Recently I had the task to add a range of few IP addresses to as a virtual interface IPs.
The normal way to do that is of course using the all well known ifconfig eth0:0, ifconfig eth0:1 or using a tiny shell script which does it and set it up to run through /etc/rc.local .
However the Redhat guys could omit all this mambo jambo and do it The Redhat way TM 😉 by using a standard method documented in CentOS and RHEL documentation.
Here is how:
# go to network-script directory[root@centos ~]# cd /etc/sysconfig/network-scripts
# create ifcfg-eth0-range (if virtual ips are to be assigned on eth0 lan interface[root@centos network-scripts]# touch ifcfg-eth0-range
Now inside ifcfg-eth0-range, open up with a text editor or use the echo command to put inside:
Now save the /etc/sysconfig/network-scripts/ifcfg-eth0-range file and finally restart centos networking via the network script:
[root@centos network-scripts]# service network restart
That’s all now after the network gets reinitialized all the IPs starting with 192.168.1.120 and ending in 192.168.1.250< will get assigned as virtual IPs for eth0 interface