[c-nsp] OSPF summarization

[Oliver Boehmer (oboehmer)]

Michael Malitsky <> wrote on Monday, November 19, 2007 2:04 AM:

> Hello,
> 
> Looking for help with summarizing routes in OSPF.  I have a VPN
>  headend which populates a bunch of host routes into OSPF.  The
> routes are contiguous, so I want to aggregate them.  The headend
> itself lacks such functionality, so I am trying to do this on the
> next OSPF-capable device, which is a PIX v.7.2(2)23.  PIX and VPN
> headend are in area 1, everything else is area 0.  On the PIX the
> host routes show up as "O E2" - OSPF external type 2.  I've tried
> configuring an interarea summary: area 0 range 192.168.3.0
> 255.255.255.0       
> That doesn't seem to do anything at all.  I've also tried an external
>  summary: summary-address 192.168.3.0 255.255.255.0
> Also does nothing.

you can only summarize external routes on the ASBR. Depending on the
topology, you could split the OSPF domain in two and use two different
OSPF processes, redistributing between each other. But I would only
consider this if the pain is too high. How many externals do you inject?


	oli