Configure The Network Card In Redhat 5.3 Advanced Server

Somtimes you need to configure or reconfigure your network settings. What options are available for doing that? In Redhat (applies to Fedora & Centos too), there are 3 different methods for configuring the network settings:

[1] The command line text based GUI tool (No X Windows required) – system-config-network

[2] You can edit the configuration files stored in /etc/sysconfig/network-scripts/ directory.

[3] Use The GUI tool (X Windows required) – system-config-network

Let’s look at each of the options.

Command Line Based GUI Tool

From a terminal window, type:  system-config-network and press return. You should see the following displayed:

From there you can change your device settings.

Edit The Network Configuration Files Directly

From a terminal window type:

cd /etc/sysconfig/networking-scripts

You will need to edit the following filess:

/etc/sysconfig/network-scripts/ifcfg-eth0  (and eth1 if you have another card.)
/etc/sysconfig/network-scripts/ifcfg-eth0

Change or Add New Info

cd /etc/sysconfig/network-scripts/

vi ifcfg-eth0

Change or Add The Following Lines

# Xen Virtual Ethernet
DEVICE=eth0
BOOTPROTO=none
BROADCAST=10.10.1.255
HWADDR=56:36:DC:8F:D5:59
IPADDR=10.10.1.73
NETMASK=255.255.255.0
NETWORK=10.10.1.0
ONBOOT=yes
GATEWAY=10.10.1.1
TYPE=Ethernet
Setup A Default Gateway
vi /etc/sysconfig/network

NETWORKING=yes
NETWORKING_IPV6=no
HOSTNAME=myhostname
GATEWAY=10.10.1.1

Make sure your DNS entries are correct. Set them to the correct values, whatever those are. For example:
vi /etc/resolv.conf

nameserver 10.10.1.13
nameserver 10.10.1.14
search mydomain.com
Save the file & restart the network service:
service network restart
The GUI Tool
You can also launch the system-config-network tool in GUI mode. From a command line where you are running X-Windows, type system-config-network, or chose System / Administration / Network from the menu. You should see:

Configure your network settings here.