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venkat_ch_24285's avatar
venkat_ch_24285
Icon for Nimbostratus rankNimbostratus
Aug 31, 2016

How to get Pool member id

Hello All,

 

I have a f5-Loandbalancer, in which i have create a pool with 3 pool members. Could you check my below queries

 

  1. Will F5 have a same routing value for pool members, i meant for pool member-1 assume routing value according to F5 is 1234.abcd then will this same value be used every time if F5 wants to route to pool membser-1 any time?

Reason for above question is that i have a job which will store all these routing information of pool members and will provide information to F5 based on some our internal logic.

 

Are these routing information static for pool members?

 

If new pool member is added then how new value gets calculate and where i can view this information in F5?

 

Please help me.

 

Regards, Ch.Venkat.

 

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  • IainThomson85_1's avatar
    IainThomson85_1
    Icon for Cumulonimbus rankCumulonimbus
    Aug 31, 2016

    Really sorry, I actually can't understand your requirements. The F5 is a full proxy load balancer, it doesn't "Route" as such, (Although yes, there is a routing table, and you can enable ZeBos etc)

     

    What do you exactly want to achieve ?

     

  • venkat_ch_24285's avatar
    venkat_ch_24285
    Icon for Nimbostratus rankNimbostratus
    Aug 31, 2016

    Hi,

     

    I want to send an information to Loadbalancer to select a specific pool member. How to achieve it?

     

    Regards, Ch.Venkat.

     

  • Samir_Jha_52506's avatar
    Samir_Jha_52506
    Icon for Noctilucent rankNoctilucent
    Aug 31, 2016

    Unable to understand requirement. But based on the traffic condition you can select any pool member from VIP. Paste your requirement.

     

    • venkat_ch_24285's avatar
      venkat_ch_24285
      Icon for Nimbostratus rankNimbostratus
      Aug 31, 2016

      Hi,

       

      I want to send an information to Load balancer(f5) to select a specific pool member. How to achieve it?

       

      Regards, Ch.Venkat.

       

    • IainThomson85_1's avatar
      IainThomson85_1
      Icon for Cumulonimbus rankCumulonimbus
      Sep 02, 2016

      What information ? is it something that you can pick up with an iRule ?

       

      /uri ? content ? what are you sending ?

       

  • venkat_ch_24285's avatar
    venkat_ch_24285
    Icon for Nimbostratus rankNimbostratus
    Sep 02, 2016

    Hello All,

     

    I'm sorry, i couldn't make my requirement easy, lemme give my requirement here.

     

    I have a f5-Loandbalancer, in which i have create a pool with 3 pool members. When i make calls to loadbalancer, those calls gets distributed 3 pools based on the round-robin alogorithm (assume if i set round-robin)

     

    Case-1 : If i make cookie-insert as persistence then i get the bigipcookie in response of first call, later i can use this(send cookie in requests) bigipcookie to send the call to same pool member.

     

    Case-2 If i use hash cookie-persistence has persistence method then hashvalue of the responsecookie is calculated and it maps to routing pool information in first call. In later calls if same cookie is available in request then again hashvalue is calculated and routing table uses the previous information and sends call to same old pool member.

     

    My requirement:

     

    In case-2 LB calculating the hash value of cookie and mapping it to routing information. Assume call went to pool member-1 and cookie hash value is xyz then mapping is

     

    xyz-->routing to pool member-1

     

    Now, i don't want to use above methods but want to have my own routing. Implies i want to know how F5 calculating or defining the pool member routing information.

     

    So that i send that pool member routing information in the request. For example, if if want to send a particular request to pool member-2 then i hardcode the routing information of pool member-2 in the request then F5 sends call to pool member-2 directly.

     

    The routing information, i can send in cookie. basically i need to know two things

     

    1. How F5 knows it's pool members identity
    2. Are those values are static?

    Regards, Ch.Venkat.

     

  • IainThomson85_1's avatar
    IainThomson85_1
    Icon for Cumulonimbus rankCumulonimbus
    Sep 02, 2016

    Write a custom iRule that reads the value of the cookie that's been inserted and direct that from there.

     

    Although in effect you're not really load balancing then... You're not really distributing load as the servers are doing different things.