[c-nsp] IOS XR BGP

Mark Tinka mtinka at globaltransit.net
Mon Nov 28 09:39:27 EST 2011


On Friday, November 25, 2011 12:04:04 AM Oliver Boehmer 
(oboehmer) wrote:

> But have you thought about orignating the aggregates you
> advertise to the Internet (and customers) via some
> central routers in your core, for example some RRs,
> instead of on the edge(s)? This way you will never
> advertise them in case your edge devices become isolated
> (which, if I read you correctly, is the purpose of this
> exercise?).
> 
> If you chose this approach, you might also want to
> advertise these aggregates with a special next-hop (like
> a private 10.1.1.1), and add a static null0 to
> 10.1.1.1/32 on all your BGP routers. Then every router
> seeing the aggregate will automatically create a Null0
> and will drop all packets to unallocated address space
> within these aggregates as soon as it enters your
> network?

Exactly what we do - routes are originated from our route 
reflectors, announced into the network with a next-hop of 
'192.0.2.1' and '2001:db8::1'. 

Never had to worry about dead peering routers causing 
blackholes.

Cheers,

Mark.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 836 bytes
Desc: This is a digitally signed message part.
URL: <https://puck.nether.net/pipermail/cisco-nsp/attachments/20111128/898222cd/attachment.sig>


More information about the cisco-nsp mailing list