From: Scott Morris (swm@emanon.com)
Date: Thu Feb 15 2007 - 15:50:56 ART
Since ^ means beginning of line, your first one would be things not only
originating in AS54, but learned by you directly FROM AS 54.
With the _ that is possible as well, but it also allowed for other AS
numbers in between the originating point and your own AS.
HTH,
Scott Morris, CCIE4 (R&S/ISP-Dial/Security/Service Provider) #4713, JNCIE
#153, CISSP, et al.
CCSI/JNCI-M/JNCI-J
IPexpert VP - Curriculum Development
IPexpert Sr. Technical Instructor
smorris@ipexpert.com
http://www.ipexpert.com
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Curt
Gregg (cugregg)
Sent: Thursday, February 15, 2007 1:08 PM
To: Cisco certification
Subject: Question: BGP REG ^54$ or _54$
Question:
Wouldn't these two expressions be the same or you trying to match anything
originating in AS 54?
ip as-path access-list 1 permit ^54$
^ = start of a line
or
ip as-path access-list 1 permit _54$
_ = beginning of the line (or end of the line or a space)
Wouldn't _54$ also be considered the end of the path or originating AS as
the as-path describes the AS systems it has passed thru beginning with the
most recent and ending with the originating AS.
In this case AS 54 is the directly connected AS.
Are there pros or cons to using either or?
TIA
Curt
This archive was generated by hypermail 2.1.4 : Thu Mar 01 2007 - 07:38:46 ART