In centos 7 by default ifconfig command will not work.

You need to install it using this command yum install net-tools

1.  Create a file in /opt/1.sh

2.  create ip list in an excel sheet,

Example:

ip addr add		198.xxx.xx.xx		dev enp6s0f0 label		enp6s0f0:1
ip addr add		198.xxx.xx.xx		dev enp6s0f0 label		enp6s0f0:2
ip addr add		198.xxx.xx.xx		dev enp6s0f0 label		enp6s0f0:3
ip addr add		198.xxx.xx.xx		dev enp6s0f0 label		enp6s0f0:4

3. Add ips in /opt/1.sh file

4. Execute sh 1.sh for the ips to display in ifconfig

5. For the ips to reflect in ifconfig even after server is rebooted add this command sh /opt/1.sh in /etc/rc.d/init.d/network file and it should be added above exit $rc