In Scenario 4, RP1 has a default peer plus an access list. The list permits RP4 so the RPF check is
disregarded for active sources from it, but RP5 (and all others because of the implicit deny all) are
subject to the RPF check and fail, so those active sources are rejected.
Figure 80. MSDP Default Peer, Scenario 1
Multicast Source Discovery Protocol (MSDP) 581