Master Linux Network Management with the Powerful ip Command

ip Command Basics

The ip command is part of the iproute2 suite and is used to display and manipulate routing tables, network interfaces, and tunnels. Its general syntax is ip [OPTIONS] OBJECT COMMAND where OBJECT can be link, addr, route, etc., and COMMAND includes actions such as add, del, show.

Viewing Network Interfaces

Show all interfaces: ip link show Show a specific interface (e.g., eth0):

ip link show dev eth0

Enabling and Disabling Interfaces

Enable: ip link set dev eth0 up Disable:

ip link set dev eth0 down

Configuring IP Addresses

Add an address: ip addr add 192.168.1.10/24 dev eth0 Delete an address: ip addr del 192.168.1.10/24 dev eth0 Show all addresses: ip addr show Show addresses on a specific device:

ip addr show dev eth0

Managing Routes

Show routing table: ip route show Add a route: ip route add 192.168.1.0/24 via 192.168.1.1 Delete a route: ip route del 192.168.1.0/24 Add default route:

ip route add default via 192.168.1.1

Configuring Network Aliases

Add an alias:

ip addr add 192.168.1.20/24 dev eth0 label eth0:1

Show aliases:

ip addr show dev eth0

Managing ARP Cache

Show ARP entries: ip neigh show Add a static ARP entry:

ip neigh add 192.168.1.10 lladdr 00:11:22:33:44:55 dev eth0

Delete an ARP entry:

ip neigh del 192.168.1.10 dev eth0

VLAN Configuration

Create a VLAN interface:

ip link add link eth0 name eth0.100 type vlan id 100

Delete a VLAN interface:

ip link delete eth0.100

Summary

The Linux ip command is a powerful and flexible tool for network management, covering everything from basic interface configuration to advanced routing and VLAN handling. Mastering these common operations enables efficient administration and troubleshooting of Linux network environments.