Max Prefixes Configured on Customer BGP

Niels Bakker niels=nanog at bakker.net
Fri Aug 16 01:30:24 UTC 2002


* ras at e-gerbil.net (Richard A Steenbergen) [Fri 16 Aug 2002, 03:01 CEST]:
[..]
> IMHO AS Path filters are useless and redundant if you have proper
> prefix-lists.

Did you ever run into that bug in IOS where if you had `ip as-path
access-list 1 permit ^(1|2|3)+_$' (where 2 and 3 would be customers of
AS1 who is one of your peers), and the third number is higher than the
second number?  IOS seemed to optimise that case out and reject AS paths
of ^1_2$ if the filter was written as ^(1|3|2)+_$.

This was several years ago though.


	-- Niels.



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