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Forum Replies

  1. Rene,

    I did a test with two routers in GNS3 to see what kind of packets are exchanged between the two routers. I noticed that first there is an exchange of Hello Packets (to destination address You are mentioning that there is a unicast response Hello packet. The only unicast messages I could find are the DBD and the LS packets.


  2. Kishor,
    I assume you mean the “ExStart” or “Exchange” state, so I will write about those. If OSPF is having an authentication problem, you will not see the routers stuck in ExStart or Exchange. In fact, you won’t see anything at all. The output for “show ip ospf neighbors” will just be blank (if a neighbor relationship hadn’t already formed). If a neighbor relationship already formed, and then an authentication problem is introduced, the neighbors will just drop once the dead interval is reached. The reason, in both cases, is because if there is an authent

    ... Continue reading in our forum

  3. very good explanation thanks!

  4. Hello Laz,

    Well explained, let me do the labbing for the same topology.
    Thanks alot.


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