iSCSI IP Address Fun

Problem

A user accidentally assigned the default gateway as the IP address to a computer. Hilarity ensued.

When we tried to reconfigure the computer to be a different address, the computer behaved as if it had IP addresses assigned both on the different address, and the original address.

Solution

This computer was installed on an iSCSI LUN.

The reason that the default gateway address did not go away is because when Red Hat installs to an iSCSI drive and it is given a static IP address it writes it (and other things) into the initrd file (which makes sense, because otherwise it won't find its drive at boot time). So no matter what you do to the network config files that (initrd-supplied) address will be an active IP address on the server.

Fix the initrd (left as an exercise for the reader).