vi /etc/sysconfig/network
NETWORKING=yes
NETWORKING_IPV6=no
HOSTNAME=elastix.example.com
GATEWAY=111.111.111.111
vi /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
BOOTPROTO=static
HWADDR=00:15:E9:B1:32:AF
IPADDR=222.222.222.222
NETMASK=255.255.255.0
ONBOOT=yes
reboot