ip-link

network device configuration: bring interfaces up/down, set MAC, MTU, create virtual links

TLDR

Show all interfaces

$ ip link

Show specific interface

$ ip link show eth0

Show detailed statistics

$ ip -s link show eth0

Bring interface up/down

$ sudo ip link set eth0 up

Set alias name

$ sudo ip link set eth0 alias "LAN Interface"

Change MAC address (interface must be down)

$ sudo ip link set dev eth0 address ff:ee:dd:cc:bb:aa

Set MTU size

$ sudo ip link set eth0 mtu 9000

Set promiscuous mode

$ sudo ip link set eth0 promisc on

Create a VLAN sub-interface

$ sudo ip link add link eth0 name eth0.10 type vlan id 10

SYNOPSIS

ip [OPTIONS] link COMMAND [arguments]

ip link manages network devices. It can list interfaces, change their state and parameters (MAC address, MTU, alias, promiscuous mode), and create or delete virtual links such as bridges, bonds, VLANs, VXLANs, dummies, veth pairs, and tun/tap devices.It is part of the iproute2 suite that replaces the older ifconfig utility.

PARAMETERS

show [device]

Display interface information. Without device, all interfaces are shown. Combine with -s for statistics, -d for detailed driver info.

set device

Modify properties of an existing interface.

add [link DEV] name NAME type TYPE

Create a virtual interface of the given type (bridge, vlan, veth, dummy, bond, vxlan, ...).

delete device

Remove a virtual interface.

up | down

Bring the interface administratively up or down.

address LLADDR

Set the link-layer (MAC) address. Usually requires the interface to be down first.

mtu BYTES

Set the Maximum Transmission Unit.

alias NAME

Set a human-readable interface description.

promisc on | off

Enable or disable promiscuous mode.

multicast on | off

Enable or disable multicast reception.

arp on | off

Enable or disable ARP on the interface.

master DEVICE

Enslave the interface to a master (bridge or bond).

nomaster

Detach the interface from its master.

txqueuelen N

Set the transmit queue length.

netns PID | NAME

Move the interface into the given network namespace.

INSTALL

sudo apt install iproute2

sudo pacman -S iproute2

sudo apk add iproute2-minimal

sudo zypper install iproute2

brew install iproute2

nix profile install nixpkgs#iproute2

CAVEATS

Changing the MAC address usually requires the interface to be brought down first. Virtual interfaces created with ip link add are not persistent across reboots unless declared in distribution-specific network configuration (NetworkManager, systemd-networkd, /etc/network/interfaces, etc.). Some operations require CAP_NET_ADMIN (typically root).

HISTORY

ip link is part of iproute2, originally written by Alexey Kuznetsov and now maintained by Stephen Hemminger. It supersedes the deprecated ifconfig command from net-tools.