Run PIM-SSM on either all switches in the domain or only on the edge routers. If you use a mix of PIM-SSM and PIM-SM switches in the domain, run PIM-SSM on all the edge routers and run PIM-SM on all the core routers.
Important
A PIM domain with edge routers running PIM-SM and core routers running PIM-SSM does not operate properly. If you prefer or require a mixed PIM-SM and PIM-SSM topology, run PIM-SSM on the edge switches and PIM-SM in the core. Ensure a valid RP configuration exists for groups that exist outside of the SSM range. If a valid RP configuration exists, the SSM switches process the joins in SM mode. If no RP exists, the SSM switches drop the reports.
Static source groups cannot conflict with SSM channels. If you configure a static source group or an SSM channel, the switch performs a consistency check to make sure no conflicts exist. You can map one group (G) to different sources or multiple groups to a single source for both static source group and an SSM channel.