You are correct. The ^ character symbolizes the beginning of the AS path so you're as-path access list looks like it should work exactly as you think. I'm not aware of the ^ having any other meaning in this context. I used to have a link on regular expressions but I can't seem to find it. If I come across it I'll post it to the list.
John >>> "Chuck Larrieu" 10/28/01 10:00:53 PM >>> for an as-path filter, here is what I want to accomplish: from one particular router to another particular router I want to filter any AS path whose most recent AS was 5555 so if the BGP route has a path in the BGP table as 5555 1111 4444 ? or 5555 9999 ? etc then I want that route to be filtered to a particular neighbor routes such as 3333 5555 ? or 7777 2222 5555 3333, for example are OK to pass my access-list is: ip as-path access-list 55 deny ^5555_ ip as-path access-list 55 permit .* ! and my neighbor statement is neighbor a.b.c.d filter-list 55 out does the ^ character really mean what I think it is supposed to mean? I.e does it filter any AS path that BEGINS with 5555, or is it doing something unexpected? I have a complex mesh ( mess too ;-> ) of BGP neighbors, and it is a bit hard to tell if I am accomplishing what I think I am accomplishing. thanks. Chuck Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=24528&t=24460 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]