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Multiple RR Clusters

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  • 1.  Multiple RR Clusters

    Posted 01-18-2020 03:36

    Hi, I am struggling to understand this question, can anybody help me? 

     

    Screenshot 2020-01-18 at 11.12.10.png


    #reflector
    #Route
    #cluster
    #BGP


  • 2.  RE: Multiple RR Clusters

     
    Posted 01-18-2020 21:27

    I can see why you would be confused. I don't think this question is worded correctly.

     

    I am thinking that the question should say: "which 3 routers would R1 need to peer with?". 

     

    If no-client-reflect is configured on RR1 and RR2, R1 would need to have BGP sessions with R2, and R3 so that R2 and R3 can receive the routes advertised by R1.  Thus, R1 would need to peer with R2, R3, RR1 and RR2.  

     

    RR1 on the other hand, would need to peer with R1, R2, R3, and RR2 regardless of wether no-client-reflect is configured or not. 

     



  • 3.  RE: Multiple RR Clusters
    Best Answer

    Posted 01-19-2020 00:37

    Hello,

     

    The way I read the question is:

    1/ no-client-reflect makes sense only when clients are peering with each other. So, if R1,R2 and R3 are RR1-clients, and only RR1 has no-client-reflect knob enabled, then R1,R2 and R3 must be peering with each other.

    2/ if RR1 peers with RR4, then there is no need for RR1 to peer with R5 and R6.

    3/ so, this leaves us with a choice of RR4, R1 and R2 for RR1 to peer with.  Such scheme leaves out R3 but R3 can peer with RR2 and be well fed with routes.

    HTH

    Thx

    Alex



  • 4.  RE: Multiple RR Clusters

    Posted 01-21-2020 10:56

    Hi,

     

    Im not quite understanding still, can you explain in a different way please? 

     

    Thanks for helping so far



  • 5.  RE: Multiple RR Clusters

    Posted 01-21-2020 21:41

    Hello,

     


    @NetworkMan23 wrote:

    Hi,

     

    Im not quite understanding still, can you explain in a different way please? 

     

     


     

    Certainly. This question is an example of how NOT to build a network, or rather how do You minimize the adverse impact of previous decisions made.

    It is clear that with restrictions imposed on RR1 (can have only 3 peers and only from a given list) it cannot possibly serve its proximate clients R1, R2 and R3 _AND_ at the same time pass enough routing  information to the right half of the network.

    So, the choice needs to be made and I explained my choice in my previous post.

    HTH

    Thx

    Alex