BGP Regular Expressions Examples

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9

Hi Nitay,

Sometimes, there are multiple ways to achieve the same thing with regex. The _ matches the space in between the AS numbers.

If this is what you want, I would use this regex:

show ip bgp regex ^([0-9]+)51$

The $ matches the end of the string. Here’s a quick test on a looking glass server for AS 4826:

route-views.optus.net.au>show ip bgp regex ^([0-9]+)_4826$
BGP table version is 1021954775, local router ID is 203.202.125.6
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale, m multipath, b backup-path, x best-external
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*  43.241.188.0/22  202.139.124.130         10             0 7474 4826 i
*                   203.13.132.7             1             0 7474 4826 i
*                   203.202.143.34                         0 7474 4826 i
*>                  203.202.143.33                         0 7474 4826 i
*                   192.65.89.161            1             0 7474 4826 i

It only shows results for AS 4826 behind any of our directly connected ASes. It won’t match on any ASes behind AS 4826.

Is this what you were looking for?

Rene

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