edit /etc/sysconfig/network-scripts/ifcfg-eth0
it will looks like
TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=none
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=eth0
UUID=cb90e0ae-2f94-41af-9d9b-ce6b8e5a3f93
DEVICE=eth0
ONBOOT=yes
IPADDR=192.168.16.46
PREFIX=20
GATEWAY=192.168.16.1
DNS1=192.168.16.9
IPV6_PRIVACY=no