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Indirect-next-hop

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  • 1.  Indirect-next-hop

    Posted 07-27-2011 13:32

    Hi experts

    can anyone please explain to me what is the use of  " indirect-next-hop " in simple English Smiley Happy

    Thanks



  • 2.  RE: Indirect-next-hop
    Best Answer

     
    Posted 07-27-2011 14:28

     

    Imagine you have thousands of routes which all point to the same next-hop.  Now normally, without indirect-next-hop capability, if the next-hop changed due to some reconvergence in the network, you will have to update the next-hop for many thousands of routes, which could take a lot of CPU cycles to complete.

     

    Route1 ---> next-hop x.x.x.x

    Route2 ---> next-hop x.x.x.x

    .............

    Route x ---> next-hop x.x.x.x

     

    Now, imagine using simply a pointer, where all these thousands of routes simply point to this pointer.  Now this pointer itself actually references the actual next-hop in use.  Now, if the next-hop changes, instead of having to change the next-hop to thousand of routes, we can simply change the next-hop that the pointer is pointing to.  The actual routes still continue to point to this single pointer so there is no need to modify many thousands of routes.  In this case we just need to make one change, which saves many CPU cycles and dramatically improves convergence times, especially as the number of routes grow...

     

    Route1 ---> Indirect Next Hop Z

    Route2 ---> Indirect Next Hop Z

    .............

    Route x ---> Indirect Next Hop Z

    Indirect Next Hop Z ----> next-hop x.x.x.x

     

    HTHs.



  • 3.  RE: Indirect-next-hop

    Posted 07-27-2011 14:46

    Thanks alot sfouant i think now it's clear  Smiley Happy 

    thanks again



  • 4.  RE: Indirect-next-hop

     
    Posted 07-27-2011 16:30

    @ralwarrag wrote:

    Thanks alot sfouant i think now it's clear  Smiley Happy 

    thanks again


    Cool... don't forget to give me kudos... hehe 🙂



  • 5.  RE: Indirect-next-hop



  • 6.  RE: Indirect-next-hop

     
    Posted 07-31-2011 22:24
    Vey nice find! Thanks Surya!


  • 7.  RE: Indirect-next-hop

    Posted 08-08-2020 06:23

    I know this is almost a decade old now, but it was so much easier to understand than the official literature.

    Thanks 🙂