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Forum Replies

  1. Hi Jason,

    These have to be match yes, otherwise no neighbor adjacency is established.


  2. Dear Rene,

    Many Thanks to you .One question…

    Why Neighbor will not form if Hello/dead Mismatch ?? Could you please explain behind the reason on it ? I think if Hello/Dead is not same on both end then there could be operational related problem like One router release neighbor first while other router still wait, right ??


  3. Hi Mohammad,

    A good question. I am referring to you to RFC which is a type of publication from the Internet Engineering Task Force (IETF) and the Internet Society (ISOC), the principal technical development and standards-setting bodies for the Internet.
    On April 1998, they have created the publication RFC 2328 for OSPF version 2, and on point 9.5 they spoke about “Sending Hello Packets” as following:

    “Hello packets are sent out each functioning router interface. They are used to discover and maintain neighbor relationships.[6] On broadcast and NBMA networks, He

    ... Continue reading in our forum

  4. Hi Rene,

    I have two established neighbors, just take dead interval as 40 secs if dr goes down for 30 secs bdr will wait for dead interval to proceed further or will it become as dr ??

  5. Hi Karthik,

    If your dead interval is 40 seconds then OSPF will wait for 40 seconds until it declares the neighbor as dead, deleting the neighbor adjacency. If you want to see this in action, connect two routers to each other with a switch in the middle, then disconnect one of the links :slight_smile:


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