# Understanding the Conditions for Advertising RT-MEM-NLRI Routes

The following conditions must be met for routes in the route-target address family to be advertised to a BGP peer:

1. The BGP peers have successfully negotiated the route-target address family.
2. The import route-target list for the IPv4 VRF is not empty or is transitioning to empty.

In a VRF, a RT-MEM-NLRI attribute represented by (origin AS number:route target) is advertised for every route target added to the VRF's route target import list when the preceding conditions have been met.

A withdrawal for the RT-MEM-NLRI attribute is generated when the route target is removed from this VRF's import list.