Walking in Light With Christ - hip0's personal blog on System Administration, Free Software, Computer Security and Religion

How to add a range of virtual IPs to a CentOS and Fedora Linux server

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:

IPADDR_START=192.168.1.120
IPADDR_END=192.168.1.250
NETMASK=255.255.255.25
CLONENUM_START=0


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
Cheers ;)