Define a BGP4+ Extended Community

You must define a BGP4 extended community filter before you can apply the filter.

Procedure

  1. Access global configuration mode.
    device# configure terminal
  2. Specify an extended community list instance.
    device(config)# ip extcommunity-list standard mylist permit soo 123:2
    This example specifies the extended community list titled mylist and allows site of origin (SOO) from network 2 in autonomous system 123.
    Note

    Note

    The ip-extcommunity-list command supports a range of extended instances from 100 through 500, beyond the standard range of 1 through 99.
  3. Create an inbound route map instance and enter route-map configuration mode.
    device(config)# route-map extComRmap permit 10
    This example creates the extComRmap route map that allows a matching pattern, with an instance ID of 10.
  4. Configure the route map to match the extended community list.
    device(config-route-map-extComRmap/permit/10)# match extcommunity mylist
  5. Exit route-map configuration mode.
    device(config-route-map-extComRmap/permit/10)# exit
  6. Create an outbound route map instance and enter route-map configuration mode.
    device(config)# route-map sendExtComRmap permit 10
    This example creates the sendExtComRmap route map that allows a matching pattern, with an instance ID of 10.
  7. Specify the route target (RT) extended community attribute.
    device(config-route-map-sendExtComRmap/permit/10)# set extcommunity rt 3:3
    This example specifies the set extcommunity command, the rt keyword, and the extcommunityvalue variable.
  8. Set the extended community attribute in the route-map instance.
    device(config-route-map-sendExtComRmap/permit/10)# set extcommunity soo 2:2
    This example specifies the SOO extended community attribute with the soo keyword and the extcommunityvalue variable.

Example

The following example summarizes the commands in this procedure.

device# configure terminal
device(config)# ip extcommunity-list standard mylist permit soo 123:2
device(config)# route-map extComRmap permit 10
device(config-route-map-extComRmap/permit/10)# match extcommunity mylist
device(config-route-map-extComRmap/permit/10)# exit
device(config)# route-map sendExtComRmap permit 10
device(config-route-map-sendExtComRmap/permit/10)# set extcommunity rt 3:3
device(config-route-map-sendExtComRmap/permit/10)# set extcommunity soo 2:2