Filtering Routes with Community ListsTo use an IP community list or IP extended community list to filter routes, you must apply a matchcommunity 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 moderoute-map map-name [permit | deny] [sequence-number]2. Configure a match filter for all routes meeting the criteria in the IP community or IP extendedcommunity list.CONFIG-ROUTE-MAP modematch {community community-list-name [exact] | extcommunity extcommunity-list-name [exact]}3. Return to CONFIGURATION mode.CONFIG-ROUTE-MAP modeexit4. Enter ROUTER BGP mode.CONFIGURATION moderouter bgp as-numberAS-number: 0 to 65535 (2-Byte) or 1 to 4294967295 (4-Byte) or 0.1 to 65535.65535 (Dotted format)5. Apply the route map to the neighbor or peer group’s incoming or outgoing routes.CONFIG-ROUTER-BGP modeneighbor {ip-address | peer-group-name} route-map map-name {in | out}To view the BGP configuration, use the show config command in CONFIGURATION ROUTER BGPmode. To view a route map configuration, use the show route-map command in EXEC Privilege mode.To view which BGP routes meet an IP community or IP extended community list’s criteria, use the showip bgp {community-list | extcommunity-list} command in EXEC Privilege mode.Manipulating the COMMUNITY AttributeIn addition to permitting or denying routes based on the values of the COMMUNITY attributes, you canmanipulate the COMMUNITY attribute value and send the COMMUNITY attribute with the routeinformation.By default, Dell Networking OS does not send the COMMUNITY attribute.To send the COMMUNITY attribute to BGP neighbors, use the following command.• Enable the software to send the router’s COMMUNITY attribute to the BGP neighbor or peer groupspecified.CONFIG-ROUTER-BGP modeneighbor {ip-address | peer-group-name} send-communityBorder Gateway Protocol IPv4 (BGPv4) 205
