How to Configure Static IP Address on CentOS 6.2

After you have installed CentOS 6.2 linux server, the network configuration will be like this.

DEVICE="eth0"
HWADDR="xx:xx:xx:xx:xx:xx"
NM_CONTROLLED="yes"
ONBOOT="no"

The system will no get the ip automatically and the network interface will not auto start even after the server rebooted. Follow this steps to set static ip and set it auto start once rebooted in CentOS 6.2 :
1. Configure eth0:

[root@centos6 ~]# vi /etc/sysconfig/network-scripts/ifcfg-eth0

DEVICE="eth0"
HWADDR="00:0C:29:67:51:B1"
NM_CONTROLLED="yes"
ONBOOT="yes"
IPADDR=192.168.1.44
BOOTPRO=static
NETMASK=255.255.255.0

2. Configure Default gateway:

[root@centos6 ~]# vi /etc/sysconfig/network

NETWORKING=yes
HOSTNAME=centos6.2
GATEWAY=192.168.1.1

3. Restart Network interface:

[root@centos6 ~]# /etc/init.d/network restart

or

[root@centos6 ~]# Service network restart

4. Configure DNS server:

[root@centos6 ~]# vi /etc/resolv.conf

nameserver 8.8.8.8
nameserver 192.168.1.1