Linux ip Command with Examples

Introduction

The ip command is a Linux networking tool for configuring network interfaces. It was designed to extend the functionality and simplify the syntax of the older ifconfig command, which is still present on some systems as part of the net-tools package.

This tutorial introduces the ip command, lists examples of its usage, and provides a downloadable PDF cheat sheet for quick reference.

Prerequisites

• Command-line access.
• Administrative privileges.
• The iproute2 package installed.

Linux ip Command Syntax

The ip command accepts objects (subcommands), options, and additional arguments, allowing users to configure and manage network interfaces, routes, tunneling, etc. Below is the basic command syntax:

ip [option] [subcommand] [arguments]

The following list introduces the most frequently used ip command objects:

• link (l) configures network interfaces.
• address (addr/a) modifies protocol addresses (IP, IPv6).
• route (r) alters routing tables.
• neigh (n) manipulates neighbor objects.

The commands can be executed using either full or abbreviated object forms. For example, ip link and ip l will give the same results.

To see a complete list of ip objects, type in the following command:

ip help

ip vs. ifconfig

The ip and ifconfig commands are used for network interface configuration in Linux. However, ip provides additional functionalities and a more consistent syntax. The list below contains the main points of comparison between ip and ifconfig:

• ifconfig is part of the older net-tools package that is not actively maintained. ip belongs to the newer iproute2 package.
• ifconfig uses ioctl system calls to communicate with the kernel while ip uses more efficient Netlink sockets.
• ifconfig syntax is simple but lacks consistency. ip features more consistent hierarchical syntax.
• While ifconfig focuses on network interface configuration, ip adds the possibility of route, address, and tunnel management.
• ifconfig has limited support for the IPv6 protocol, while ip supports it fully.
• ifconfig displays enabled interfaces only. ip can show both enabled and disabled interfaces.

Linux ip Command Options

The ip command options change the command's behavior, control the information the command provides, and format the output to make it more readable. The table below lists all the available options:

Option	Description
-a, -all	Executes the command on all objects (supported commands only).
-b, -batch	Allows the user to provide a batch file with multiple commands and executes them all.
-br, -brief	Prints essential information only.
-c	Shows color output.
-d, -details	Prints detailed information.
-echo	Requests the kernel to echo back the applied configuration.
-f, -family	Allows the user to specify the protocol family. Available options are inet, inet6, bridge, mpls, and link. Each family has a shortcut: -4 is short for -family inet, -6 is -family inet6, -B stands for -family bridge, -M for -family mpls, and -0 for -family link.
-force	In batch mode, continues executing ip even if there are errors in the command execution.
-h, -human, -human-readable	Prints stats with suffixed human-readable values.
-iec	Shows human-readable rates using IEC units.
-j, -json	Prints output using JSON format.
-l, -loops	Allows the user to set the maximum number of tries ip address flush should attempt before stopping.
-n, -netns	Switches the ip command to the NETNS network namespace.
-N, -Numeric	Prints numerical values for protocol, dsfield, scope, etc.
-o, -oneline	Uses one line per record.
-p, -pretty	Adds indentation in JSON documents.
-r, -resolve	Outputs DNS names instead of host addresses.
-rc, -rcvbuf	Sets the receive buffer size for the netlink socket.
-s, -stats, -statistics	Shows more information in the command output. Can be used multiple times within a single command to increase the amount of the information provided.
-t, -timestamp	Shows current time.
-ts, -tshort	Sets the receive buffer size for the Netlink socket.
-V, -Version	Prints the version of the ip utility.

ip Command Cheat Sheet

We compiled a list of the most frequently used commands and created a one-page downloadable PDF cheat sheet. Click the button below to download the cheat sheet and use it as a reference when working with the ip command.

ip Command Examples

The following sections provide an overview of the common ip command operations. The accompanying examples illustrate the use of the command and clarify the syntax.

Get Network Interface Information

Type the following command to see link-layer information for all devices that have a driver loaded:

ip link show

The output shows a numbered list of devices with their configuration parameters.

To see a list of running interfaces only, use the syntax below:

ip link ls up

To see information for one specific device:

ip link show dev [device]

For example, to view the device named enp0s3, enter:

ip link show dev enp0s3

The output shows enp0s3 information:

View Interface Statistics

To see statistics for all network interfaces, use the -s option:

ip -s link

The device list now displays details such as transferred packets, dropped packets, and errors.

To see this information for an individual network interface, enter the following:

ip -s link ls [interface]

For example, use the command below to view the statistics for the enp0s3 device:

ip -s link ls enp0s3

To print more detailed stats, add another -s to the syntax:

ip -s -s link ls enp0s3

The output now features dedicated lines for RX and TX errors.

Disable Interface (Offline)

Use the link object to enable or disable network interfaces. For example, to disable the previously mentioned enp0s3 interface, enter:

sudo ip link set enp0s3 down

If successful, the command produces no output. To see the results of the operation, list the available interfaces:

ip link show

The enp0s3 interface no longer shows the UP status, meaning it is disabled.

Enable Interface (Online)

The following command brings the disabled enp0s3 interface online:

ip link set enp0s3 up

The command produces no output unless an error occurs.

Modify Transmit Queue

Speeding up or slowing down a network interface is performed by modifying the transmit queue length (txqueuelen) number. By default, the txqueuelen number is 1000, corresponding to the number of frames that can be on the transmission queue. Change the txqueuelen number by using the following syntax:

sudo ip link set txqueuelen [number] dev [interface]

For example, type the following to increase the number of queued frames to 10000 on the enp0s3 device:

sudo ip link set txqueuelen 10000 dev enp0s3

The successful operation produces no output. Use ip link show to see the device's parameters:

ip link show dev enp0s3

The command output lists txqueuelen number as qlen.

Set Maximum Transmission Unit (MTU)

Another way to improve network performance is to adjust the Maximum Transmission Unit (MTU) number. It defines the number of bytes for the largest data packet, i.e., the network device rejects packets exceeding the MTU value.

The default MTU value is 1000. Type the command below to change the MTU number:

sudo ip link set mtu [number] dev [interface]

For example, enter the following to increase the MTU to 10000 on the enp0s3 device.

sudo ip link set mtu 10000 dev enp0s3

The command produces no output, but the change is visible in the output of the ip link show command:

ip link show dev enp0s3

Change MAC Address

The ip command provides a way to change the MAC address of an interface:

1. Disable the interface:

ip link set dev [interface] down

2. Change the MAC address:

ip link set dev [interface] address [mac_address]

3. Re-enable the interface:

ip link set dev [interface] up

Monitor IP Addresses 

Use the address object to list all network interfaces and the associated IP addresses:

ip addr

Alternatively, achieve the same result by adding the show subcommand:

ip addr show

Provide an interface name to view information about the specific network. For example, type the following to see info about the enp0s3 interface:

ip addr show dev enp0s3

Use the -4 option to list the IPv4 addresses only:

ip -4 addr

List only IPv6 addresses with the -6 option:

ip -6 addr

Add IP Address to Interface

Add an IP address to an existing interface by using the following syntax:

sudo ip addr add [ip_address] dev [interface]

The example below adds a 10.0.2.12 IP address to the enp0s3 interface:

sudo ip addr add 10.0.2.12 dev enp0s3

The added address is visible in the network interface list:

ip a

To add a broadcast address to an interface, use the command below:

sudo ip addr add brd [ip_address] dev [interface]

Remove IP Address from Interface

Remove an IP address from an interface by typing:

ip addr del [ip_address] dev [interface]

When typing the address, specify the prefix length (e.g., 10.0.2.12/32) to avoid a warning message. For example, to delete the IP address added in the previous section, enter:

ip addr del 10.0.2.12/32 dev enp0s3

Display IP Routing Table

The route object manages route entries on the system. View all the route entries using the following command:

ip route

Alternatively, use the list subcommand:

ip route list

Narrow down the search by adding the SELECTOR object:

ip route list [selector]

The following is a list of available selectors:

• root [prefix]
• match [prefix]
• exact [prefix]
• table [table_id]
• proto [rt_proto]
• type [type]
• scope [scope]

For example, the following command displays the local routing table, i.e., routes for addresses connected directly to the local machine:

ip route list table local

To view routing for a specific network, provide the network IP address as the argument to the ip route list command:

ip route list [ip_address]

Add New Entry to Routing Table

To add a static routing table entry to a specific device, enter the command below:

ip route add [ip_address] dev [interface]

To add a new route using a gateway address, type:

ip route add [ip_address] via [gateway_IP] dev [interface]

The command below sends all traffic for the 192.168.0.0/24 IP address on enp0s3 through the 192.168.0.254 gateway:

sudo ip route add 192.168.0.0/24 via 192.168.0.254 dev enp0s3

To make the rule default, add the default argument:

sudo ip route add default 192.168.0.0/24 via 192.168.0.254 dev enp0s3

Delete Existing Routing Table Entry

Delete an existing entry in a routing table by using the ip route del subcommand:

ip route del [ip_address]

To delete the default route, type:

ip route del default

Display IP Neighbor Entries

The ip neigh object manages neighbor tables. Display the available neighbor tables by entering:

ip neigh show

The output shows the MAC addresses and the state of devices in the system. A device entry can be in one of the following states:

• REACHABLE. A valid, reachable entry until the timeout expires.
• PERMANENT. An entry that remains in the cache indefinitely unless removed by an administrator.
• STALE. A valid but unreachable entry. Before sending packets to a stale neighbor, the system verifies the reachability.
• DELAY signifies that the kernel is still waiting for the stale entry validation.

Add or Remove ARP Table Entries

The neigh object allows the user to manually add an entry to the Address Resolution Protocol (ARP) table. Use the following syntax for this operation:

ip neigh add [ip_address] dev [interface]

To manually delete an ARP table entry, type:

ip neigh del [ip_address] dev [interface]

Print Colored Output

Use the -c option to color the output of any ip command. The following example shows how to color the output of the ip link command:

ip -c link

Conclusion

After reading this article, you know how to use the ip command to administer a network on a Linux system. The article also provided a downloadable PDF cheat sheet that helps you recall the essential ip commands.

Next, discover more Linux Commands in our Cheat Sheet and Tutorial With Examples.