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Forum Replies

  1. Thanx a lot Rene … Excellent explanation … It was so systematic … to the point … and U made it so easy to understand … Great work

  2. Great topic. Thanks Rene

  3. Hi Rene,
    when we write

    router bgp 100
    network mask backdoor

    is that mean changing the AD to 200 for all network or only default route?

  4. Why did the AD go from 20 to 200 at the end? How did the backdoor command influence that?

  5. andrew says:

    What you are seeing is the effect of the backdoor command. The backdoor command changes the BGP administrative distance of the selected route from 20 to 200. 200 is chosen because that AD is worse than any IGP’s AD. This way, BGP will be used as a last resort if either static or other IGP routing mechanisms become unavailable.

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