nerdexam
Cisco

300-420 · Question #219

A network engineer must design an MSDP multicast solution to provide RP resilience in a network with two separate domains. Also, multicast sources and receivers must register with the local RP…

The correct answer is B. Configure the RP loopback interface with the same IP address/32, and traffic will route to the. The solution described is Anycast RP with MSDP. In this design, multiple RPs in different PIM domains are each configured with the same /32 IP address on their loopback interfaces. Because it is a /32 host route, unicast routing (e.g., OSPF) causes each source and receiver to…

Advanced Addressing and Routing Solutions

Question

A network engineer must design an MSDP multicast solution to provide RP resilience in a network with two separate domains. Also, multicast sources and receivers must register with the local RP. Which solution must the engineer choose?

Options

  • AConfigure the RP has value to 0, and traffic will route to the closest RP
  • BConfigure the RP loopback interface with the same IP address/32, and traffic will route to the
  • CConfigure the RP group ranges to split the multicast traffic, and traffic will route to the longest
  • DConfigure the RP priority with the same value, and traffic will route to the closest RP

How the community answered

(46 responses)
  • A
    4% (2)
  • B
    80% (37)
  • C
    13% (6)
  • D
    2% (1)

Explanation

The solution described is Anycast RP with MSDP. In this design, multiple RPs in different PIM domains are each configured with the same /32 IP address on their loopback interfaces. Because it is a /32 host route, unicast routing (e.g., OSPF) causes each source and receiver to register with their topologically closest RP - this is the 'anycast' behavior. MSDP sessions are then established between the RPs so they can share source-active (SA) state, enabling receivers anywhere to learn about sources registered with any RP in the network. This provides both local registration (sources/receivers use the nearest RP) and RP resilience (if one RP fails, traffic is rerouted to the surviving RP with the same anycast address). Setting the RP hash value to 0 (A) or adjusting priority (D) relates to PIM BSR/Auto-RP election, not Anycast RP. Group range splitting (C) divides multicast traffic but does not inherently provide resilience.

Topics

#MSDP#Multicast RP Resilience#Anycast RP

Community Discussion

No community discussion yet for this question.

Full 300-420 Practice