cmd line tutorials - gencmd

cmd line tutorials - gencmd

The ifconfig Command

— Unix-Linux Mac

The ifconfig command is a network interface configuration utility that is used to configure and manage network interfaces on Unix-like operating systems. It is a powerful tool that can be used to perform a variety of tasks, such as:

  • Listing network interfaces.
  • Viewing the configuration of a network interface.
  • Enabling/disabling a network interface.
  • Changing the IP address of a network interface.
  • Configuring routing tables.

Syntax

The basic syntax for the ifconfig command is as follows:

ifconfig [interface] [options]

The interface argument is the name of the network interface that you want to configure or manage. If you do not specify an interface, the ifconfig command will list all of the network interfaces on the system.

The options argument is a list of options that can be used to modify the behavior of the ifconfig command.

Examples

List all of the network interfaces on the system:

ifconfig

Display the configuration of the network interface eth0:

ifconfig eth0

Enable the network interface eth0:

ifconfig eth0 up

Disable the network interface eth0:

ifconfig eth0 down

Change the IP address of the network interface eth0 to 192.168.1.100:

ifconfig eth0 192.168.1.100

Add a route to the network 192.168.0.0/24 through the gateway 192.168.1.1:

ifconfig eth0 add 192.168.0.0/24 via 192.168.1.1

Options

The ifconfig command has a number of options that can be used to modify its behavior. Some of the most common options are:

  • up: Enable the network interface.

  • down: Disable the network interface.

  • netmask: Set the netmask for the network interface.

  • broadcast: Set the broadcast address for the network interface.

  • gateway: Set the default gateway for the network interface.

  • add: Add a route to the routing table.

  • del: Delete a route from the routing table.

For more information on the ifconfig command and its options, please see the man page for ifconfig.

With gencmd

gencmd can help you quickly get the options for the ifconfig

gencmd -c ifconfig change the ip address of a network interface

  • ifconfig <interface> <inet> <address>/<netmask>
  • ifconfig <interface> <inet addr> <netmask>
  • ifconfig <interface> <new_ip_address>