How to add multiple IPs to OVH VPS (Centos system)

The feature of OVH VPS is that each VPS can add 16 IPv4 for free, and the setup of each IP is a one-time 2 euros. Here is how to add multiple IPs.

First enter /etc/sysconfig/network-scripts/, if it is ifcfg-eth0, then do the following:

 vi /etc/sysconfig/network-scripts/ifcfg-eth0:0

Add the following

 DEVICE="eth0:0"
BOOTPROTO=static
IPADDR="1.1.1.1"
NETMASK="255.255.255.255"
BROADCAST="1.1.1.1"
ONBOOT=yes

Change 1.1.1.1 to the extra IP you purchased, and change BROADCAST accordingly (same as the IP).
Restart the network

 ifup eth0:0

If you want to add more IPs, repeat the process.

 vi /etc/sysconfig/network-scripts/ifcfg-eth0:1

Add the following

 DEVICE="eth0:1"
BOOTPROTO=static
IPADDR="1.1.1.2"
NETMASK="255.255.255.255"
BROADCAST="1.1.1.2"
ONBOOT=yes

Change 1.1.1.2 to the extra IP you purchased, and change BROADCAST accordingly (same as the IP).
Restart the network

 ifup eth0:1