1. Determine what existing range files exist: # cd /etc/sysconfig/network-scripts/ # ls ifcfg-eth1-range* You will see at least one file, possibly several. Find the highest number following the “range” and add one to it. This will be the new range number. For example, if you see ifcfg-eth1-range0 and ifcfg-eth1-range1, your new range number will be ..