Internet routing table "completeness" monitoring?

[jra at baylink.com (Jay Ashworth)]

----- Original Message -----
> From: "ML" <ml at kenweb.org>

> Has anyone put in place a method to identify if one their BGP peers
> suddenly withdraws X% of their prefixes?
> 
> e.g I should expect ~420k prefixes in a "complete"[1] routing table from
> a transit peer today. If suddenly I'm only getting 390k prefixes I'd
> guess a major network was depeered or similiar.
> 
> If so how are people doing this? SNMP MIB, screen scrape?

Well, if I had to do it, I think I'd just point munin at the router, yes,
using SNMP, and put the prefix count graph up on the Big Wall, as a filled 
curve.  That thing jumps around, someone will likely notice.

This assumes a staffed NOC, of course, but it still gives you something to
look at historically if you note a problem in an unstaffed situation as well.

Cheers,
-- jra
-- 
Jay R. Ashworth                  Baylink                       jra at baylink.com
Designer                     The Things I Think                       RFC 2100
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