Ah. So this was the automation Sean was referring to - not accepting more specifics of routes with identical AS paths.
telehouse1#conf t Enter configuration commands, one per line. End with CNTL/Z. telehouse1(config)#router bgp 5413 telehouse1(config-router)# neighbor x.x.x.x filter-list 199 in summary-only
... Pipedream? I think it would actually be implementatable. I see Paul F has managed to get himself on the CC list :-)
Alex Bligh Xara Networks
I thought of building configs to do that (assuming a filter-list xx in summ) but it's difficult to tell which sets of contiguous BGP announcements are being announced un-aggregated in an attempt to direct traffic one way or another... Without trying to start any religious fights, I would point out that a database of what things 'should' look like would be one way to store such information (about desired/required specificity). I'll update it this week, but look at http://routes.netaxs.com for a route-aggregation-suggestion tool that I built last year to see "how bad" the problem was - or, more specifically, how much space could be saved by taking compressing contiguous routes with the same next-hop (or head of the AS-Path list, pick which you prefer - they're 95% the same) at an exchange point. The page currently has data from April. Stuff in
= 207/8 is particularly ugly.
Avi