From: Foster, Kristopher (KFoster@xxxxxxxxxxxxxxxxxxxx)
Date: Tue Oct 17 2000 - 17:00:06 GMT-3
Jack,
Really wish I had my copy of Halabi with me. Somewhere in there he has a
really excellent diagram detailing the order in which filters/route-maps/etc
are applied. Basically, yes you can do this, but like in math, watch your
order of operations. Flip around in there, you'll find it :)
Kris,
-----Original Message-----
From: Jack Heney [mailto:jheneyccie@hotmail.com]
Sent: Tuesday, October 17, 2000 3:17 PM
To: ccielab@groupstudy.com
Subject: BGP filtering
Halabi, pg. 317:
Router bgp 1
neighbor INTERNALMAP peer-group
neighbor INTERNALMAP remote-as 1
neighbor INTERNALMAP route-map INTERNAL out
neighbor INTERNALMAP filter-list 1 out
neighbor INTERNALMAP filter-list 2 in
neighbor 172.16.11.1 peer-group INTERNALMAP
neighbor 172.16.13.1 peer-group INTERNALMAP
My question is this...I had always assumed that you couldn't use both an
outbound filter and an outbound route-map to the same neighbor...I based
that assumption on the fact that the route-map itself could act as a
filter...According to Halabi, however, this is an acceptable configuration,
so which logic is processed first? What if I incorporate an AS-path filter
in an outbound route-map that explicitly permits traffic that was explicitly
denied by the AS-path list referenced in the filter-list command?
Thanks in advance for any help,
Jack
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 08:25:27 GMT-3