nanog mailing list archives
Re: As-Path filtering based on ranges, not regex
From: Brett Frankenberger <rbf () rbfnet com>
Date: Fri, 17 Jan 2003 11:53:02 -0600
On Fri, Jan 17, 2003 at 12:10:59PM -0500, Andy Johnson wrote:
Vincent, I'm fairly certain it can match a range, just as you yourself posted you could do. There is no difference between using a range to find 0-9, than there is finding 64512-65535.
There is in regular expressions.
So your line would look something like this: ip as-path access-list 150 permit _[64512-65535]$
[0123] is a one-character regular expression matching the digit 0, 1, 2, or 3. [3-5] is a one-character regular expression matching 3, 4, or 5. [64512-65535] is a one-character regular expression matching 1,2,3,4,5 or 6. (It's way more complex than it needs to be, of course. You've got 6 listed in there twice; five is listed 4 times and also included in the 2-6 range, and so on.) So your expression above is going to match paths ending with AS 1, 2, 3, 4, 5, or 6. -- Brett
Current thread:
- As-Path filtering based on ranges, not regex Vincent Gillet (Jan 17)
- Re: As-Path filtering based on ranges, not regex Andy Johnson (Jan 17)
- Re: As-Path filtering based on ranges, not regex Brett Frankenberger (Jan 17)
- Re: As-Path filtering based on ranges, not regex Andy Johnson (Jan 17)