Monitoring BGP Routes in a Community

Purpose

Display all routes that are members of the specified BGP community. Report whether the indirect next hop of a route is unreachable; if not, display the IGP cost to the indirect next hop. Does not accept regular expressions.

The show ip bgp community and show bgp ipv6 community commands display similar information.

Action

To display all routes that are members of the specified BGP community:

Note:

Specify the community number in AA:NN format:

  • AA—Number that identifies the autonomous system
  • NN—Number that identifies the community within the autonomous system
host1#show ip bgp community 999:999

Local router ID 192.168.1.153, local AS 100
  40845 paths, 40845 distinct prefixes (2940840 bytes used)
  40845 paths selected for route table installation
  13651 path attribute entries (1864908 bytes used)

  Prefix        Peer       Next-hop        MED CalPrf Weight Origin
> 24.0.0.0/12   10.5.0.48  10.5.0.48            100    100    IGP
> 24.4.252.0/22 10.5.0.48  10.5.0.48            100    100    IGP
> 24.6.0.0/23   10.5.0.48  10.5.0.48            100    100    IGP
> 24.6.11.0/24  10.5.0.48  10.5.0.48            100    100    IGP

Meaning

Table 29 lists the show ip bgp community command output fields.

Table 29: show ip bgp community Output Fields

Field Name

Field Description

Local router ID

BGP router ID of the local router

local AS

Local autonomous system number

routes

Total number of routes stored in the BGP routing table and amount of memory consumed by routes. If several peers have advertised a route to the same prefix, all routes are included in this count.

paths

Total number of routes stored in the BGP routing table. If several peers have advertised a route to the same prefix, all routes are included in this count.

distinct prefixes

Number of routes to unique prefixes stored in the BGP routing table. If several peers have advertised a route to the same prefix, only the best route is included in this count.

routes selected for route table installation

Number of routes in the BGP routing table that have been inserted into the IP routing table

path attribute entries

Number of distinct path attributes stored in BGP's internal path attributes table. If BGP receives two routes for different prefixes but with identical path attributes, BGP will create only one entry in its internal path attribute table and share it between the two routes to conserve memory.

Prefix

Prefix for the routing table entry

Peer

IP address of BGP peer

Next hop IP address

IP address of the next hop

MED

Multiexit discriminator for the route

CalPrf

Calculated preference for the route

Weight

Assigned path weight

Origin

Origin of the route

Related Documentation