I've seen a specialty provider renumber about 15 class C's _twice_, the
first because he changed providers and they urged him to CIDRize. He then
had to change again when the first provider didn't live up to the contractual
obligations. Because of a lack of planning on his part, he lost 20% of
his customer space during/after these renumberings--customers don't want to
put up with problems such as a) applications which compute the IP address
into an equation with the license number, b) problems with _all_ parameters
not being changed in terminal servers and hosts, c) DNS problems with
off-site backup servers, and a few others that just generally made his
customers not happy.
(Keep in mind that "a)" above generally requires you to purchase new
licenses from the software manufacturer.)
The problem, you ask? I don't see very many resources available which
help ISP's to renumber more easily--time line planners, reminder lists
with commonly-missed parameters, etc.
We could use your help in the PIER wg. The areas you have identified
are areas that need a lot of work. (Note that I have renumber large
chunks of space three times, 127 class C nets, a class B and part of
a class A)
If you could help identify those vendors who make use of a), then
we could take soem time to wrok with them on other methods.
b) is being worked on by Dave O'Leary and c) is part of the Dynamic