my-docs/Linux/LPIC1/20-ip.md

🌐 IP Command Cheat Sheet

The ip command is a powerful tool for network configuration and management in Linux. It replaces many of the older ifconfig functionalities.

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📌 General Syntax

ip [ OPTIONS ] OBJECT { COMMAND | help }

Common OBJECTS:

• addr – IP addresses
• link – Network interfaces
• route – Routing tables
• neigh – ARP table
• rule, netns, etc.

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🔍 View Network Information

Show All IP Addresses

ip addr show
# or shorthand:
ip a

Show IP for Specific Interface

ip addr show dev eth0

Show Link Layer Information

ip link show

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🔧 Interface Management

Bring Interface Down

ip link set eth0 down

Bring Interface Up

ip link set eth0 up

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🌐 IP Address Configuration

Add an IP Address

ip addr add 192.168.1.10/24 dev eth0

Delete an IP Address

ip addr del 192.168.1.10/24 dev eth0

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🛣️ Routing

Show Routing Table

ip route show

Add a Default Gateway

ip route add default via 192.168.1.1

Add a Specific Route

ip route add 192.168.10.0/24 via 192.168.5.2

Delete a Specific Route

ip route del 192.168.10.0/24 via 192.168.5.2

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🧱 Bridge Interface Management

Create a Bridge

ip link add name br0 type bridge

Delete a Bridge

ip link delete br0

Bring Bridge Up

ip link set br0 up

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🛠️ Example: Set a Static IP Address

ip link set ens33 up
ip addr add 10.10.40.12/24 dev ens33
ip route add default via 10.10.40.1

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✅ Tip:

Always verify with:

ip a
ip r