Here's another thought. I did something like it last week. I can't try it right now because my routers are busy with another lab and I don't want to tinker with them.
Let's say you have four routers: A---(IGRP /28)----B----(OSPF /24)-----C----(OSPF)-----D Create a tunnel between A and B and give it an address with a /24 mask. On B, place the tunnel into the IGRP process and redistribute from OSPF to IGRP. Make sure to advertise the tunnel network into OSPF. When you're done, A should be able to ping D. I think. :-) I did the reverse last week, where A-B was a /24 and B-C was a /28. It worked great so I'd assume this ought to work as well, but there may be some gotchas that I haven't thought about. If I finish this lab up tonight I'll give this scenario a try. Regards, John ________________________________________________ Get your own "800" number Voicemail, fax, email, and a lot more http://www.ureach.com/reg/tag ---- On Wed, 12 Dec 2001, Chuck Larrieu ([EMAIL PROTECTED]) wrote: > (REPOST) > > I've been fighting with one of my practice labs the last couple of days. > The > problem is one of those OSPF to IGRP redistribution with a twist. The > IGRP > domain is /28. So how to get those shorter /24 prefixes advertised. Oh > yeah, > you can't use the default-network command to create an IGRP default > route. > > So let me offer this possibility. > > IP local policy route-map > > the route map then goes something like this: > > route-map igrp-default permit 10 > set default interface [whatever the interface is] > > I also suspect that set ip default next-hop x.x.x.x works also, but at > the > time I was testing I hadn't thought through all the implications, and my > test failed. > > In any case, the local policy would have to be implemented on all > routers in > the IGRP domain. A bit of planning, then, is required. > > I found out something else that was interesting. Local policy packets > seem > to have a particular way they are constructed. the first time I looked > at my > debug ip packet, the source address was one of my loopback addresses, > which > I was not advertising under IGRP. So of course my pings failed, because > the > distant end did not have a route back. So I deleted the loopback, tried > again, and this time the source address was a LAN interface, this too > not > advertised under IGRP. I am assuming that Cisco has a hierarchy of > interfaces. Usually a ping is sourced at the interface out which the > packets > are headed. But for local policy, it was different. > > Any case, I am offering these observations for consideration. > > Wish I hadn't turned my routers off last night. Or I could gather some > screen shots. > > Chuck [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=29027&t=29027 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
