""John Neiberger"" wrote in message news:[EMAIL PROTECTED] > > Hello, > > Can any explain what these EXACTLY mean? > > > > ip as-path access-list 1 permit _109_ > > Matches any prefix that passed through AS 109.
the book answer is that the underscore _ matches a lot of things including the beginning and the end of string. so _109_ should in theory match anything with 109 in it, including origination or most recent > > > ip as-path access-list 2 permit _200$ > > Matches any prefix that originated in AS 200. > > > ip as-path access-list 2 permit ^100$ > > Matches any prefix that only has AS 100 in the AS path. This would assume > that AS100 is directly adjacent and the prefix originated there. > > It would probably be helpful for you to learn about BGP regular expressions. > Do a search on Google using the terms "unix regular expressions" and you'll > find plenty of information that should clarify their use. The Cisco world of regulat expressions is found in, of all places, the dial solutions part of the documentation http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/dial _r/drdapp/drdrapre.htm#1017420 watch the wrap. better just to memorize the few most likely _x$ ^x_ _x_ ,* _x_y_ _x_y$ ^x_y_ should serve you pretty well. > > Good luck, > John Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=65997&t=65988 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]