Configuring Multicast Routing and PIM
Use the following command to enable multicast routing:
(config)# ip multicast-routing
PIM mode must be configured at each interface with the following
command. Configuring PIM on an interface also enables Internet Group
Management Protocol (IGMP) on that interface:
(config-if)# ip pim {sparse-mode | dense-mode | sparse-dense-mode}
When using sparse mode, an RP must be specified. A router knows that it is
an RP when it sees its own address in the command:
(config)# ip pim rp-address ip-address