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Dear all,
I want to ask about regulat expression, * and [], () From my understanding, show ip bgp regxp 1234(_[0-9]*)$ will show all bgp route with as path starting from 1234 and zero or one other as in the as path (eg., 1234 4321, or 1234) But if without $, the result is all bgp routes with as path starting from 1234 and 0 or MORE other as in the as path (eg., 1234, 1234 4321, 1234 4321 4567 122) why??
$ means the end of the pattern, but which symbol mean the repeat pattern??? The * is inside (), next to [0-9]. The repeat pattern should apply on character 0-9 only. Inside the (), there is a _ also, which can be “space” or end of string. Why without the $, the show ip bgp rexp 1234(_[0-9]*) can be something like:
R1#sh ip bgp regexp 1234(_[0-9]*) BGP table version is 3, local router ID is 10.155.129.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale Origin codes: i - IGP, e - EGP, ? - incomplete Network Next Hop Metric LocPrf Weight Path *> 3.0.0.0 10.155.129.2 200 0 1234 103 80 i *> 8.5.250.0/24 10.155.129.4 200 0 1234 10 13 15 i *> 15.149.2.0/24 10.155.129.4 200 0 1234 10 i
Regards, Howard Yahoo! g62d8 e. e(f;g%o http://hk.promo.yahoo.com/security/index.htmld:h’#f4e$!