Linux IP configuration and Network configuration

Linux ip configuration and Network configuration

Every node participating in networking needs a valid IP address. On Linux command prompt IP address is assigned by a network configuration window. This window can be invoked by selecting network configuration sub menu form setupcommand or directly executing system-config-network commands.

Run setup command form root user

this will launch a new window select network configuration

now a new window will show you all available LAN card select your LAN card ( if you don’t see any LAN card here mean you don’t have install driver)

assign IP in this box and click ok

click on ok, quit and again quit to come back on root prompt.

Alternately you can use system-config-network command directly to invoke this setup window

whatever change you made in network configuration will not take place till you restart the LAN card

ifconfig

The ifconfig command will display the configuration of all active Ethernet card. Without specifying any parameter this command will show all active Ethernet card. if you want to see the configuration of any specific Ethernet card then use the name of that card as the command line arguments. for example to show the IP configuration on loop back Interface execute this command.

ifup/ifdown

Each installed network adapter has a corresponding ifcfg-* file in /etc/sysconfig/network-scripts. You can activate or deactivate that adapter with the ifup and ifdown commands. Either of the following commands will activate the eth0 network adapter: