Community list regex question

[anthonykahwati]

Hi

Can anyone help me with an expanded community list regex question please?

I couldn't get the below to work. It just picked up nothing, although, on online regex checkers it works:

^(649[0-9][0-9]):(.{1,5})$

I did manage to get the following working though:

649[0-9][0-9]:*

If anyone can let me know where I'm going wrong that would be appreciated.

Many thanks

[Georg Pauwen]

What do you need to match ? In expanded community lists, regular expressions are used to specify patterns to match COMMUNITIES attributes; the syntax you use looks like you are trying to filter on AS.

[anthonykahwati]

Hi

Thanks for replying.

I am trying to match a community list with a name of say 649XX:YYY_CL and it should match any community that starts 649 plus 2 more digits, has a : in the middle and then between 1 and 5 additional characters..

It's definitely trying to match the community value but the AS number of where the traffic came from helps create the actual community value that is assigned to a route.

Thanks

[Seb Rupik]

Hi there,

The second part of your regex (after the colon) does not match enough charecters for your example. It should be:

^(649[0-9][0-9]):(.{1,6})$

...but this can be improved a little:

^649\d{2}:.{1,6}$

cheers,

Seb.

[anthonykahwati]

Hey Seb

Thanks very much. I’ll give it a go. 
out of curiosity, do the Cisco routers support the full range of regex characters and behaviours?

Cheers.