Example: Creating an RPF route

As shown in Figure 32:

• PIM-DM runs on the network.

• All switches on the network support IP multicast.

• Switch B and Switch C run OSPF, and have no unicast routes to Switch A.

• Typically, the receiver host receives the multicast data from Source 1 in the OSPF domain.

Configure the switches so that the receiver host receives multicast data from Source 2, which is outside the OSPF domain.

1. Assign an IP address and subnet mask for each interface, as shown in Figure 32. (Details not shown.)

2. Configure OSPF on Switch B and Switch C. (Details not shown.)

3. Enable IP multicast routing, and enable IGMP and PIM-DM:

   # On Switch C, enable IP multicast routing.

   <SwitchC> system-view
   [SwitchC] multicast routing
   [SwitchC-mrib] quit
   

   # Enable IGMP on the receiver-side interface VLAN-interface 100.

   [SwitchC] interface vlan-interface 100
   [SwitchC-Vlan-interface100] igmp enable
   [SwitchC-Vlan-interface100] quit
   

   # Enable PIM-DM on VLAN-interface 101.

   [SwitchC] interface vlan-interface 101
   [SwitchC-Vlan-interface101] pim dm
   [SwitchC-Vlan-interface101] quit
   

   # On Switch A, enable IP multicast routing.

   <SwitchA> system-view
   [SwitchA] multicast routing
   [SwitchA-mrib] quit
   

   # Enable PIM-DM on each interface.

   [SwitchA] interface vlan-interface 300
   [SwitchA-Vlan-interface300] pim dm
   [SwitchA-Vlan-interface300] quit
   [SwitchA] interface vlan-interface 102
   [SwitchA-Vlan-interface102] pim dm
   [SwitchA-Vlan-interface102] quit
   

   # Enable IP multicast routing and PIM-DM on Switch B in the same way Switch A is configured. (Details not shown.)

4. Display RPF information for Source 2 on Switch B and Switch C.

   [SwitchB] display multicast rpf-info 50.1.1.100
   [SwitchC] display multicast rpf-info 50.1.1.100
   

   No output is displayed because no RPF routes to Source 2 exist on Switch B or Switch C.

5. Configure a static multicast route:

   # Configure a static multicast route on Switch B and specify Switch A as its RPF neighbor on the route to Source 2.

   [SwitchB] ip rpf-route-static 50.1.1.0 24 30.1.1.2
   

   # Configure a static multicast route on Switch C and specify Switch B as its RPF neighbor on the route to Source 2.

   [SwitchC] ip rpf-route-static 10.1.1.0 24 20.1.1.2
   

# Display RPF information for Source 2 on Switch B.

[SwitchB] display multicast rpf-info 50.1.1.100
 RPF information about source 50.1.1.100:
     RPF interface: Vlan-interface102, RPF neighbor: 30.1.1.2
     Referenced route/mask: 50.1.1.0/24
     Referenced route type: multicast static
     Route selection rule: preference-preferred
     Load splitting rule: disable

# Display RPF information for Source 2 on Switch C.

[SwitchC] display multicast rpf-info 50.1.1.100
 RPF information about source 50.1.1.100:
     RPF interface: Vlan-interface101, RPF neighbor: 20.1.1.2
     Referenced route/mask: 50.1.1.0/24
     Referenced route type: multicast static
     Route selection rule: preference-preferred
     Load splitting rule: disable

The output shows that the RPF routes to Source 2 exist on Switch B and Switch C. The routes are the configured static routes.