Troubleshooting guide

Troubleshooting

#show ip bgp neighbors 10.15.43.34 advertised-routes

BGP local router ID is 10.0.0.1, local AS is 101.

Status codes: * valid, > best, i - internal

Origin codes: i - IGP, e - EGP, ? - incomplete

Network NextHop Metric Path

*> 1.0.0.0/8 10.15.43.17 1 100 i

*> 2.0.0.0/9 10.15.43.17 1 100 i

Show IP BGP Regexp

Use the show ip bgp regexp command to display a summary of the BGP route table that includes routes

whose AS path matches the specified expression.

#show ip bgp regexp <expression>

<expression> Specifies the regular expression to match when displaying BGP routes. Only those routes

whose AS path matches this expression will be displayed in the output.

The following sample output of the show ip bgp regexp_303_ command shows all of the entries in the

BGP database that contain 303 in the AS path.

#show ip bgp regexp _303_

BGP local router ID is 192.168.3.1, local AS is 304.

Status codes: * valid, > best, i - internal, o - local

Origin codes: i - IGP, e - EGP, ? - incomplete

Network NextHop Metric LocPrf Path

10.22.130.8/29 10.22.132.9 303 304 302 i

* i10.22.130.240/28 10.22.132.1 100 303 300 i

* 10.22.130.240/28 10.22.132.9 303 300 i

10.22.131.0/29 10.22.132.9 303 304 302 i

10.22.131.8/29 10.22.132.9 303 304 302 i

* i10.22.131.16/29 10.22.132.1 0 100 303 i

* 10.22.131.16/29 10.22.132.9 0 303 i

* i10.22.131.240/28 10.22.132.1 100 303 300 i

* 10.22.131.240/28 10.22.132.9 303 300 i

* 10.22.132.0/29 10.22.131.1 0 302 303 i

* 10.22.132.0/29 10.22.131.9 0 302 303 i

* i10.22.132.0/29 10.22.132.1 0 100 303 i

*> 10.22.132.0/29 10.22.132.9 0 303 i

* 10.22.132.8/29 10.22.131.1 0 302 303 i

* 10.22.132.8/29 10.22.131.9 0 302 303 i

Regular expressions are strings of characters used in BGP to identify routes by their AS

path. Refer to AS Regular Expressions on page 83 for a detailed list of valid AS regular

expressions.

Entries that are not filtered by a local BGP policy are marked with an asterisk (*) to show

they are valid. Entries that are deemed the best path to an advertised route are marked with

a caret (>).