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Notable Replies

  1. Hi Rene,

    What is the use of the null0, I learned that is the trash can of the packets but never fully understand when will I use it.

    Please advise

  2. Hi Alfredo,

    When you send something to the null interface then those packets are discarded. It can be useful if you want to advertise something that you don't have.

    When you create a static route you need a valid next hop or it can't be installed in the routing table. Because of this, using the null interface as next hop will help.

    It's also useful when you create summary routes. With a summary, it's possible that you receive traffic for networks that you don't have. In this case the packets can be discarded to the null interface.


  3. hi

    will I need to advertise the internal routing network into BGP
    for example internal EIGRP is using subnet

  4. Hi,

    How do I advertise public IP to a peer? for example, my server should NAT to <public-IP> and routed to neighbor.

    The router only knows the network as connected.


  5. Hlw Rene,

    Hope you are doing great ..

    One questions ..

    The BGP router will trigger a routing update to neighbor if belonging subnets are flap again & again in internal domain ?? How could we get routing upadate stability if BGP router always send Update. Could you please explain more on it .Many thanks


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