156Step Command Remarks3. Enable auto-RP. auto-rp enable Disabled by defaultConfiguring C-RP timers globallyTo enable the BSR to distribute the RP-set information within the PIM-SM domain, C-RPs must periodicallysend C-RP-Adv messages to the BSR. The BSR learns the RP-set information from the received messages,and encapsulates its own IP address together with the RP-set information in its bootstrap messages. TheBSR then floods the bootstrap messages to all PIM routers in the network.Each C-RP encapsulates a timeout value in its C-RP-Adv messages. After receiving a C_RP-Adv message,the BSR obtains this timeout value and starts a C-RP timeout timer. If the BSR fails to hear a subsequentC-RP-Adv message from the C-RP when this timer times out, the BSR assumes the C-RP to have expired orbecome unreachable.The C-RP timers need to be configured on C-RP routers.To configure C-RP timers globally:Step Command Remarks1. Enter system view. system-view N/A2. Enter public network PIM viewor VPN instance PIM view.pim [ vpn-instancevpn-instance-name ] N/A3. Configure the C-RP-Advinterval. c-rp advertisement-interval interval Optional60 seconds by default4. Configure C-RP timeout time. c-rp holdtime interval Optional150 seconds by defaultFor more information about the configuration of other timers in PIM-SM, see "Configuring PIM commontimers."Configuring a BSRA PIM-SM domain can have only one BSR, but must have at least one C-BSR. Any router can beconfigured as a C-BSR. Elected from C-BSRs, the BSR is responsible for collecting and advertising RPinformation in the PIM-SM domain.Configuring a C-BSRC-BSRs should be configured on routers in the backbone network. When you configure a router as aC-BSR, be sure to specify a PIM-SM-enabled interface on the router. The BSR election process issummarized as follows:1. Initially, every C-BSR assumes itself to be the BSR of this PIM-SM domain and uses its interface IPaddress as the BSR address to send bootstrap messages.2. When a C-BSR receives the bootstrap message of another C-BSR, it first compares its own prioritywith the other C-BSR's priority carried in the message. The C-BSR with a higher priority wins. If a
