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  1. jeff says:

    Type 5 – External LSA: also known as autonomous system external LSA: The external LSAs are generated by the ASBR.

    When you generate a default route. You are advertising a route that looks like it from another network. In the example the default route could represent the ISP connection. R1 would represent the ASBR and generate type 5 LSAs (default route).

    Hope this helped to answer your question.

  2. If you have a DMVPN network and a spoke is receiving a bunch of OSPF routes, along with default route (default-info originate), but don't want a default route, but can't change that default-information originate command on the hub, can you use some sort of route map or prefix list that you could configure on the spoke to block the default route being advertised?

    I hope this makes sense..
    Thanks,
    Shawn

  3. andrew says:

    Shawn,
    Yes, you can do this, sort of :slight_smile:

    Remember that a requirement for OSPF is that all members in the same area must have identical databases (and I presume that your DMVPN hub and spokes are in the same area). So the best you are going to be able to do is keep that default route from getting installed in the routing table, even though it will still be present in the OSPF database. I recommend using a prefix-list to do it. Here's a sample:

    (config)#ip prefix-list PL_NODEFAULT deny 0.0.0.0/0
    (config)#ip prefix-list PL_NODEFAULT permit 0.0.0.0/0 le 32
    (config)#router ospf 1
    (config-router)#distribute-list prefix PL_NODEFAULT in
  4. Andrew, that worked perfectly. Thank you so much!

    S

  5. sims says:

    Hi
    What if we have different area and core distribution access layer .
    Where we have to put the default originate command
    Thanks

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