I need to add eth0:1 with a new IP address to my C5-based router.

Does a design document exist for the ifcfg family of scripts that explains how they're to be used? Before I go digging through the script hierarchy I'm hoping someone can point me to documentation to make the process easier.

One confusing issue is that the ifcfg-eth* files in /etc/sysconfig/network-scripts are hard-linked to same-named scripts in sibling directories:

85327883 8 -rw-r--r-- 3 233 Apr 11 12:34 ./networking/devices/ifcfg-eth1 85327884 8 -rw-r--r-- 3 210 Apr 11 12:34 ./networking/devices/ifcfg-eth0 85327883 8 -rw-r--r-- 3 233 Apr 11 12:34 ./networking/profiles/default/ifcfg-eth1 85327884 8 -rw-r--r-- 3 210 Apr 11 12:34 ./networking/profiles/default/ifcfg-eth0 85332182 8 -rw-r--r-- 1 254 Jun 20 2001 ./network-scripts/ifcfg-lo 85327883 8 -rw-r--r-- 3 233 Apr 11 12:34 ./network-scripts/ifcfg-eth1 85327884 8 -rw-r--r-- 3 210 Apr 11 12:34 ./network-scripts/ifcfg-eth0

(I excised the ownerships to make these fit on a line. First column is the inode number.)

I'm not using a GUI, and I figure the easiest way to add an alias is by hand-editing a new config file, but I'd like to know what these hard links are for. Which scripts reference the 3 different paths?