IP-LINK(8) Linux IP-LINK(8)
NAME
ip-link - network device configuration
SYNOPSIS
ip [ OPTIONS ] link { COMMAND | help }
OPTIONS := { -V[ersion] | -h[uman-readable] | -s[tatistics] | -r[esolve] | -f[amily] {
inet | inet6 | ipx | dnet | link } | -o[neline] | -br[ief] }
ip link add [ link DEVICE ] [ name ] NAME
[ txqueuelen PACKETS ]
[ address LLADDR ] [ broadcast LLADDR ]
[ mtu MTU ] [ index IDX ]
[ numtxqueues QUEUE_COUNT ] [ numrxqueues QUEUE_COUNT ]
type TYPE [ ARGS ]
TYPE := [ bridge | bond | can | dummy | hsr | ifb | ipoib | macvlan | macvtap | vcan |
veth | vlan | vxlan | ip6tnl | ipip | sit | gre | gretap | ip6gre | ip6gretap |
vti | nlmon | ipvlan | lowpan | geneve ]
ip link delete { DEVICE | group GROUP } type TYPE [ ARGS ]
ip link set { DEVICE | group GROUP } { up | down | arp { on | off } |
promisc { on | off } |
allmulticast { on | off } |
dynamic { on | off } |
multicast { on | off } |
protodown { on | off } |
txqueuelen PACKETS |
name NEWNAME |
address LLADDR | broadcast LLADDR |
mtu MTU |
netns PID |
netns NETNSNAME |
alias NAME |
vf NUM [ mac LLADDR ] [ vlan VLANID [ qos VLAN-QOS ] ] [ rate TXRATE ] [
max_tx_rate TXRATE ] [ min_tx_rate TXRATE ] [ spoofchk { on | off } ] [ state {
auto | enable | disable} ] |
master DEVICE |
nomaster |
addrgenmode { eui64 | none }
link-netnsid ID }
ip link show [ DEVICE | group GROUP | up | master DEVICE | type TYPE ]
ip link help [ TYPE ]
DESCRIPTION
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:
bridge - Ethernet Bridge device
bond - Bonding device can - Controller Area Network interface
dummy - Dummy network interface
hsr - High-availability Seamless Redundancy device
ifb - Intermediate Functional Block device
ipoib - IP over Infiniband device
macvlan - Virtual interface base on link layer address (MAC)
macvtap - Virtual interface based on link layer address (MAC) and TAP.
vcan - Virtual Controller Area Network interface
veth - Virtual ethernet interface
vlan - 802.1q tagged virtual LAN interface
vxlan - Virtual eXtended LAN
ip6tnl - Virtual tunnel interface IPv4|IPv6 over IPv6
ipip - Virtual tunnel interface IPv4 over IPv4
sit - Virtual tunnel interface IPv6 over IPv4
gre - Virtual tunnel interface GRE over IPv4
gretap - Virtual L2 tunnel interface GRE over IPv4
ip6gre - Virtual tunnel interface GRE over IPv6
ip6gretap - Virtual L2 tunnel interface GRE over IPv6
vti - Virtual tunnel interface
nlmon - Netlink monitoring device
ipvlan - Interface for L3 (IPv6/IPv4) based VLANs
lowpan - Interface for 6LoWPAN (IPv6) over IEEE 802.15.4 / Bluetooth
geneve - GEneric NEtwork Virtualization Encapsulation
numtxqueues QUEUE_COUNT
specifies the number of transmit queues for new device.
numrxqueues QUEUE_COUNT
specifies the number of receive queues for new device.
index IDX
specifies the desired index of the new virtual device. The link creation fails, if
the index is busy.
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 } ] [ ingress-qos-map QOS-MAP ] [ egress-qos-map QOS-MAP ]
protocol VLAN_PROTO - either 802.1Q or 802.1ad.
id VLANID - specifies the VLAN Identifer to use. Note that numbers with a
leading " 0 " or " 0x " are interpreted as octal or hexadeimal, respec‐
tively.
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 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 | grep tx-vlan-offload
where 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.
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 prior‐
ity 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 ID [ dev PHYS_DEV ] [ { group | remote } IPADDR ]
[ local IPADDR ] [ ttl TTL ] [ tos TOS ] [ dstport PORT ] [ srcport MIN MAX ] [
[no]learning ] [ [no]proxy ] [ [no]rsc ] [ [no]l2miss ] [ [no]l3miss ] [ [no]udpc‐
sum ] [ [no]udp6zerocsumtx ] [ [no]udp6zerocsumrx ] [ ageing SECONDS ] [ maxaddress
NUMBER ] [ gbp ]
id VNI - specifies the VXLAN Network Identifer (or VXLAN Segment Identi‐
fier) 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 out‐
going 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.
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 filled in
[no]udp6zerocsumtx - specifies if UDP checksum is filled in
[no]udp6zerocsumrx - specifies if UDP checksum is received
ageing SECONDS - specifies the lifetime in seconds of FDB entries learnt by
the kernel.
maxaddress NUMBER - specifies the maximum number of FDB entries.
gbp - enables the Group Policy extension (VXLAN-GBP).
Allows to transport group policy context across VXLAN network peers.
If enabled, includes the mark of a packet in the VXLAN header for out‐
going packets and fills the packet mark based on the information found
in the VXLAN header for incomming 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
GRE, IPIP, SIT Type Support
For a link of types GRE/IPIP/SIT the following additional arguments are supported:
ip link add DEVICE type { gre | ipip | sit } remote ADDR local ADDR [ encap { fou
| gue | none } ] [ encap-sport { PORT | auto } ] [ encap-dport PORT ] [ [no]encap-
csum ] [ [no]encap-remcsum ]
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 encapsula‐
tion. 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.
IP6GRE/IP6GRETAP Type Support
For a link of type IP6GRE/IP6GRETAP the following additional arguments are sup‐
ported:
ip link add DEVICE type { ip6gre | ip6gretap } remote ADDR local ADDR [ [i|o]seq]
] [ [i|o]key KEY ] [ [i|o]csum ] [ hoplimit TTL ] [ encaplimit ELIM ] [ tclass
TCLASS ] [ flowlabel FLOWLABEL ] [ dscp inherit ] [ dev PHYS_DEV ]
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.
[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 - 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.
[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 equiva‐
lent to the combination icsum ocsum.
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.
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 pre‐
defined 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.
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.
GENEVE Type Support
For a link of type GENEVE the following additional arguments are supported:
ip link add DEVICE type geneve id ID remote IPADDR [ ttl TTL ] [ tos TOS ]
id VNI - specifies the Virtual Network Identifer to use.
remote IPADDR - specifies the unicast destination IP address to use in out‐
going packets.
ttl TTL - specifies the TTL value to use in outgoing packets.
tos TOS - specifies the TOS value to use in outgoing packets.
MACVLAN and MACVTAP Type Support
For a link of type MACVLAN or MACVTAP the following additional arguments are sup‐
ported:
ip link add link DEVICE name NAME type { macvlan | macvtap } mode { private | vepa
| bridge | passthru [ nopromisc ] }
type { macvlan | macvtap } - specifies the link type to use. macvlan cre‐
ates just a virtual interface, while macvtap in addition creates a charac‐
ter 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 end‐
point, usually in macvtap mode. It is not allowed for more than one end‐
point 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.
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
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.
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.
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 NETNSNAME | PID
move the device to the network namespace associated with name NETNSNAME or process
PID.
Some devices are not allowed to change network namespace: loopback, bridge, ppp,
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 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 file
/etc/iproute2/group.
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 speci‐
fied, 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 spec‐
ified, all VLAN tags transmitted by the VF will include the specified pri‐
ority 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.
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. 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. vf parameter must be specified.
spoofchk on|off - turn packet spoof checking on or off for the specified
VF.
state auto|enable|disable - set the virtual link state as seen by the spec‐
ified 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.
master DEVICE
set master device of the device (enslave device).
nomaster
unset master device of the device (release device).
addrgenmode eui64 or addrgenmode none
set IPv6 address generation mode
link-netnsid
set peer netnsid for a cross-netns interface
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 unpre‐
dictable state. The solution is to avoid changing several parameters with one ip link set
call.
ip link show - display device attributes
dev NAME (default)
NAME specifies the network device to show. If this argument is omitted all devices
in the default group are listed.
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.
type TYPE
TYPE specifies the type of devices to show.
The show command has additional formatting options:
-s, -stats, -statistics
output more statistics about packet usage.
-d, -details
output more detailed information.
-h, -human, -human-readable
output statistics with human readable values number followed by suffix
-iec print human readable rates in IEC units (ie. 1K = 1024).
ip link help - display help
TYPE specifies which help of link type to dislpay.
GROUP
may be a number or a string from the file /etc/iproute2/group which can be manually
filled.
EXAMPLES
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 add link wpan0 lowpan0 type lowpan
Creates a 6LoWPAN interface named lowpan0 on the underlying IEEE 802.15.4 device
wpan0.
SEE ALSO
ip(8), ip-netns(8), ethtool(8), iptables(8)
AUTHOR
Original Manpage by Michail Litvak
iproute2 13 Dec 2012 IP-LINK(8)
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