADDR ]
                         [ set MACADDR ] ]

                 ip link show [ DEVICE | group GROUP ] [ up ] [ master
                         DEVICE ] [ type ETYPE ] [ vrf NAME ] [ nomaster
                         ]

                 ip link xstats type TYPE [ ARGS ]

                 ip link afstats [ dev DEVICE ]

                 ip link help [ TYPE ]

                 TYPE := [ amt | bareudp | bond | bridge | can | dsa |
                         dummy | erspan | geneve | gre | gretap | gtp |
                         hsr | ifb | ip6erspan | ip6gre | ip6gretap |
                         ip6tnl | ipip | ipoib | ipvlan | ipvtap | lowpan
                         | macsec | macvlan | macvtap | netdevsim | nlmon
                         | rmnet | sit | vcan | veth | virt_wifi | vlan |
                         vrf | vti | vxcan | vxlan | xfrm ]

                 ETYPE := [ TYPE | bridge_slave | bond_slave ]

                 VFVLAN-LIST := [ VFVLAN-LIST ] VFVLAN

                 VFVLAN := [ vlan VLANID [ qos VLAN-QOS ] [ proto VLAN-
                         PROTO ] ]

         ip link property add dev DEVICE [ altname NAME .. ]

         ip link property del dev DEVICE [ altname NAME .. ]

DESCRIPTION top

ip link add - add virtual link
link DEVICE
specifies the physical device to act operate on.

NAME specifies the name of the new virtual device.

TYPE specifies the type of the new device.

Link types:

amt - Automatic Multicast Tunneling (AMT)

bareudp - Bare UDP L3 encapsulation support

bond - Bonding device

bridge - Ethernet Bridge device

can - Controller Area Network

dsa - Distributed Switch Architecture

dummy - Dummy network interface

erspan - Encapsulated Remote SPAN over GRE and IPv4

geneve - GEneric NEtwork Virtualization
Encapsulation

gre - Virtual tunnel interface GRE over IPv4

gretap - Virtual L2 tunnel interface GRE over IPv4

gtp - GPRS Tunneling Protocol

hsr - High-availability Seamless Redundancy device

ifb - Intermediate Functional Block device

ip6erspan - Encapsulated Remote SPAN over GRE and
IPv6

ip6gre - Virtual tunnel interface GRE over IPv6

ip6gretap - Virtual L2 tunnel interface GRE over
IPv6

ip6tnl - Virtual tunnel interface IPv4|IPv6 over
IPv6

ipip - Virtual tunnel interface IPv4 over IPv4

ipoib - IP over Infiniband device

ipvlan - Interface for L3 (IPv6/IPv4) based VLANs

ipvtap - Interface for L3 (IPv6/IPv4) based VLANs
and TAP

lowpan - Interface for 6LoWPAN (IPv6) over IEEE
802.15.4 / Bluetooth

macsec - Interface for IEEE 802.1AE MAC Security
(MACsec)

macvlan - Virtual interface base on link layer
address (MAC)

macvtap - Virtual interface based on link layer
address (MAC) and TAP.

netdevsim - Interface for netdev API tests

nlmon - Netlink monitoring device

rmnet - Qualcomm rmnet device

sit - Virtual tunnel interface IPv6 over IPv4

vcan - Virtual Controller Area Network interface

veth - Virtual ethernet interface

virt_wifi - rtnetlink wifi simulation device

vlan - 802.1q tagged virtual LAN interface

vrf - Interface for L3 VRF domains

vti - Virtual tunnel interface

vxcan - Virtual Controller Area Network tunnel
interface

vxlan - Virtual eXtended LAN

xfrm - Virtual xfrm interface

numtxqueues QUEUE_COUNT
specifies the number of transmit queues for new device.

numrxqueues QUEUE_COUNT
specifies the number of receive queues for new device.

gso_max_size BYTES
specifies the recommended maximum size of a Generic Segment
Offload packet the new device should accept. This is also
used to enable BIG TCP for IPv6 on this device when the
size is greater than 65536.

gso_ipv4_max_size BYTES
specifies the recommended maximum size of a IPv4 Generic
Segment Offload packet the new device should accept. This
is especially used to enable BIG TCP for IPv4 on this
device by setting to a size greater than 65536.

gso_max_segs SEGMENTS
specifies the recommended maximum number of a Generic
Segment Offload segments the new device should accept.

gro_max_size BYTES
specifies the maximum size of a packet built by GRO stack
on this device. This is also used for BIG TCP to allow the
size of a merged IPv6 GSO packet on this device greater
than 65536.

gro_ipv4_max_size BYTES
specifies the maximum size of a IPv4 packet built by GRO
stack on this device. This is especially used for BIG TCP
to allow the size of a merged IPv4 GSO packet on this
device greater than 65536.

index IDX
specifies the desired index of the new virtual device. The
link creation fails, if the index is busy.

netns { PID | NETNSNAME | NETNSFILE }
create the device in the network namespace associated with
process PID or the name NETNSNAME or the file NETNSFILE.

VLAN Type Support
For a link of type VLAN the following additional arguments
are supported:

ip link add link DEVICE name NAME type vlan [ protocol
VLAN_PROTO ] id VLANID [ reorder_hdr { on | off } ] [ gvrp
{ on | off } ] [ mvrp { on | off } ] [ loose_binding { on |
off } ] [ bridge_binding { on | off } ] [ ingress-qos-map
QOS-MAP ] [ egress-qos-map QOS-MAP ]

protocol VLAN_PROTO - either 802.1Q or 802.1ad.

id VLANID - specifies the VLAN Identifier to use.
Note that numbers with a leading " 0 " or " 0x "
are interpreted as octal or hexadecimal,
respectively.

reorder_hdr { on | off } - specifies whether
ethernet headers are reordered or not (default is
on).

If reorder_hdr is on then VLAN header will be
not inserted immediately but only before
passing to the physical device (if this device
does not support VLAN offloading), the similar
on the RX direction - by default the packet
will be untagged before being received by VLAN
device. Reordering allows one to accelerate
tagging on egress and to hide VLAN header on
ingress so the packet looks like regular
Ethernet packet, at the same time it might be
confusing for packet capture as the VLAN header
does not exist within the packet.

VLAN offloading can be checked by ethtool(8):

ethtool -k <phy_dev> | grep tx-vlan-offload

where <phy_dev> is the physical device to which
VLAN device is bound.

gvrp { on | off } - specifies whether this VLAN
should be registered using GARP VLAN Registration
Protocol.

mvrp { on | off } - specifies whether this VLAN
should be registered using Multiple VLAN
Registration Protocol.

loose_binding { on | off } - specifies whether the
VLAN device state is bound to the physical device
state.

bridge_binding { on | off } - specifies whether the
VLAN device link state tracks the state of bridge
ports that are members of the VLAN.

ingress-qos-map QOS-MAP - defines a mapping of VLAN
header prio field to the Linux internal packet
priority on incoming frames. The format is FROM:TO
with multiple mappings separated by spaces.

egress-qos-map QOS-MAP - defines a mapping of Linux
internal packet priority to VLAN header prio field
but for outgoing frames. The format is the same as
for ingress-qos-map.

Linux packet priority can be set by
iptables(8):

iptables -t mangle -A POSTROUTING [...] -j
CLASSIFY --set-class 0:4

and this "4" priority can be used in the egress
qos mapping to set VLAN prio "5":

ip link set veth0.10 type vlan egress 4:5

VXLAN Type Support
For a link of type VXLAN the following additional arguments
are supported:

ip link add DEVICE type vxlan id VNI [ dev PHYS_DEV ] [ {
group | remote } IPADDR ] [ local { IPADDR | any } ] [ ttl
TTL ] [ tos TOS ] [ df DF ] [ flowlabel FLOWLABEL ] [
dstport PORT ] [ srcport MIN MAX ] [ [no]learning ] [
[no]proxy ] [ [no]rsc ] [ [no]l2miss ] [ [no]l3miss ] [
[no]udpcsum ] [ [no]udp6zerocsumtx ] [ [no]udp6zerocsumrx ]
[ [no]localbypass ] [ ageing SECONDS ] [ maxaddress NUMBER
] [ [no]external ] [ gbp ] [ gpe ] [ [no]vnifilter ]

id VNI - specifies the VXLAN Network Identifier (or
VXLAN Segment Identifier) to use.

dev PHYS_DEV - specifies the physical device to use
for tunnel endpoint communication.

group IPADDR - specifies the multicast IP address
to join. This parameter cannot be specified with
the remote parameter.

remote IPADDR - specifies the unicast destination
IP address to use in outgoing packets when the
destination link layer address is not known in the
VXLAN device forwarding database. This parameter
cannot be specified with the group parameter.

local IPADDR - specifies the source IP address to
use in outgoing packets.

ttl TTL - specifies the TTL value to use in
outgoing packets.

tos TOS - specifies the TOS value to use in
outgoing packets.

df DF - specifies the usage of the Don't Fragment
flag (DF) bit in outgoing packets with IPv4
headers. The value inherit causes the bit to be
copied from the original IP header. The values
unset and set cause the bit to be always unset or
always set, respectively. By default, the bit is
not set.

flowlabel FLOWLABEL - specifies the flow label to
use in outgoing packets.

dstport PORT - specifies the UDP destination port
to communicate to the remote
VXLAN tunnel endpoint.

srcport MIN MAX - specifies the range of port
numbers to use as UDP source ports to communicate
to the remote VXLAN tunnel endpoint.

[no]learning - specifies if unknown source link
layer addresses and IP addresses are entered into
the VXLAN device forwarding database.

[no]rsc - specifies if route short circuit is
turned on.

[no]proxy - specifies ARP proxy is turned on.

[no]l2miss - specifies if netlink LLADDR miss
notifications are generated.

[no]l3miss - specifies if netlink IP ADDR miss
notifications are generated.

[no]udpcsum - specifies if UDP checksum is
calculated for transmitted packets over IPv4.

[no]udp6zerocsumtx - skip UDP checksum calculation
for transmitted packets over IPv6.

[no]udp6zerocsumrx - allow incoming UDP packets
over IPv6 with zero checksum field.

[no]localbypass - if FDB destination is local, with
nolocalbypass set, forward encapsulated packets to
the userspace network stack. If there is a
userspace process listening for these packets, it
will have a chance to process them. If localbypass
is active (default), bypass the kernel network
stack and inject the packets into the target VXLAN
device, assuming one exists.

ageing SECONDS - specifies the lifetime in seconds
of FDB entries learnt by the kernel.

maxaddress NUMBER - specifies the maximum number of
FDB entries.

[no]external - specifies whether an external
control plane (e.g. ip route encap) or the internal
FDB should be used.

[no]vnifilter - specifies whether the vxlan device
is capable of vni filtering. Only works with a
vxlan device with external flag set. once enabled,
bridge vni command is used to manage the vni
filtering table on the device. The device can only
receive packets with vni's configured in the vni
filtering table.

gbp - enables the Group Policy extension (VXLAN-
GBP).

Allows one to transport group policy context
across VXLAN network peers. If enabled,
includes the mark of a packet in the VXLAN
header for outgoing packets and fills the
packet mark based on the information found in
the VXLAN header for incoming packets.

Format of upper 16 bits of packet mark (flags);

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|-|-|-|-|-|-|-|-|-|D|-|-|A|-|-|-|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

D := Don't Learn bit. When set, this bit
indicates that the egress VTEP MUST NOT learn
the source address of the encapsulated frame.

A := Indicates that the group policy has
already been applied to this packet. Policies
MUST NOT be applied by devices when the A bit
is set.

Format of lower 16 bits of packet mark (policy
ID):

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Group Policy ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Example:
iptables -A OUTPUT [...] -j MARK --set-mark
0x800FF

gpe - enables the Generic Protocol extension
(VXLAN-GPE). Currently, this is only supported
together with the external keyword.

VETH, VXCAN Type Support
For a link of types VETH/VXCAN the following additional
arguments are supported:

ip link add DEVICE type { veth | vxcan } [ peer name NAME ]

peer name NAME - specifies the virtual pair device
name of the VETH/VXCAN tunnel.

IPIP, SIT Type Support
For a link of type IPIPorSIT the following additional
arguments are supported:

ip link add DEVICE type { ipip | sit } remote ADDR local
ADDR [ encap { fou | gue | none } ] [ encap-sport { PORT |
auto } ] [ encap-dport PORT ] [ [no]encap-csum ] [
[no]encap-remcsum ] [ mode { ip6ip | ipip | mplsip | any
} ] [ external ]

remote ADDR - specifies the remote address of the
tunnel.

local ADDR - specifies the fixed local address for
tunneled packets. It must be an address on another
interface on this host.

encap { fou | gue | none } - specifies type of
secondary UDP encapsulation. "fou" indicates Foo-
Over-UDP, "gue" indicates Generic UDP
Encapsulation.

encap-sport { PORT | auto } - specifies the source
port in UDP encapsulation. PORT indicates the port
by number, "auto" indicates that the port number
should be chosen automatically (the kernel picks a
flow based on the flow hash of the encapsulated
packet).

[no]encap-csum - specifies if UDP checksums are
enabled in the secondary encapsulation.

[no]encap-remcsum - specifies if Remote Checksum
Offload is enabled. This is only applicable for
Generic UDP Encapsulation.

mode { ip6ip | ipip | mplsip | any } - specifies
mode in which device should run. "ip6ip" indicates
IPv6-Over-IPv4, "ipip" indicates "IPv4-Over-IPv4",
"mplsip" indicates MPLS-Over-IPv4, "any" indicates
IPv6, IPv4 or MPLS Over IPv4. Supported for SIT
where the default is "ip6ip" and IPIP where the
default is "ipip". IPv6-Over-IPv4 is not supported
for IPIP.

external - make this tunnel externally controlled
(e.g. ip route encap).

GRE Type Support
For a link of type GRE or GRETAP the following additional
arguments are supported:

ip link add DEVICE type { gre | gretap } remote ADDR local
ADDR [ [no][i|o]seq ] [ [i|o]key KEY | no[i|o]key ] [
[no][i|o]csum ] [ ttl TTL ] [ tos TOS ] [ [no]pmtudisc ] [
[no]ignore-df ] [ dev PHYS_DEV ] [ encap { fou | gue | none
} ] [ encap-sport { PORT | auto } ] [ encap-dport PORT ] [
[no]encap-csum ] [ [no]encap-remcsum ] [ external ]

remote ADDR - specifies the remote address of the
tunnel.

local ADDR - specifies the fixed local address for
tunneled packets. It must be an address on another
interface on this host.

[no][i|o]seq - serialize packets. The oseq flag
enables sequencing of outgoing packets. The iseq
flag requires that all input packets are
serialized.

[i|o]key KEY | no[i|o]key - use keyed GRE with key
KEY. KEY is either a number or an IPv4 address-like
dotted quad. The key parameter specifies the same
key to use in both directions. The ikey and okey
parameters specify different keys for input and
output.

[no][i|o]csum - generate/require checksums for
tunneled packets. The ocsum flag calculates
checksums for outgoing packets. The icsum flag
requires that all input packets have the correct
checksum. The csum flag is equivalent to the
combination icsum ocsum .

ttl TTL - specifies the TTL value to use in
outgoing packets.

tos TOS - specifies the TOS value to use in
outgoing packets.

[no]pmtudisc - enables/disables Path MTU Discovery
on this tunnel. It is enabled by default. Note
that a fixed ttl is incompatible with this option:
tunneling with a fixed ttl always makes pmtu
discovery.

[no]ignore-df - enables/disables IPv4 DF
suppression on this tunnel. Normally datagrams
that exceed the MTU will be fragmented; the
presence of the DF flag inhibits this, resulting
instead in an ICMP Unreachable (Fragmentation
Required) message. Enabling this attribute causes
the DF flag to be ignored.

dev PHYS_DEV - specifies the physical device to use
for tunnel endpoint communication.

encap { fou | gue | none } - specifies type of
secondary UDP encapsulation. "fou" indicates Foo-
Over-UDP, "gue" indicates Generic UDP
Encapsulation.

[no]encap-csum - specifies if UDP checksums are
enabled in the secondary encapsulation.

[no]encap-remcsum - specifies if Remote Checksum
Offload is enabled. This is only applicable for
Generic UDP Encapsulation.

external - make this tunnel externally controlled
(e.g. ip route encap).

IP6GRE/IP6GRETAP Type Support
For a link of type IP6GRE/IP6GRETAP the following
additional arguments are supported:

ip link add DEVICE type { ip6gre | ip6gretap } remote ADDR
local ADDR [ [no][i|o]seq ] [ [i|o]key KEY | no[i|o]key ] [
[no][i|o]csum ] [ hoplimit TTL ] [ encaplimit ELIM ] [
tclass TCLASS ] [ flowlabel FLOWLABEL ] [ dscp inherit ] [
[no]allow-localremote ] [ dev PHYS_DEV ] [ external ]

remote ADDR - specifies the remote IPv6 address of
the tunnel.

local ADDR - specifies the fixed local IPv6 address
for tunneled packets. It must be an address on
another interface on this host.

[no][i|o]seq - serialize packets. The oseq flag
enables sequencing of outgoing packets. The iseq
flag requires that all input packets are
serialized.

hoplimit TTL - specifies Hop Limit value to use in
outgoing packets.

encaplimit ELIM - specifies a fixed encapsulation
limit. Default is 4.

flowlabel FLOWLABEL - specifies a fixed flowlabel.

[no]allow-localremote - specifies whether to allow
remote endpoint to have an address configured on
local host.

tclass TCLASS - specifies the traffic class field
on tunneled packets, which can be specified as
either a two-digit hex value (e.g. c0) or a
predefined string (e.g. internet). The value
inherit causes the field to be copied from the
original IP header. The values inherit/STRING or
inherit/00..ff will set the field to STRING or
00..ff when tunneling non-IP packets. The default
value is 00.

external - make this tunnel externally controlled
(or not, which is the default). In the kernel,
this is referred to as collect metadata mode. This
flag is mutually exclusive with the remote, local,
seq, key, csum, hoplimit, encaplimit, flowlabel and
tclass options.

IPoIB Type Support
For a link of type IPoIB the following additional arguments
are supported:

ip link add DEVICE name NAME type ipoib [ pkey PKEY ] [
mode MODE ]

pkey PKEY - specifies the IB P-Key to use.

mode MODE - specifies the mode (datagram or
connected) to use.

ERSPAN Type Support
For a link of type ERSPAN/IP6ERSPAN the following
additional arguments are supported:

ip link add DEVICE type { erspan | ip6erspan } remote ADDR
local ADDR seq key KEY erspan_ver version [ erspan IDX ] [
erspan_dir { ingress | egress } ] [ erspan_hwid hwid ] [
[no]allow-localremote ] [ external ]

remote ADDR - specifies the remote address of the
tunnel.

local ADDR - specifies the fixed local address for
tunneled packets. It must be an address on another
interface on this host.

erspan_ver version - specifies the ERSPAN version
number. version indicates the ERSPAN version to be
created: 0 for version 0 type I, 1 for version 1
(type II) or 2 for version 2 (type III).

erspan IDX - specifies the ERSPAN v1 index field.
IDX indicates a 20 bit index/port number associated
with the ERSPAN traffic's source port and
direction.

erspan_dir { ingress | egress } - specifies the
ERSPAN v2 mirrored traffic's direction.

erspan_hwid hwid - an unique identifier of an
ERSPAN v2 engine within a system. hwid is a 6-bit
value for users to configure.

[no]allow-localremote - specifies whether to allow
remote endpoint to have an address configured on
local host.

external - make this tunnel externally controlled
(or not, which is the default). In the kernel,
this is referred to as collect metadata mode. This
flag is mutually exclusive with the remote, local,
erspan_ver, erspan, erspan_dir and erspan_hwid
options.

GENEVE Type Support
For a link of type GENEVE the following additional
arguments are supported:

ip link add DEVICE type geneve id VNI remote IPADDR [ ttl
TTL ] [ tos TOS ] [ df DF ] [ flowlabel FLOWLABEL ] [
dstport PORT ] [ [no]external ] [ [no]udpcsum ] [
[no]udp6zerocsumtx ] [ [no]udp6zerocsumrx ] [
innerprotoinherit ]

id VNI - specifies the Virtual Network Identifier
to use.

remote IPADDR - specifies the unicast destination
IP address to use in outgoing packets.

ttl TTL - specifies the TTL value to use in
outgoing packets. "0" or "auto" means use whatever
default value, "inherit" means inherit the inner
protocol's ttl. Default option is "0".

tos TOS - specifies the TOS value to use in
outgoing packets.

flowlabel FLOWLABEL - specifies the flow label to
use in outgoing packets.

dstport PORT - select a destination port other than
the default of 6081.

[no]external - make this tunnel externally
controlled (or not, which is the default). This
flag is mutually exclusive with the id, remote,
ttl, tos and flowlabel options.

[no]udpcsum - specifies if UDP checksum is
calculated for transmitted packets over IPv4.

[no]udp6zerocsumtx - skip UDP checksum calculation
for transmitted packets over IPv6.

[no]udp6zerocsumrx - allow incoming UDP packets
over IPv6 with zero checksum field.

innerprotoinherit - use IPv4/IPv6 as inner protocol
instead of Ethernet.

Bareudp Type Support
For a link of type Bareudp the following additional
arguments are supported:

ip link add DEVICE type bareudp dstport PORT ethertype
PROTO [ srcportmin PORT ] [ [no]multiproto ]

dstport PORT - specifies the destination port for
the UDP tunnel.

ethertype PROTO - specifies the ethertype of the L3
protocol being tunnelled. ethertype can be given
as plain Ethernet protocol number or using the
protocol name ("ipv4", "ipv6", "mpls_uc", etc.).

srcportmin PORT - selects the lowest value of the
UDP tunnel source port range.

[no]multiproto - activates support for protocols
similar to the one specified by ethertype. When
ethertype is "mpls_uc" (that is, unicast MPLS),
this allows the tunnel to also handle multicast
MPLS. When ethertype is "ipv4", this allows the
tunnel to also handle IPv6. This option is disabled
by default.

AMT Type Support
For a link of type AMT the following additional arguments
are supported:

ip link add DEVICE type AMT discovery IPADDR mode { gateway
| relay } local IPADDR dev PHYS_DEV [ relay_port PORT ] [
gateway_port PORT ] [ max_tunnels NUMBER ]

discovery IPADDR - specifies the unicast discovery
IP address to use to find remote IP address.

mode { gateway | relay } - specifies the role of
AMT, Gateway or Relay

local IPADDR - specifies the source IP address to
use in outgoing packets.

dev PHYS_DEV - specifies the underlying physical
interface from which transform traffic is sent and
received.

relay_port PORT - specifies the UDP Relay port to
communicate to the Relay.

gateway_port PORT - specifies the UDP Gateway port
to communicate to the Gateway.

max_tunnels NUMBER - specifies the maximum number
of tunnels.

MACVLAN and MACVTAP Type Support
For a link of type MACVLAN or MACVTAP the following
additional arguments are supported:

ip link add link DEVICE name NAME type { macvlan | macvtap
} mode { private | vepa | bridge | passthru [ nopromisc ]
| source [ nodst ] } [ bcqueuelen { LENGTH } ] [ bclim
LIMIT ]

type { macvlan | macvtap } - specifies the link
type to use. macvlan creates just a virtual
interface, while macvtap in addition creates a
character device /dev/tapX to be used just like a
tuntap device.

mode private - Do not allow communication between
macvlan instances on the same physical interface,
even if the external switch supports hairpin mode.

mode vepa - Virtual Ethernet Port Aggregator mode.
Data from one macvlan instance to the other on the
same physical interface is transmitted over the
physical interface. Either the attached switch
needs to support hairpin mode, or there must be a
TCP/IP router forwarding the packets in order to
allow communication. This is the default mode.

mode bridge - In bridge mode, all endpoints are
directly connected to each other, communication is
not redirected through the physical interface's
peer.

mode passthru [ nopromisc ] - This mode gives more
power to a single endpoint, usually in macvtap
mode. It is not allowed for more than one endpoint
on the same physical interface. All traffic will be
forwarded to this endpoint, allowing virtio guests
to change MAC address or set promiscuous mode in
order to bridge the interface or create vlan
interfaces on top of it. By default, this mode
forces the underlying interface into promiscuous
mode. Passing the nopromisc flag prevents this, so
the promisc flag may be controlled using standard
tools.

mode source [ nodst ] - allows one to set a list of
allowed mac address, which is used to match against
source mac address from received frames on
underlying interface. This allows creating mac
based VLAN associations, instead of standard port
or tag based. The feature is useful to deploy
802.1x mac based behavior, where drivers of
underlying interfaces doesn't allows that. By
default, packets are also considered (duplicated)
for destination-based MACVLAN. Passing the nodst
flag stops matching packets from also going through
the destination-based flow.

bcqueuelen { LENGTH } - Set the length of the RX
queue used to process broadcast and multicast
packets. LENGTH must be a positive integer in the
range [0-4294967295]. Setting a length of 0 will
effectively drop all broadcast/multicast traffic.
If not specified the macvlan driver default (1000)
is used. Note that all macvlans that share the
same underlying device are using the same queue.
The parameter here is a request, the actual queue
length used will be the maximum length that any
macvlan interface has requested. When listing
device parameters both the bcqueuelen parameter as
well as the actual used bcqueuelen are listed to
better help the user understand the setting.

bclim LIMIT - Set the threshold for broadcast
queueing. LIMIT must be a 32-bit integer. Setting
this to -1 disables broadcast queueing altogether.
Otherwise a multicast address will be queued as
broadcast if the number of devices using it is
greater than the given value.

High-availability Seamless Redundancy (HSR) Support
For a link of type HSR the following additional arguments
are supported:

ip link add link DEVICE name NAME type hsr slave1 SLAVE1-IF
slave2 SLAVE2-IF [ supervision ADDR-BYTE ] [ version { 0 |
1 } [ proto { 0 | 1 } ]

type hsr - specifies the link type to use, here
HSR.

slave1 SLAVE1-IF - Specifies the physical device
used for the first of the two ring ports.

slave2 SLAVE2-IF - Specifies the physical device
used for the second of the two ring ports.

supervision ADDR-BYTE - The last byte of the
multicast address used for HSR supervision frames.
Default option is "0", possible values 0-255.

version { 0 | 1 } - Selects the protocol version of
the interface. Default option is "0", which
corresponds to the 2010 version of the HSR
standard. Option "1" activates the 2012 version.

proto { 0 | 1 } - Selects the protocol at the
interface. Default option is "0", which corresponds
to the HSR standard. Option "1" activates the
Parallel Redundancy Protocol (PRP).

BRIDGE Type Support
For a link of type BRIDGE the following additional
arguments are supported:

ip link add DEVICE type bridge [ ageing_time AGEING_TIME ]
[ group_fwd_mask MASK ] [ group_address ADDRESS ] [
forward_delay FORWARD_DELAY ] [ hello_time HELLO_TIME ] [
max_age MAX_AGE ] [ stp_state STP_STATE ] [ priority
PRIORITY ] [ no_linklocal_learn NO_LINKLOCAL_LEARN ] [
vlan_filtering VLAN_FILTERING ] [ vlan_protocol
VLAN_PROTOCOL ] [ vlan_default_pvid VLAN_DEFAULT_PVID ] [
vlan_stats_enabled VLAN_STATS_ENABLED ] [
vlan_stats_per_port VLAN_STATS_PER_PORT ] [ mcast_snooping
MULTICAST_SNOOPING ] [ mcast_vlan_snooping
MULTICAST_VLAN_SNOOPING ] [ mcast_router MULTICAST_ROUTER ]
[ mcast_query_use_ifaddr MCAST_QUERY_USE_IFADDR ] [
mcast_querier MULTICAST_QUERIER ] [ mcast_hash_elasticity
HASH_ELASTICITY ] [ mcast_hash_max HASH_MAX ] [
mcast_last_member_count LAST_MEMBER_COUNT ] [
mcast_startup_query_count STARTUP_QUERY_COUNT ] [
mcast_last_member_interval LAST_MEMBER_INTERVAL ] [
mcast_membership_interval MEMBERSHIP_INTERVAL ] [
mcast_querier_interval QUERIER_INTERVAL ] [
mcast_query_interval QUERY_INTERVAL ] [
mcast_query_response_interval QUERY_RESPONSE_INTERVAL ] [
mcast_startup_query_interval STARTUP_QUERY_INTERVAL ] [
mcast_stats_enabled MCAST_STATS_ENABLED ] [
mcast_igmp_version IGMP_VERSION ] [ mcast_mld_version
MLD_VERSION ] [ nf_call_iptables NF_CALL_IPTABLES ] [
nf_call_ip6tables NF_CALL_IP6TABLES ] [ nf_call_arptables
NF_CALL_ARPTABLES ]

ageing_time AGEING_TIME - configure the bridge's
FDB entries ageing time, ie the number of seconds a
MAC address will be kept in the FDB after a packet
has been received from that address. after this
time has passed, entries are cleaned up.

group_fwd_mask MASK - set the group forward mask.
This is the bitmask that is applied to decide
whether to forward incoming frames destined to
link-local addresses, ie addresses of the form
01:80:C2:00:00:0X (defaults to 0, ie the bridge
does not forward any link-local frames).

group_address ADDRESS - set the MAC address of the
multicast group this bridge uses for STP. The
address must be a link-local address in standard
Ethernet MAC address format, ie an address of the
form 01:80:C2:00:00:0X, with X
in [0, 4..f].

forward_delay FORWARD_DELAY - set the forwarding
delay in seconds, ie the time spent in LISTENING
state (before moving to LEARNING) and in LEARNING
state (before moving to FORWARDING). Only relevant
if STP is enabled. Valid values are between 2 and
30.

hello_time HELLO_TIME - set the time in seconds
between hello packets sent by the bridge, when it
is a root bridge or a designated bridges. Only
relevant if STP is enabled. Valid values are
between 1 and 10.

max_age MAX_AGE - set the hello packet timeout, ie
the time in seconds until another bridge in the
spanning tree is assumed to be dead, after
reception of its last hello message. Only relevant
if STP is enabled. Valid values are between 6 and
40.

stp_state STP_STATE - turn spanning tree protocol
on (STP_STATE > 0) or off (STP_STATE == 0). for
this bridge.

priority PRIORITY - set this bridge's spanning tree
priority, used during STP root bridge election.
PRIORITY is a 16bit unsigned integer.

no_linklocal_learn NO_LINKLOCAL_LEARN - turn link-
local learning on (NO_LINKLOCAL_LEARN == 0) or off
(NO_LINKLOCAL_LEARN > 0). When disabled, the
bridge will not learn from link-local frames
(default: enabled).

vlan_filtering VLAN_FILTERING - turn VLAN filtering
on (VLAN_FILTERING > 0) or off (VLAN_FILTERING ==
0). When disabled, the bridge will not consider
the VLAN tag when handling packets.

vlan_protocol { 802.1Q | 802.1ad } - set the
protocol used for VLAN filtering.

vlan_default_pvid VLAN_DEFAULT_PVID - set the
default PVID (native/untagged VLAN ID) for this
bridge.

vlan_stats_enabled VLAN_STATS_ENABLED - enable
(VLAN_STATS_ENABLED == 1) or disable
(VLAN_STATS_ENABLED == 0) per-VLAN stats
accounting.

vlan_stats_per_port VLAN_STATS_PER_PORT - enable
(VLAN_STATS_PER_PORT == 1) or disable
(VLAN_STATS_PER_PORT == 0) per-VLAN per-port stats
accounting. Can be changed only when there are no
port VLANs configured.

mcast_snooping MULTICAST_SNOOPING - turn multicast
snooping on (MULTICAST_SNOOPING > 0) or off
(MULTICAST_SNOOPING == 0).

mcast_vlan_snooping MULTICAST_VLAN_SNOOPING - turn
multicast VLAN snooping on (MULTICAST_VLAN_SNOOPING
> 0) or off (MULTICAST_VLAN_SNOOPING == 0).

mcast_router MULTICAST_ROUTER - set bridge's
multicast router if IGMP snooping is enabled.
MULTICAST_ROUTER is an integer value having the
following meaning:

0 - disabled.

1 - automatic (queried).

2 - permanently enabled.

mcast_query_use_ifaddr MCAST_QUERY_USE_IFADDR -
whether to use the bridge's own IP address as
source address for IGMP queries
(MCAST_QUERY_USE_IFADDR > 0) or the default of
0.0.0.0 (MCAST_QUERY_USE_IFADDR == 0).

mcast_querier MULTICAST_QUERIER - enable
(MULTICAST_QUERIER > 0) or disable
(MULTICAST_QUERIER == 0) IGMP querier, ie sending
of multicast queries by the bridge (default:
disabled).

mcast_querier_interval QUERIER_INTERVAL - interval
between queries sent by other routers. if no
queries are seen after this delay has passed, the
bridge will start to send its own queries (as if
mcast_querier was enabled).

mcast_hash_elasticity HASH_ELASTICITY - set
multicast database hash elasticity, ie the maximum
chain length in the multicast hash table (defaults
to 4).

mcast_hash_max HASH_MAX - set maximum size of
multicast hash table (defaults to 512, value must
be a power of 2).

mcast_last_member_count LAST_MEMBER_COUNT - set
multicast last member count, ie the number of
queries the bridge will send before stopping
forwarding a multicast group after a "leave"
message has been received (defaults to 2).

mcast_last_member_interval LAST_MEMBER_INTERVAL -
interval between queries to find remaining members
of a group, after a "leave" message is received.

mcast_startup_query_count STARTUP_QUERY_COUNT - set
the number of IGMP queries to send during startup
phase (defaults to 2).

mcast_startup_query_interval STARTUP_QUERY_INTERVAL
- interval between queries in the startup phase.

mcast_query_interval QUERY_INTERVAL - interval
between queries sent by the bridge after the end of
the startup phase.

mcast_query_response_interval
QUERY_RESPONSE_INTERVAL - set the Max Response
Time/Maximum Response Delay for IGMP/MLD queries
sent by the bridge.

mcast_membership_interval MEMBERSHIP_INTERVAL -
delay after which the bridge will leave a group, if
no membership reports for this group are received.

mcast_stats_enabled MCAST_STATS_ENABLED - enable
(MCAST_STATS_ENABLED > 0) or disable
(MCAST_STATS_ENABLED == 0) multicast (IGMP/MLD)
stats accounting.

mcast_igmp_version IGMP_VERSION - set the IGMP
version.

mcast_mld_version MLD_VERSION - set the MLD
version.

nf_call_iptables NF_CALL_IPTABLES - enable
(NF_CALL_IPTABLES > 0) or disable (NF_CALL_IPTABLES
== 0) iptables hooks on the bridge.

nf_call_ip6tables NF_CALL_IP6TABLES - enable
(NF_CALL_IP6TABLES > 0) or disable
(NF_CALL_IP6TABLES == 0) ip6tables hooks on the
bridge.

nf_call_arptables NF_CALL_ARPTABLES - enable
(NF_CALL_ARPTABLES > 0) or disable
(NF_CALL_ARPTABLES == 0) arptables hooks on the
bridge.

MACsec Type Support
For a link of type MACsec the following additional
arguments are supported:

ip link add link DEVICE name NAME type macsec [ [ address
<lladdr> ] port PORT | sci SCI ] [ cipher CIPHER_SUITE ] [
icvlen { 8..16 } ] [ encrypt { on | off } ] [ send_sci { on
| off } ] [ end_station { on | off } ] [ scb { on | off } ]
[ protect { on | off } ] [ replay { on | off } window {
0..2^32-1 } ] [ validate { strict | check | disabled } ] [
encodingsa { 0..3 } ]

address <lladdr> - sets the system identifier
component of secure channel for this MACsec device.

port PORT - sets the port number component of
secure channel for this MACsec device, in a range
from 1 to 65535 inclusive. Numbers with a leading "
0 " or " 0x " are interpreted as octal and
hexadecimal, respectively.

sci SCI - sets the secure channel identifier for
this MACsec device. SCI is a 64bit wide number in
hexadecimal format.

cipher CIPHER_SUITE - defines the cipher suite to
use.

icvlen LENGTH - sets the length of the Integrity
Check Value (ICV).

encrypt on or encrypt off - switches between
authenticated encryption, or authenticity mode
only.

send_sci on or send_sci off - specifies whether the
SCI is included in every packet, or only when it is
necessary.

end_station on or end_station off - sets the End
Station bit.

scb on or scb off - sets the Single Copy Broadcast
bit.

protect on or protect off - enables MACsec
protection on the device.

replay on or replay off - enables replay protection
on the device.

window SIZE - sets the size of the replay
window.

validate strict or validate check or validate
disabled - sets the validation mode on the device.

encodingsa AN - sets the active secure association
for transmission.

VRF Type Support
For a link of type VRF the following additional arguments
are supported:

ip link add DEVICE type vrf table TABLE

table table id associated with VRF device

RMNET Type Support
For a link of type RMNET the following additional arguments
are supported:

ip link add link DEVICE name NAME type rmnet mux_id MUXID

mux_id MUXID - specifies the mux identifier for the
rmnet device, possible values 1-254.

XFRM Type Support
For a link of type XFRM the following additional arguments
are supported:

ip link add DEVICE type xfrm dev PHYS_DEV [ if_id IF_ID ] [
external ]

dev PHYS_DEV - specifies the underlying physical
interface from which transform traffic is sent and
received.

if_id IF-ID - specifies the hexadecimal lookup key
used to send traffic to and from specific xfrm
policies. Policies must be configured with the same
key. If not set, the key defaults to 0 and will
match any policies which similarly do not have a
lookup key configuration.

external - make this device externally controlled.
This flag is mutually exclusive with the dev and
if_id options.

GTP Type Support
For a link of type GTP the following additional arguments
are supported:

ip link add DEVICE type gtp role ROLE hsize HSIZE

role ROLE - specifies the role of the GTP device,
either sgsn or ggsn

hsize HSIZE - specifies size of the hashtable which
stores PDP contexts

restart_count RESTART_COUNT - GTP instance restart
counter

ip link delete - delete virtual link
dev DEVICE
specifies the virtual device to act operate on.

group GROUP
specifies the group of virtual links to delete. Group 0 is
not allowed to be deleted since it is the default group.

type TYPE
specifies the type of the device.

ip link set - change device attributes
Warning: If multiple parameter changes are requested, ip aborts
immediately after any of the changes have failed. This is the
only case when ip can move the system to an unpredictable state.
The solution is to avoid changing several parameters with one ip
link set call. The modifier change is equivalent to set.

dev DEVICE
DEVICE specifies network device to operate on. When
configuring SR-IOV Virtual Function (VF) devices, this
keyword should specify the associated Physical Function
(PF) device.

group GROUP
GROUP has a dual role: If both group and dev are present,
then move the device to the specified group. If only a
group is specified, then the command operates on all
devices in that group.

up and down
change the state of the device to UP or DOWN.

arp on or arp off
change the NOARP flag on the device.

multicast on or multicast off
change the MULTICAST flag on the device.

allmulticast on or allmulticast off
change the ALLMULTI flag on the device. When enabled,
instructs network driver to retrieve all multicast packets
from the network to the kernel for further processing.

promisc on or promisc off
change the PROMISC flag on the device. When enabled,
activates promiscuous operation of the network device.

trailers on or trailers off
change the NOTRAILERS flag on the device, NOT used by the
Linux and exists for BSD compatibility.

protodown on or protodown off
change the PROTODOWN state on the device. Indicates that a
protocol error has been detected on the port. Switch
drivers can react to this error by doing a phys down on the
switch port.

protodown_reason PREASON on or off
set PROTODOWN reasons on the device. protodown reason bit
names can be enumerated under
/etc/iproute2/protodown_reasons.d/. possible reasons bits
0-31

dynamic on or dynamic off
change the DYNAMIC flag on the device. Indicates that
address can change when interface goes down (currently NOT
used by the Linux).

name NAME
change the name of the device. This operation is not
recommended if the device is running or has some addresses
already configured.

txqueuelen NUMBER

txqlen NUMBER
change the transmit queue length of the device.

mtu NUMBER
change the MTU of the device.

address LLADDRESS
change the station address of the interface.

broadcast LLADDRESS

brd LLADDRESS

peer LLADDRESS
change the link layer broadcast address or the peer address
when the interface is POINTOPOINT.

netns { PID | NETNSNAME | NETNSFILE }
move the device to the network namespace associated with
process PID or the name NETNSNAME or the file NETNSFILE.

Some devices are not allowed to change network namespace:
loopback, bridge, wireless. These are network namespace
local devices. In such case ip tool will return "Invalid
argument" error. It is possible to find out if device is
local to a single network namespace by checking netns-local
flag in the output of the ethtool:

ethtool -k DEVICE

To change network namespace for wireless devices the iw
tool can be used. But it allows one to change network
namespace only for physical devices and by process PID.

alias NAME
give the device a symbolic name for easy reference.

group GROUP
specify the group the device belongs to. The available
groups are listed in /usr/lib/iproute2/groupor
/etc/iproute2/group(hasprecedenceifexists).

vf NUM specify a Virtual Function device to be configured. The
associated PF device must be specified using the dev
parameter.

mac LLADDRESS - change the station address for the
specified VF. The vf parameter must be specified.

vlan VLANID - change the assigned VLAN for the
specified VF. When specified, all traffic sent from
the VF will be tagged with the specified VLAN ID.
Incoming traffic will be filtered for the specified
VLAN ID, and will have all VLAN tags stripped
before being passed to the VF. Setting this
parameter to 0 disables VLAN tagging and filtering.
The vf parameter must be specified.

qos VLAN-QOS - assign VLAN QOS (priority) bits for
the VLAN tag. When specified, all VLAN tags
transmitted by the VF will include the specified
priority bits in the VLAN tag. If not specified,
the value is assumed to be 0. Both the vf and vlan
parameters must be specified. Setting both vlan and
qos as 0 disables VLAN tagging and filtering for
the VF.

proto VLAN-PROTO - assign VLAN PROTOCOL for the
VLAN tag, either 802.1Q or 802.1ad. Setting to
802.1ad, all traffic sent from the VF will be
tagged with VLAN S-Tag. Incoming traffic will have
VLAN S-Tags stripped before being passed to the VF.
Setting to 802.1ad also enables an option to
concatenate another VLAN tag, so both S-TAG and C-
TAG will be inserted/stripped for outgoing/incoming
traffic, respectively. If not specified, the value
is assumed to be 802.1Q. Both the vf and vlan
parameters must be specified.

rate TXRATE -- change the allowed transmit
bandwidth, in Mbps, for the specified VF. Setting
this parameter to 0 disables rate limiting. vf
parameter must be specified. Please use new API
max_tx_rate option instead.

max_tx_rate TXRATE - change the allowed maximum
transmit bandwidth, in Mbps, for the specified VF.
Setting this parameter to 0 disables rate limiting.
vf parameter must be specified.

min_tx_rate TXRATE - change the allowed minimum
transmit bandwidth, in Mbps, for the specified VF.
Minimum TXRATE should be always <= Maximum TXRATE.
Setting this parameter to 0 disables rate limiting.
vf parameter must be specified.

spoofchk on|off - turn packet spoof checking on or
off for the specified VF.

query_rss on|off - toggle the ability of querying
the RSS configuration of a specific VF. VF RSS
information like RSS hash key may be considered
sensitive on some devices where this information is
shared between VF and PF and thus its querying may
be prohibited by default.

state auto|enable|disable - set the virtual link
state as seen by the specified VF. Setting to auto
means a reflection of the PF link state, enable
lets the VF to communicate with other VFs on this
host even if the PF link state is down, disable
causes the HW to drop any packets sent by the VF.

trust on|off - trust the specified VF user. This
enables that VF user can set a specific feature
which may impact security and/or performance. (e.g.
VF multicast promiscuous mode)

node_guid eui64 - configure node GUID for
Infiniband VFs.

port_guid eui64 - configure port GUID for
Infiniband VFs.

xdp object | pinned | off
set (or unset) a XDP ("eXpress Data Path") BPF program to
run on every packet at driver level. ip link output will
indicate a xdp flag for the networking device. If the
driver does not have native XDP support, the kernel will
fall back to a slower, driver-independent "generic" XDP
variant. The ip link output will in that case indicate
xdpgeneric instead of xdp only. If the driver does have
native XDP support, but the program is loaded under
xdpgeneric object | pinned then the kernel will use the
generic XDP variant instead of the native one. xdpdrv has
the opposite effect of requestsing that the automatic
fallback to the generic XDP variant be disabled and in case
driver is not XDP-capable error should be returned. xdpdrv
also disables hardware offloads. xdpoffload in ip link
output indicates that the program has been offloaded to
hardware and can also be used to request the "offload"
mode, much like xdpgeneric it forces program to be
installed specifically in HW/FW of the apater.

off (or none ) - Detaches any currently attached XDP/BPF
program from the given device.

object FILE - Attaches a XDP/BPF program to the given
device. The FILE points to a BPF ELF file (f.e. generated
by LLVM) that contains the BPF program code, map
specifications, etc. If a XDP/BPF program is already
attached to the given device, an error will be thrown. If
no XDP/BPF program is currently attached, the device
supports XDP and the program from the BPF ELF file passes
the kernel verifier, then it will be attached to the
device. If the option -force is passed to ip then any prior
attached XDP/BPF program will be atomically overridden and
no error will be thrown in this case. If no section option
is passed, then the default section name ("prog") will be
assumed, otherwise the provided section name will be used.
If no verbose option is passed, then a verifier log will
only be dumped on load error. See also EXAMPLES section
for usage examples.

section NAME - Specifies a section name that contains the
BPF program code. If no section name is specified, the
default one ("prog") will be used. This option is to be
passed with the object option.

program NAME - Specifies the BPF program name that need to
be attached. When the program name is specified, the
section name parameter will be ignored. This option only
works when iproute2 build with libbpf support.

verbose - Act in verbose mode. For example, even in case of
success, this will print the verifier log in case a program
was loaded from a BPF ELF file.

pinned FILE - Attaches a XDP/BPF program to the given
device. The FILE points to an already pinned BPF program in
the BPF file system. The option section doesn't apply here,
but otherwise semantics are the same as with the option
object described already.

master DEVICE
set master device of the device (enslave device).

nomaster
unset master device of the device (release device).

addrgenmode eui64|none|stable_secret|random
set the IPv6 address generation mode

eui64 - use a Modified EUI-64 format interface identifier

none - disable automatic address generation

stable_secret - generate the interface identifier based on
a preset
/proc/sys/net/ipv6/conf/{default,DEVICE}/stable_secret

random - like stable_secret, but auto-generate a new random
secret if none is set

link-netnsid
set peer netnsid for a cross-netns interface

type ETYPE TYPE_ARGS
Change type-specific settings. For a list of supported
types and arguments refer to the description of ip link add
above. In addition to that, it is possible to manipulate
settings to slave devices:

Bridge Slave Support
For a link with master bridge the following additional
arguments are supported:

ip link set type bridge_slave [ fdb_flush ] [ state STATE ]
[ priority PRIO ] [ cost COST ] [ guard { on | off } ] [
hairpin { on | off } ] [ fastleave { on | off } ] [
root_block { on | off } ] [ learning { on | off } ] [ flood
{ on | off } ] [ proxy_arp { on | off } ] [ proxy_arp_wifi
{ on | off } ] [ mcast_router MULTICAST_ROUTER ] [
mcast_fast_leave { on | off} ] [ bcast_flood { on | off } ]
[ mcast_flood { on | off } ] [ mcast_to_unicast { on | off
} ] [ group_fwd_mask MASK ] [ neigh_suppress { on | off } ]
[ neigh_vlan_suppress { on | off } ] [ vlan_tunnel { on |
off } ] [ isolated { on | off } ] [ locked { on | off } ] [
mab { on | off } ] [ backup_port DEVICE ] [ nobackup_port ]
[ backup_nhid NHID ]

fdb_flush - flush bridge slave's fdb dynamic
entries.

state STATE - Set port state. STATE is a number
representing the following states: 0 (disabled), 1
(listening), 2 (learning), 3 (forwarding), 4
(blocking).

priority PRIO - set port priority (allowed values
are between 0 and 63, inclusively).

cost COST - set port cost (allowed values are
between 1 and 65535, inclusively).

guard { on | off } - block incoming BPDU packets on
this port.

hairpin { on | off } - enable hairpin mode on this
port. This will allow incoming packets on this port
to be reflected back.

fastleave { on | off } - enable multicast fast
leave on this port.

root_block { on | off } - block this port from
becoming the bridge's root port.

learning { on | off } - allow MAC address learning
on this port.

flood { on | off } - open the flood gates on this
port, i.e. forward all unicast frames to this port
also. Requires proxy_arp and proxy_arp_wifi to be
turned off.

proxy_arp { on | off } - enable proxy ARP on this
port.

proxy_arp_wifi { on | off } - enable proxy ARP on
this port which meets extended requirements by IEEE
802.11 and Hotspot 2.0 specifications.

mcast_router MULTICAST_ROUTER - configure this port
for having multicast routers attached. A port with
a multicast router will receive all multicast
traffic. MULTICAST_ROUTER may be either 0 to
disable multicast routers on this port, 1 to let
the system detect the presence of routers (this is
the default), 2 to permanently enable multicast
traffic forwarding on this port or 3 to enable
multicast routers temporarily on this port, not
depending on incoming queries.

mcast_fast_leave { on | off } - this is a synonym
to the fastleave option above.

bcast_flood { on | off } - controls flooding of
broadcast traffic on the given port. By default
this flag is on.

mcast_flood { on | off } - controls whether a given
port will flood multicast traffic for which there
is no MDB entry. By default this flag is on.

mcast_to_unicast { on | off } - controls whether a
given port will replicate packets using unicast
instead of multicast. By default this flag is off.

neigh_suppress { on | off } - controls whether
neigh discovery (arp and nd) proxy and suppression
is enabled on the port. By default this flag is
off.

neigh_vlan_suppress { on | off } - controls whether
per-VLAN neigh discovery (arp and nd) proxy and
suppression is enabled on the port. When on, the
bridge link option neigh_suppress has no effect and
the per-VLAN state is set using the bridge vlan
option neigh_suppress. By default this flag is off.

vlan_tunnel { on | off } - controls whether vlan to
tunnel mapping is enabled on the port. By default
this flag is off.

locked { on | off } - controls whether a port is
locked or not. When locked, non-link-local frames
received through the port are dropped unless an FDB
entry with the MAC source address points to the
port. The common use case is IEEE 802.1X where
hosts can authenticate themselves by exchanging
EAPOL frames with an authenticator. After
authentication is complete, the user space control
plane can install a matching FDB entry to allow
traffic from the host to be forwarded by the
bridge. When learning is enabled on a locked port,
the no_linklocal_learn bridge option needs to be on
to prevent the bridge from learning from received
EAPOL frames. By default this flag is off.

mab { on | off } - controls whether MAC
Authentication Bypass (MAB) is enabled on the port
or not. MAB can only be enabled on a locked port
that has learning enabled. When enabled, FDB
entries are learned from received traffic and have
the "locked" FDB flag set. The flag can only be set
by the kernel and it indicates that the FDB entry
cannot be used to authenticate the corresponding
host. User space can decide to authenticate the
host by replacing the FDB entry and clearing the
"locked" FDB flag. Locked FDB entries can roam to
unlocked (authorized) ports in which case the
"locked" flag is cleared. FDB entries cannot roam
to locked ports regardless of MAB being enabled or
not. Therefore, locked FDB entries are only created
if an FDB entry with the given {MAC, VID} does not
already exist. This behavior prevents
unauthenticated hosts from disrupting traffic
destined to already authenticated hosts. Locked FDB
entries act like regular dynamic entries with
respect to forwarding and aging. By default this
flag is off.

backup_port DEVICE - if the port loses carrier all
traffic will be redirected to the configured backup
port

nobackup_port - removes the currently configured
backup port

backup_nhid NHID - the FDB nexthop object ID (see
ip-nexthop(8)) to attach to packets being
redirected to a backup port that has VLAN tunnel
mapping enabled (via the vlan_tunnel option).
Setting a value of 0 (default) has the effect of
not attaching any ID.

Bonding Slave Support
For a link with master bond the following additional
arguments are supported:

ip link set type bond_slave [ queue_id ID ] [ prio PRIORITY
]

queue_id ID - set the slave's queue ID (a 16bit
unsigned value).

prio PRIORITY - set the slave's priority for active
slave re-selection during failover (a 32bit signed
value). This option only valid for active-
backup(1), balance-tlb (5) and balance-alb (6)
mode.

MACVLAN and MACVTAP Support
Modify list of allowed macaddr for link in source mode.

ip link set type { macvlan | macvap } [ macaddr COMMAND
MACADDR ... ]

Commands:
add - add MACADDR to allowed list

set - replace allowed list

del - remove MACADDR from allowed list

flush - flush whole allowed list

Update the broadcast/multicast queue length.

ip link set type { macvlan | macvap } [ bcqueuelen LENGTH
] [ bclim LIMIT ]

bcqueuelen LENGTH - Set the length of the RX queue
used to process broadcast and multicast packets.
LENGTH must be a positive integer in the range
[0-4294967295]. Setting a length of 0 will
effectively drop all broadcast/multicast traffic.
If not specified the macvlan driver default (1000)
is used. Note that all macvlans that share the
same underlying device are using the same queue.
The parameter here is a request, the actual queue
length used will be the maximum length that any
macvlan interface has requested. When listing
device parameters both the bcqueuelen parameter as
well as the actual used bcqueuelen are listed to
better help the user understand the setting.

DSA user port support
For a link having the DSA user port type, the following
additional arguments are supported:

ip link set type dsa [ conduit DEVICE ]

conduit DEVICE - change the DSA conduit (host
network interface) responsible for handling the
locally terminated traffic for the given DSA switch
user port. For a description of which network
interfaces are suitable for serving as conduit
interfaces of this user port, please see
https://www.kernel.org/doc/html/latest/networking/dsa/configuration.html#affinity-of-user-ports-to-cpu-ports
as well as what is supported by the driver in use.

master DEVICE - this is a synonym for "conduit".

ip link show - display device attributes
dev NAME (default)
NAME specifies the network device to show.

group GROUP
GROUP specifies what group of devices to show.

up only display running interfaces.

master DEVICE
DEVICE specifies the master device which enslaves devices
to show.

vrf NAME
NAME specifies the VRF which enslaves devices to show.

type TYPE
TYPE specifies the type of devices to show.

Note that the type name is not checked against the list of
supported types - instead it is sent as-is to the kernel.
Later it is used to filter the returned interface list by
comparing it with the relevant attribute in case the kernel
didn't filter already. Therefore any string is accepted,
but may lead to empty output.

nomaster
only show devices with no master

ip link xstats - display extended statistics
type TYPE
TYPE specifies the type of devices to display extended
statistics for.

ip link afstats - display address-family specific statistics
dev DEVICE
DEVICE specifies the device to display address-family
statistics for.

ip link help - display help
TYPE specifies which help of link type to display.

GROUP
may be a number or a string from /usr/lib/iproute2/group or
/etc/iproute2/group which can be manually filled and has
precedence if exists.

EXAMPLES top

       ip link show
           Shows the state of all network interfaces on the system.

       ip link show type bridge
           Shows the bridge devices.

       ip link show type vlan
           Shows the vlan devices.

       ip link show master br0
           Shows devices enslaved by br0

       ip link set dev ppp0 mtu 1400
           Change the MTU the ppp0 device.

       ip link add link eth0 name eth0.10 type vlan id 10
           Creates a new vlan device eth0.10 on device eth0.

       ip link delete dev eth0.10
           Removes vlan device.

       ip link help gre
           Display help for the gre link type.

       ip link add name tun1 type ipip remote 192.168.1.1 local
       192.168.1.2 ttl 225 encap gue encap-sport auto encap-dport 5555
       encap-csum encap-remcsum
           Creates an IPIP that is encapsulated with Generic UDP
           Encapsulation, and the outer UDP checksum and remote checksum
           offload are enabled.

       ip link set dev eth0 xdp obj prog.o
           Attaches a XDP/BPF program to device eth0, where the program
           is located in prog.o, section "prog" (default section). In
           case a XDP/BPF program is already attached, throw an error.

       ip -force link set dev eth0 xdp obj prog.o sec foo
           Attaches a XDP/BPF program to device eth0, where the program
           is located in prog.o, section "foo". In case a XDP/BPF program
           is already attached, it will be overridden by the new one.

       ip -force link set dev eth0 xdp pinned /sys/fs/bpf/foo
           Attaches a XDP/BPF program to device eth0, where the program
           was previously pinned as an object node into BPF file system
           under name foo.

       ip link set dev eth0 xdp off
           If a XDP/BPF program is attached on device eth0, detach it and
           effectively turn off XDP for device eth0.

       ip link add link wpan0 lowpan0 type lowpan
           Creates a 6LoWPAN interface named lowpan0 on the underlying
           IEEE 802.15.4 device wpan0.

       ip link add dev ip6erspan11 type ip6erspan seq key 102 local
       fc00:100::2 remote fc00:100::1 erspan_ver 2 erspan_dir ingress
       erspan_hwid 17
           Creates a IP6ERSPAN version 2 interface named ip6erspan00.

       ip link set dev swp0 type dsa conduit eth1
           Changes the conduit interface of the swp0 user port to eth1.

AUTHOR top

       Original Manpage by Michail Litvak <mci@owl.openwall.com>

COLOPHON top

       This page is part of the iproute2 (utilities for controlling
       TCP/IP networking and traffic) project.  Information about the
       project can be found at 
       ⟨http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2⟩.
       If you have a bug report for this manual page, send it to
       netdev@vger.kernel.org, shemminger@osdl.org.  This page was
       obtained from the project's upstream Git repository
       ⟨https://git.kernel.org/pub/scm/network/iproute2/iproute2.git⟩ on
       2025-02-02.  (At that time, the date of the most recent commit
       that was found in the repository was 2025-01-21.)  If you discover
       any rendering problems in this HTML version of the page, or you
       believe there is a better or more up-to-date source for the page,
       or you have corrections or improvements to the information in this
       COLOPHON (which is not part of the original manual page), send a
       mail to man-pages@man7.org

iproute2                       13 Dec 2012                     IP-LINK(8)

Pages that refer to this page: veth(4), network_namespaces(7), ip(8), ip-macsec(8), ip-stats(8), ip-vrf(8), wg(8), wg-quick(8)

ip-link(8) — Linux manual page

NAME top

SYNOPSIS top

DESCRIPTION top

EXAMPLES top

SEE ALSO top

AUTHOR top

COLOPHON top