Administrator Guide

Configuring an IP Extended Community List
To configure an IP extended community list, use these commands.
1. Create a extended community list and enter the EXTCOMMUNITY-LIST mode.
CONFIGURATION mode
ip extcommunity-list extcommunity-list-name
2. Two types of extended communities are supported.
CONFIG-COMMUNITY-LIST mode
{permit | deny} {{rt | soo} {ASN:NN | IPADDR:N} | regex REGEX-LINE}
Filter routes based on the type of extended communities they carry using one of the following keywords:
● rt: route target.
● soo: route origin or site-of-origin. Support for matching extended communities against regular expression is also
supported. Match against a regular expression using the following keyword.
● regexp: regular expression.
To set or modify an extended community attribute, use the set extcommunity {rt | soo} {ASN:NN | IPADDR:NN}
command.
To view the configuration, use the show config command in CONFIGURATION COMMUNITY-LIST or CONFIGURATION
EXTCOMMUNITY LIST mode or the show ip {community-lists | extcommunity-list} command in EXEC Privilege
mode.
Dell#show ip community-lists
ip community-list standard 1
deny 701:20
deny 702:20
deny 703:20
deny 704:20
deny 705:20
deny 14551:20
deny 701:112
deny 702:112
deny 703:112
deny 704:112
deny 705:112
deny 14551:112
deny 701:667
deny 702:667
deny 703:667
deny 704:666
deny 705:666
deny 14551:666
Dell#
Filtering Routes with Community Lists
To use an IP community list or IP extended community list to filter routes, you must apply a match community filter to a route
map and then apply that route map to a BGP neighbor or peer group.
1. Enter the ROUTE-MAP mode and assign a name to a route map.
CONFIGURATION mode
route-map map-name [permit | deny] [sequence-number]
2. Configure a match filter for all routes meeting the criteria in the IP community or IP extended community list.
CONFIG-ROUTE-MAP mode
match {community community-list-name [exact] | extcommunity extcommunity-list-name
[exact]}
3. Return to CONFIGURATION mode.
CONFIG-ROUTE-MAP mode
Border Gateway Protocol IPv4 (BGPv4)
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