Manipulating The Community Attribute - Dell S3048-ON Configuration Manual

Manipulating the COMMUNITY Attribute

In addition to permitting or denying routes based on the values of the COMMUNITY attributes, you can manipulate the COMMUNITY
attribute value and send the COMMUNITY attribute with the route information.
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 group specified.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} send-community
To view the BGP configuration, use the show config command in CONFIGURATION ROUTER BGP mode.
If you want to remove or add a specific COMMUNITY number from a BGP path, you must create a route map with one or both of the
following statements in the route map. Then apply that route map to a BGP neighbor or peer group.
1 Enter ROUTE-MAP mode and assign a name to a route map.
CONFIGURATION mode
route-map map-name [permit | deny] [sequence-number]
2 Configure a set filter to delete all COMMUNITY numbers in the IP community list.
CONFIG-ROUTE-MAP mode
set comm-list community-list-name delete
OR
set community {community-number | local-as | no-advertise | no-export | none}
Configure a community list by denying or permitting specific community numbers or types of community.
• community-number: use AA:NN format where AA is the AS number (2 or 4 Bytes) and NN is a value specific to that
autonomous system.
• local-AS: routes with the COMMUNITY attribute of NO_EXPORT_SUBCONFED and are not sent to EBGP peers.
• no-advertise: routes with the COMMUNITY attribute of NO_ADVERTISE and are not advertised.
• no-export: routes with the COMMUNITY attribute of NO_EXPORT.
• none: remove the COMMUNITY attribute.
• additive: add the communities to already existing communities.
3 Return to CONFIGURATION mode.
CONFIG-ROUTE-MAP mode
exit
4 Enter the ROUTER BGP mode.
CONFIGURATION mode
router bgp as-number
5 Apply the route map to the neighbor or peer group's incoming or outgoing routes.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} route-map map-name {in | out}
202 Border Gateway Protocol IPv4 (BGPv4)