Printer FriendlyEmail Article Link

Spirent TestCenter: Is there a command to send a PIM hello message on the fly before the 30s interval expires?

  • Spirent TestCenter
  • PIM
  • Scenario: PIM router in DUT establishes neighborship with Spirent PIM router.
    If PIM is shutdown in DUT and comes back- Hello message with new GenId is generated by DUT.
    • Spirent doesn't respond with Hello message immediately. It responds after its hello timer (30 secs).
  • There is no on the fly command to send a Hello.
    RFC-4601 for PIM-SM
    Section 4.3.1 – Sending Hello Messages
    PIM Hello messages are sent periodically on each PIM-enabled interface.
    A per-interface Hello Timer (HT(I)) is used to trigger sending Hello  messages on each active interface.  When PIM is enabled on an  interface or a router first starts, the Hello Timer of that interface  is set to a random value between 0 and Triggered_Hello_Delay.  This prevents synchronization of Hello messages if multiple routers are powered on simultaneously. After the initial randomized interval, Hello messages must be sent every Hello Period seconds.  The Hello Timer should not be reset except when it expires.
  • "To allow new or rebooting routers to learn of PIM neighbors quickly, when a Hello message is received from a new neighbor, or a Hello message with a new GenID is received from an existing neighbor, a new Hello message should be sent on this interface after a randomized delay between 0 and Triggered_Hello_Delay."
  • Couple Options to send Hellos when needed:
    1. Use a raw streamblock to simulate a Hello
    2. To keep the Spirent Neighbor up, you can right click on the device to stop Hellos then stop the PIM device.
      By stopping the Hellos, it will not say goodbye when you stop the PIM device which will keep all the Neighbors thinking the Spirent side is still up.
      Once the DUT brings up PIM, you can start Spirent PIM device which will then send a Hello.
    3. For #2, you can use the command sequencer to automatically wait for DUT to send a Hello, then bring up Spirent side which will send a Hello


Product : Spirent TestCenter,PIM,Multicast