BGP accept-own Community

Benefits of BGP accept-own Community Attribute

• Helps to leak routes from one VPN instance to another on the same provider edge(PE) device.

• Convenient in VPN deployment scenarios where BGP route reflector controls how a route originated from one VRF is imported to another VRF on the same provider edge (PE) device.

• Enhances interoperability while replacing non-Junos routers with Junos routers on customer networks.

Overview of BGP accept-own Community Attribute

Per the standard BGP specification, a BGP speaker rejects routes received with the following attributes:

• The originator id set to itself.

• The nexthop attribute same as that of the receiver’s own IP address.

Starting in Junos OS Release 21.4R1, MX480 and MX960 routers accept BGP routes with the accept-owncommunity, defined by RFC 7611, BGP ACCEPT_OWN Community Attribute. The feature enables Juniper routers to accept routes whose ORIGINATOR_ID or NEXT_HOP value matches that of the receiving BGP speaker. For example, when a provider edge (PE) device advertises routes with the route distinguisher of a source VRF, the route reflector attaches the accept-own community, adds more route targets, and re-advertises the routes back to the originator. The provider edge (PE) device can then import the routes into the other destination VRFs, excluding its own.

Per RFC 7611, routes attached with ACCEPT_OWN community should be preferred over routes that do not have the community after the LOCAL_PREF comparison is done in the BGP decision process.