Configure network in CentOS5

$ vi /etc/sysconfig/network-scripts/ifcfg-eth0

for Static

DEVICE=eth0
ONBOOT=yes
HWADDR=00:0c:29:c3:90:85
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes
IPADDR=172.16.1.3
NETMASK=255.255.0.0
GATEWAY=172.16.10.1

for dhcp

DEVICE=eth0
ONBOOT=yes
HWADDR=00:0c:29:c3:90:85
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes
BOOTPROTO=dhcp