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Re: Regular Expressions ......
I see two problems. 1. _ matches the beginning of the string, the end of the string, space, braces, comma, underscore or parentheses. What you probably wanted in your regexp is a normal space. 2. * matches zero or more of the previous pattern, what you probably wanted was a + (you want to force it to have at least one digit.) Fixing either one of these will produce the results you are looking for. I recommend fixing both. Also, note that you can stack "beginning of string" or "end of string". The following produce the same result. sho ip bgp reg ^_^^[0-9]*^^_^^_^[0-9]*$_$$ sho ip bgp reg ^_^^[0-9]*$___$__[0-9]*$$_$ sho ip bgp reg ^[0-9]*$ the point? Be careful with * and _. pete On Fri, May 26, 2000 at 10:07:50AM +0100, Ally Gudgeon wrote: > > Hi All, > > I am having a few problems getting my BGP filtering to work - and am > experiencing some strange results.. > > I have two routers connected to a peering point, we have decided that we > want to set local preferences of > > 110 to 1-deep AS-paths (as-path ACL 1) > 100 to 2-deep AS-paths (as-path ACL 2) > and 90 to 3-deep AS-paths (as-path ACL 3) > and to not accept 4-deep AS-paths (as-path ACL 4) > > I have the following as-path ACLs to try to set that and am using route > maps. > > ip as-path access-list 1 permit ^[0-9]*$ > ip as-path access-list 2 permit ^[0-9]*_[0-9]*$ > ip as-path access-list 3 permit ^[0-9]*_[0-9]*_[0-9]*$ > ip as-path access-list 4 permit .* > > This appears to have failed miserably....It is not setting local prefs > correctly if they are 3-deep and have a repetition of an AS number it sees > it as 4-deep > If they are 4 AS's deep it doesn't apply a local preference but if it knows > it from our other core router it sets a local pref of 100 but prefers the > direct route? > > (ALSO: If I do a sh ip bgp reg ^[0-9]*_[0-9]*$ it lists both 1-deep and > 2-deep AS's....surely it should just list 2-deep?) > > Any help would be greatly appreciated!...... > > Thanks in advance.. > > > Ally > > > email - [email protected] > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > This email and any files transmitted with it are confidential and intended > solely for the use of the individual or entity to whom they are addressed. > The views expressed in the email and files transmitted with it are those of > the individual, not the company. If you have received this email in error > please notify [email protected] > +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > > >