I worked on a network with the following protocols : OSPF, IGMP, PIM sparse dense mode, Anycast RP and MSDP. Topology is made of rings with four RP. On each sites we've got an MRV box to convert FastEthernet to FO. Or it appears that when we disconnected the FO on the MRV, some sites disappears from the RP ( sh ip msdp sa-cache). Have you any ideas ?
Thanks for your help.