HP A6600 Configuration Manual page 58

Figure 19 Changing an RPF route
As shown in Figure 19, when no multicast static route is configured, Router C's RPF neighbor on the path
back to Source is Router A. The multicast information from Source travels along the path from Router A to
Router C, which is the unicast route between the two routers; with a multicast static route configured on
Router C and with Router B as Router C's RPF neighbor on the path back to Source, the multicast
information from Source travels from Router A to Router B and then to Router C.
Creating an RPF route
When a unicast route is blocked, multicast traffic forwarding might be stopped due to lack of an RPF
route. By configuring a multicast static route for a given multicast source, you can create an RPF route so
that a multicast routing entry is created to guide multicast traffic forwarding regardless of whether a
unicast route is available.
Figure 20 Creating an RPF route
As shown in Figure 20, the RIP domain and the OSPF domain are unicast isolated from each other. When
no multicast static route is configured, the hosts (Receivers) in the OSPF domain cannot receive the
multicast packets that the multicast source (Source) sent in the RIP domain. After you configure a multicast
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