ifcfg-ethXを編集
# vi /etc/sysconfig/network-scripts/ifcfg-eth0
// 以下を追記する
IPADDR1=172.16.0.100
NETMASK=255.255.0.0
IPADDR2=172.16.0.101
NETMASK=255.255.0.0
ネットワーク再起動
# service network restart
確認
# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:1b:2b:ce brd ff:ff:ff:ff:ff:ff
inet 172.16.0.100/16 brd 172.16.255.255 scope global eth0
inet 172.16.0.101/16 brd 172.16.255.255 scope global secondary eth0 ←追加された
inet6 fe80::20c:29ff:fe1b:2bce/64 scope link
valid_lft forever preferred_lft forever
参考