North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical RE: Cisco Route filtering [was Re: OPS: BGP spew from ASN 7374]
> I've had a question on this for some time that maybe can get answered > here. > > Let's assume for a moment that I have a network of 209.123/18 > (1/4 of a > classful B). > > Let's further assume that my upstream filters me with: > > access-list 2002 permit ip host 209.123.0.0 host 255.255.0.0 > neigh 2.3.4.5 distrib 2002 in > > Will my /18 announcement make it through this /16 filter? No. The ACL specifies an exact match. > Would the same be true with a prefix-length filter, which I assume the > syntax would be: > > ip prefix-list 1 permit 209.123.0.0/16 > neigh 2.3.4.5 prefix-list 1 in > Same deal. Chris
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