I'm not sure if you already have your answers, but:
> It would seem that I could just inject a route statement into IGRP saying
> "yes, I'm always responsible for the following aggregate routes (the four
> /24's we've been allocated)" but I'm not quite sure how to do it. Anytime
> I remove (what I call a "hold-down" IP) from the loopback interface, the
> route for that entire /24 dies at the upstream (it works fine internally).
Yes, you want to setup static routes on your border router for your
networks, and then do a redistribute static into IGRP. This will tie
your routes down, and prevent you from accidentally failing to
advertise your nets.
> I am redistributing my OSPF process into (their) IGRP, and I have network
> commands for each of my /24's in the OSPF process. It all works fine
> internally.
Argh! Having been there and done that, I can heartily recommend that
one not do this. OSPF redistribution into IGRP is poor. IGRP being
classless, can fail in a number of horrible ways to correctly
advertise routes learned from OSPF.
> > With only a single provider, running -any- IGP with your provider could be
> > very unwise. Static routes are preferred.
> > Even with the best of access lists, eventually someone will forget to
> > maintain the lists and you could end up trashing each other's IGP's and
> > perhaps networks. I've seen it happen a lot of times. Any instability on
> > either end impacts the other in the form of more wasted WAN bandwidth and
> > increased CPU to process the route flaps.
> > Redistribution also gets messy from one IGP to another.
Agree. There's no reason to run an IGP with your provider when
singly-homed, unless you are frequently adding prefixes, and they
don't choose to filter you (bad, bad ISP).
If you must do so, definitely filter your routes learned from them,
and try to avoid IGP redistribution as a method for generating
advertisements.
---- Kirby Files Network Engineer GTE Internetworking kfiles@bbnplanet.com
This archive was generated by hypermail 2b29 : Sun Aug 04 2002 - 04:13:14 EDT