Printer FriendlyEmail Article Link

Spirent TestCenter: Why BFD with OSPF is not sending any messages?

  • OSPF with dependent BFD
  • BFD does not start sending any messages until OSPF comes up first.
  • Note that there is a bit in BFD messages that indicted as being Dependent or Independent type messages.
    • It's been seen that even with one side as Dependent and the other side as Independent BFD still come up.
      • Both sides recognize the BFD messages and brings up the sessions.
    • This does not mean that some devices may prevent the sessions from coming up with mismatched types.
  • If BFD and OSPF do not come up whether its Dependent mode or Independent mode:
    • OSPF should be the first to be analyzed for any issues.
      • Case 1: MTU size should match
      • Case 2: Router Priority need to be other than zero if participating in DR election.
      • Case 3: Database Description Master/Slave bit is determined by higher router ID.
        • Make sure the lower router ID is able to become Slave
        • Note that this is different from Designated Router indication.
        • A DR can still be a Slave for Database Description behavior.
    • In Dependent mode, BFD is not transmitted until OSPF comes up first.

Product : Routing,Spirent TestCenter,OSPF,BFD