Understanding the ifconfig Command

Basic Usage of ifconfig

The ifconfig command is used to configure and display network interface parameters for a Linux system. It allows users to view network interface information and manage network configurations.

Options Available with ifconfig

interface

Specify the network interface to configure or display. For example, eth0, wlan0, etc.

up

Activate the specified interface:

down

Deactivate the specified interface:

inet address

Assign an IP address to the specified interface:

netmask mask

Assign a netmask to the specified interface:

broadcast address

Assign a broadcast address to the specified interface:

hw ether address

Change the hardware (MAC) address of the interface:

mtu size

Set the Maximum Transmission Unit (MTU) size:

-a

Show all interfaces, including those that are down:

-s

Display a short summary of the network interfaces:

-h

Display help information for the command:

Examples of ifconfig Command

Display Network Interfaces

This command displays all active network interfaces and their configurations.

Activate a Network Interface

This command activates the eth0 interface.

Deactivate a Network Interface

This command deactivates the eth0 interface.

Set an IP Address

This command assigns the IP address 192.168.1.100 to the eth0 interface with the specified netmask.

Understanding ifconfig Output

The output of the ifconfig command typically includes the following information:

• Interface Name: The name of the network interface (e.g., eth0, wlan0).
• inet: The assigned IP address for the interface.
• netmask: The netmask associated with the IP address.
• broadcast: The broadcast address for the network.
• ether: The hardware (MAC) address of the interface.
• RX packets: The number of packets received.
• TX packets: The number of packets transmitted.

Summary of Options