Operation Manual – MulticastH3C S7500E Series Ethernet Switches Chapter 6 MSDP Configuration6-14message containing the multicast packet in an SA message and sends it out. Afterreceiving the SA message, the remote RP decapsulates the SA message and deliversthe multicast data contained in the register message to the receivers along the RPT.The MSDP peers deliver SA messages to one another. Upon receiving an SA message,a router performs RPF check on the message. If the router finds that the remote RPaddress is the same as the local RP address, it will discard the SA message. In theAnycast RP application, however, you need to configure RPs with the same IP addresson two or more routers in the same PIM-SM domain, and configure these routers asMSDP peers to one another. Therefore, a logic RP address (namely the RP address onthe logic interface) that is different from the actual RP address must be designated forSA messages so that the messages can pass the RPF check.Follow these steps to configure the SA message content:To do... Use the command... RemarksEnter system view system-view —Enter MSDP view msdp —Enable encapsulation of aregister message encap-data-enable OptionalDisabled by defaultConfigure the interfaceaddress as the RPaddress in SA messagesoriginating-rpinterface-typeinterface-numberOptionalPIM RP address bydefault6.5.3 Configuring SA Request MessagesBy default, upon receiving a new Join message, a router does not send an SA requestmessage to its designated MSDP peer; instead, it waits for the next SA message fromits MSDP peer. This will cause the receiver to delay obtaining multicast sourceinformation. To enable a new receiver to get the currently active multicast sourceinformation as early as possible, you can configure routers to send SA requestmessages to the designated MSDP peers upon receiving a Join message of a newreceiver.Follow these steps to configure SA message transmission and filtering:To do... Use the command... RemarksEnter system view system-view —Enter MSDP view msdp —Enable the device to sendSA request messagespeer peer-addressrequest-sa-enableOptionalDisabled by default
