IP command is similar to ifconfig, which is very familiar for assigning Static IP Address, Route, Default Gateway, and configure network interface parameters on Linux system.
IP command replaces the ifconfig command on modern Linux distributions because it does not support InfiniBand addresses. However it is still available on most Linux distributions.
IP command utility bundled with ‘iproute2’ package. By default iproute2 utility pre-installed in most of the major Linux distributions. If no, you can install it by issuing iproute2 on your terminal with help of your system package manager.
Be careful when using the IP command on a remote Linux system, because if you make a mistake you will lose the connection with the server.
By default, the changes you make through the IP command will not be permanent until you update the parameters in the configuration file. If you do not make them permanent the system will not retain changes when the system restarts.
In this guide, we’ll show you how to use the IP command when configuring the network interface in Linux.
IP command general syntax as follows:
Syntax: $ ip OBJECT COMMAND $ ip [options] OBJECT COMMAND $ ip OBJECT help $ ip [options] OBJECT COMMAND [parameters]
Before seeing the IP command usage, you should understand the IP command ‘OBJECTS’ and their purpose so, that the right option can be used in the right place.
| OBJECT | Abbreviated Form | Description |
|---|---|---|
| link | l | Display and modify network interfaces |
| address | a, addr | Display and modify IP Addresses |
| addrlabel | addrl | Label configuration for protocol address selection |
| neighbour | n, neigh | ARP or NDISC cache entry |
| route | r | Display and alter the routing table |
| rule | ru | Rule in routing policy database |
| maddress | m, maddr | Multicast address |
| mroute | mr | Multicast routing cache entry |
| tunnel | t | Tunnel over IP |
Make a note: When configuring network interfaces, you must execute the ip command as root or user with sudo privileges, otherwise you will get an error.
Display information about all network interfaces
To display a list of available all network interfaces (active or inactive) and the associated ip address, run:
It shows many information for each interface not only IP address.
$ ip a
or
$ ip addr
or
$ ip address
or
$ ip addr show
1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: mtu 1500 qdisc pfifo_fast state DOWN group default qlen 1000
link/ether c8:5b:76:4d:d4:5c brd ff:ff:ff:ff:ff:ff
3: wlan0: mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether e4:a7:a0:32:fc:e9 brd ff:ff:ff:ff:ff:ff
inet 192.168.43.4/24 brd 192.168.43.255 scope global dynamic noprefixroute wlan0
valid_lft 2786sec preferred_lft 2786sec
inet6 2402:3a80:569:5fbd:d9d1:87d8:dac7:75c5/64 scope global temporary dynamic
valid_lft 3587sec preferred_lft 3587sec
inet6 2402:3a80:569:5fbd:6be2:c0c4:6e5e:d29b/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 3587sec preferred_lft 3587sec
inet6 fe80::e5e8:a342:f161:a8d4/64 scope link noprefixroute
valid_lft forever preferred_lft forever
You can find the following information from the above output.
- It shows list of available interfaces (including active and inactive) on the system.
- IP address (IPv4 and IPv6), MAC address, subnet mask, and mtu value of the interface.
- The interface has either a static IP or a dynamic IP. If it’s configured via DHCP (Dynamic IP), the interface output displays the word
"dynamic". - You can determine if the interface is Ethernet or WiFi using the naming convention standard. Ethernet interfaces always start with the letter
'e'whereas Wi-Fi interfaces always start with the letter'w'.
Show information about a specific network interface
To display information about a specific network interface, enter the device name with the IP command. For instance, to view 'wlan0', you would run. Similarly, you can view any interface information.
$ ip addr show eth0
or
$ ip addr list eth0
or
$ ip addr show dev eth0
3: wlan0: mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether e4:a7:a0:32:fc:e9 brd ff:ff:ff:ff:ff:ff
inet 192.168.43.4/24 brd 192.168.43.255 scope global dynamic noprefixroute wlan0
valid_lft 2782sec preferred_lft 2782sec
inet6 2402:3a80:569:5fbd:d9d1:87d8:dac7:75c5/64 scope global temporary dynamic
valid_lft 3583sec preferred_lft 3583sec
inet6 2402:3a80:569:5fbd:6be2:c0c4:6e5e:d29b/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 3583sec preferred_lft 3583sec
inet6 fe80::e5e8:a342:f161:a8d4/64 scope link noprefixroute
valid_lft forever preferred_lft forever
Show only information about IPv4 or IPv6
If you only want to view 'IPv4' or 'IPv6' information, you can do this by using the following options with the ip command:
To list the IPv4 addresses, run:
$ ip -4 addr
1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
3: wlan0: mtu 1500 qdisc noqueue state UP group default qlen 1000
inet 192.168.43.4/24 brd 192.168.43.255 scope global dynamic noprefixroute wlan0
valid_lft 2403sec preferred_lft 2403sec
To list the IPv6 addresses, run:
$ ip -6 addr
1: lo: mtu 65536 state UNKNOWN qlen 1000
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
3: wlan0: mtu 1500 state UP qlen 1000
inet6 2402:3a80:569:5fbd:d9d1:87d8:dac7:75c5/64 scope global temporary dynamic
valid_lft 3569sec preferred_lft 3569sec
inet6 2402:3a80:569:5fbd:6be2:c0c4:6e5e:d29b/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 3569sec preferred_lft 3569sec
inet6 fe80::e5e8:a342:f161:a8d4/64 scope link noprefixroute
valid_lft forever preferred_lft forever
Assigning a Static IP Address to an Interface
The ip command can be used to assign IP addresses to an interface. Use the following syntax to assign a IP address to a specific interface.
Syntax: ip addr add address dev ifname address: The IP address you want to assign to the interface, which must be included with netmask. ifname : Specifies the interface from which you want to add the IP.
For instance, to add address 10.20.0.15 with netmask 24 to device ‘eth1’, you would run:
$ sudo ip addr add 10.20.0.15/24 dev eth1
Configuring multiple IP addresses
You can assign multiple IP addresses to the same interface without using the alias interface as shown below. The same IP command can be used multiple times to assign multiple addresses to a single interface.
$ sudo ip address add 10.20.0.15/24 dev eth1
$ sudo ip address add 10.20.0.16/24 dev eth1
You can see the output similar to the below:
$ ip -4 addr show eth0
2: eth0: mtu 1500 qdisc fq_codel state UP group default qlen 1000
inet 10.20.0.15/24 brd 10.20.0.255 scope global dynamic eth1
valid_lft 3569sec preferred_lft 3569sec
inet 10.20.0.16/24 scope global secondary eth1
valid_lft forever preferred_lft forever
Remove an IP address from the interface
The following IP command syntax can be used to remove an IP address from a specific interface.
Syntax: ip addr del ADDRESS dev IFNAME
For example: To remove address ‘10.20.0.15/24’ from device ‘eth1’, run:
$ sudo ip addr del 10.20.0.15/24 dev eth1
Enable the Network Interface
To bring interfaces up or down, use the following IP command syntax:
Syntax: ip link set dev [DEVICE] [up]
For instance, to bring up the interface ‘eth1’ online, run:
$ sudo ip link set dev eth1 up
Bring down the Network Interface
Use the following IP command syntax to bring down the interfaces.
Syntax: ip link set dev [DEVICE] [down]
For instance, to bring down the interface ‘eth1’ offline, run:
$ sudo ip link set dev eth1 down
Changing the txqueuelen of the device
IP command can be used to set the length of the transmit queue of the device as shown below:
Syntax: ip link set txqueuelen [NUMBER] dev [DEVICE]
Changing the MTU of the device
You can set maximum transmission units (MTU) for better network performance as shown below:
Syntax: ip link set mtu [NUMBER] dev [DEVICE]
Display and alter the routing table
IP command can be used to alter and view routing table information on the Linux system using the ‘route’ object.
Display routing table
Run one of the following command to check the routing table information of the system.
$ ip r or $ ip route or $ ip route show or $ ip route list default via 192.168.43.1 dev wlan0 proto dhcp metric 600 192.168.43.0/24 dev wlan0 proto kernel scope link src 192.168.43.4 metric 600
To make the gateway permanent, you must add the gateway value to the interface configuration file or update the interface routing configuration file, as mentioned below:
All network interface related configuration files can be found at ‘/etc/sysconfig/network-scripts/’.
- ifcfg-enp0s3 – Network interface configuration file of enp0s3 interface.
- route-enp0s3 – Create a new file with ‘route-IFNAME’ then add a route information.
Adding a new route
To add a route via gateway, use the following syntax:
Syntax:
ip route add [network/mask] via [gatewayIP]
Add a new route to 10.20.0.0/24 via the gateway at 10.20.0.1, run:
$ sudo ip route add 10.20.0.0/24 via 10.20.0.1
To add a route through a device (network interface), use the following syntax:
Syntax: ip route add [network/mask] dev [IFNAME]
Add a new route to 10.20.0.0/24 that can be reached on device eth1.
$ sudo ip route add 10.20.0.0/24 dev eth1
You must use the keyword ‘default’ in the IP route command to make the route as default. For example, to add a default route via the local gateway 10.20.0.1 that can be reached on device eth1, run:
$ sudo ip route add default via 10.20.0.1 dev eth1
Delete a route
Use the following command to delete default gateway.
$ sudo ip route del default
Use the following syntax to delete the route added via gateway IP.
Syntax: ip route del [network/mask] via [gatewayIP] $ sudo ip route del 10.20.0.0/24 via 10.20.0.1
Use the following syntax to remove the route added through a device (network interface).
Syntax: ip route del [network/mask] dev [IFNAME] $ sudo ip route del 10.20.0.0/24 dev eth1
Show Network Statistics
IP command is not limited to do IP manipulation, also shows network statistics, Use the following command to check network statistics for all interfaces.
$ ip -s link
1: lo: mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
RX: bytes packets errors dropped overrun mcast
46440 448 0 0 0 0
TX: bytes packets errors dropped carrier collsns
46440 448 0 0 0 0
2: eth0: mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 1000
link/ether c8:5b:76:4d:d4:5c brd ff:ff:ff:ff:ff:ff
RX: bytes packets errors dropped overrun mcast
0 0 0 0 0 0
TX: bytes packets errors dropped carrier collsns
0 0 0 0 0 0
4: wlan0: mtu 1500 qdisc noqueue state UP mode DORMANT group default qlen 1000
link/ether e4:a7:a0:32:fc:e9 brd ff:ff:ff:ff:ff:ff
RX: bytes packets errors dropped overrun mcast
43779183 60701 0 0 0 0
TX: bytes packets errors dropped carrier collsns
12447326 54365 0 0 0 0
Show specific Network interface Statistics
Add the desired network interface name to Show specific Network interface Statistics.
$ ip -s link ls wlan0
4: wlan0: mtu 1500 qdisc noqueue state UP mode DORMANT group default qlen 1000
link/ether e4:a7:a0:32:fc:e9 brd ff:ff:ff:ff:ff:ff
RX: bytes packets errors dropped overrun mcast
43782833 60729 0 0 0 0
TX: bytes packets errors dropped carrier collsns
12452566 54396 0 0 0 0
Closing Notes
In this guide, we’ve shown you several IP command examples to add, delete and modify IP address, routing table & other information in Linux.
If you have any questions or feedback, feel free to comment below.
