ip command provided by the iproute package is used to adjust addresses, link state, routing tables, neighbour objects, and manage a system’s network components. The ip command is a powerful tool designed to replace many of the old net-tools commands still in use like ifconfig. Below is a command line reference/cheat sheet of the ‘ip’ command.
IP QUERIES
addr
: Display IP Addresses and property information (abbreviation of address)
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip addr | Show information for all addresses |
ip addr show dev em1 | Display information only for device em1 |
link
: Manage and display the state of all network interfaces
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip link | Show information for all interfaces |
ip link show dev em1 | Display information only for device em1 |
ip -s link | Display interface statistics |
route
: Display and alter the routing table.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip route | List all of the route entries in the kernel |
maddr
: Manage and display multicast IP addresses.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip maddr | Display multicast information for all devices |
ip maddr show dev em1 | Display multicast information for device em1 |
neigh
: Show neighbour objects; also known as the ARP table for IPv4
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip neigh | Display neighbour objects |
ip neigh show dev em1 | Show the ARP cache for device em1 |
MODIFYING ADDRESS AND LINK PROPERTIES
addr add
: Add an address.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip addr add 192.168.1.1/24 dev em1 | Add address 192.168.1.1 with netmask 24 to device em1 |
addr del
: Delete an address.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip addr del 192.168.1.1/24 dev em1 | Remove address 192.168.1.1/24 from device em1 |
link set
: Alter the status of the interface.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip link set em1 up | Bring em1 online |
ip link set em1 down | Bring em1 offline |
ip link set em1 mtu 9000 | Set the MTU on em1 to 9000 |
ip link set em1 promisc on | Enable promiscuous mode for em1 |
ADJUSTING AND VIEWING ROUTES
route add
: Add an entry to the routing table.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip route add default via 192.168.1.1 dev em1 | Add a default route (for all addresses) via the local gateway 192.168.1.1 that can be reached on device em1 |
ip route add 192.168.1.0/24 via 192.168.1.1 | Add a route to 192.168.1.0/24 via the gateway at 192.168.1.1 |
ip route add 192.168.1.0/24 dev em1 | Add a route to 192.168.1.0/24 that can be reached on device em1 |
route delete
: Delete a routing table entry.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip route delete 192.168.1.0/24 via 192.168.1.1 | Delete the route for 192.168.1.0/24 via the gateway at 192.168.1.1 |
route replace
: Replace, or add if not defined, a route.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip route replace 192.168.1.0/24 dev em1 | Replace the defined route for 192.168.1.0/24 to use device em1 |
route get
: Display the route an address will take.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip route get 192.168.1.5 | Display the route taken for IP 192.168.1.5 |
MANAGING THE ARP TABLE
neigh add
: Add an entry to the ARP Table.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip neigh add 192.168.1.1 lladdr 1:2:3:4:5:6 dev em1 | Add address 192.168.1.1 with MAC 1:2:3:4:5:6 to em1 |
neigh del
: Invalidate an entry.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip neigh del 192.168.1.1 dev em1 | Invalidate the entry for 192.168.1.1 on em1 |
neigh replace
: Replace, or adds if not defined, an entry to the ARP table.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip neigh replace 192.168.1.1 lladdr 1:2:3:4:5:6 dev em1 | Replace the entry for address 192.168.1.1 to use MAC 1:2:3:4:5:6 on em1 |
MULTICAST ADDRESSING
maddr add
: Add a static link-layer multicast address.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip maddr add 33:33:00:00:00:01 dev em1 | Add mutlicast address 33:33:00:00:00:01 to em1 |
maddr del
: Delete a multicast address.
SUBCOMMAND | DESCRIPTIONS AND TASKS |
---|---|
ip maddr del 33:33:00:00:00:01 dev em1 | Delete address 33:33:00:00:00:01 from em1 |