BGP regexp syntax help

From: Joshua W. Watkins (josh@xxxxxxxxxxx)
Date: Wed Jun 14 2000 - 03:33:59 GMT-3


   

When using the following config for an as-path filter to filter all
routes originating from AS600 to remote AS 500, BGP ends up denying
everyting.

router bgp 100
 no synchronization
 bgp confederation identifier 666
 neighbor 172.16.4.5 remote-as 500
 neighbor 172.16.4.5 filter-list 1 out
 neighbor 172.16.10.1 remote-as 100
 neighbor 172.16.10.1 next-hop-self
!
ip classless
ip as-path access-list 1 deny ^600$
ip as-path access-list 1 permit .*

I then change the ip as-path access-list to deny _600$ instead of deny
^600$ and BGP filters all routes originating from AS 600 and allows
everything else. Can someone explain why _600$ works and ^600$ does
not?

Thanks.

Joshua W. Watkins
Systems Engineer
Mountain States Networking



This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 08:23:41 GMT-3