Monitoring BGP Community Routes in the Community List

Purpose

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

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

Action

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

host1#show ip bgp community-list 1 fields peer communities

Local router ID 192.168.1.153, local AS 100
  72077 paths, 72077 distinct prefixes (5189544 bytes used)
  72077 paths selected for route table installation
  21627 path attribute entries (2957324 bytes used)

Prefix             Peer            Communities
3.0.0.0/8          10.5.0.48       777:777 888:888
4.0.0.0/8          10.5.0.48       777:777 888:888
4.17.106.0/24      10.5.0.48       777:777 888:888
4.17.115.0/24      10.5.0.48       777:777 888:888
6.0.0.0/8          10.5.0.48       777:777 888:888
9.2.0.0/16         10.5.0.48       777:777 888:888
9.20.0.0/17        10.5.0.48       777:777 888:888
12.0.0.0/8         10.5.0.48       777:777 888:888

Meaning

Table 30 lists the show ip bgp community-list command output fields.

Table 30: show ip bgp community-list 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.

paths 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

Communities

Community number in AA:NN format:

  • AA—Number that identifies the autonomous system
  • NN—Number that identifies the community within the autonomous system

Related Documentation