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Forum Replies

  1. Hi Rene,

    I have some vague about full update and partial update ?
    Do you mean :-
    1 - The full update always send using unicast after neighbor adjacency formed ?
    2 - The partial update always send using multicast when there is a change in the topology ? and if we use static neighbors the partial update will be sent using unicast ? that’s right ?
    If there is wrong correct me please ?


  2. Hello Clement.

    There are differing opinions as to how many and what type of EIGRP packets exist. Some refer to five, others to six. Some group Request packets and Query packets together. Some group ACK and Hello packets together (since ACK is basically an empty hello packet). Some just don’t mention Request packets. It really depends on who you ask.

    Cisco’s official documentation states that there are five packet types:

    * Hello/Acks
    * Updates
    * Queries
    * Replies
    * Requests

    Although Cisco’s official CCNA curriculum gives the following list:

    * Hello
    * Acknow

    ... Continue reading in our forum

  3. Hi
    I’m bit confuse about Acknowledgements.
    ACK packets are used to acknowledge the receipt of update, query and reply packets.
    In case it use to acknowledge the receipt of query, does the router will send ACK first or it send Reply fist or it will send ACK and Reply in the same time ?

  4. Hi Heng,

    You can see this with a quick Wireshark capture: eigrp-query-reply.pcapng

    These are two routers using IP addresses and

    Once loses a route (, it sends the query to first responds to the query with an ACK. Wireshark shows the ACK as Hello (5), don’t let this confuse you…this happens because the EIGRP hello and ACK packet both share the same opcode. responds with a reply, which is ACKed by as well.

    I hope this helps!


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