Forum Discussion

SS11's avatar
SS11
Icon for Nimbostratus rankNimbostratus
Jul 30, 2019

LTM Policy to forward the request to particular member in a pool

I am new to LTM Policies and i would like to know how to achieve the below conditions in LTM Policies method;

 

If the URI matches it should forward to particular member in a Pool.

 

Query - Do we need to create two forward in policy ( First forward to Pool and second forward to member in the pool) when the condition is matched?

application delivery
BIG-IP
LTM
policy
    • SS11's avatar
      SS11
      Icon for Nimbostratus rankNimbostratus
      Jul 30, 2019

      Hi,

       

      Thanks. The BIG-IP version is 13.1.1.4

       

      Thank You

       

  • Stanislas_Piro2's avatar
    Stanislas_Piro2
    Icon for Cumulonimbus rankCumulonimbus
    Jul 30, 2019

    Hi,

     

    pool assignment and pool member selection is done for the whole tcp connection except if you use one connect profile...

     

    if à request which doesn’t match a policy rule (or an irule condition), it will use pool / member selected by the previous request in the same connection...

     

    so so if you want to define 2 different behaviors depending on the uri, define 2 different rules

  • cjunior's avatar
    cjunior
    Icon for Nacreous rankNacreous
    Jul 30, 2019

    Hi,

    I understood you are trying to replace a know iRule condition with LTM policy, right?

    If you can't "Forward traffic to node" in a rule by default, maybe the rule bellow save the day.

     

    0691T000005lk8PQAQ.png 

     

    The goal is to run the tcl pool command setting a member on the rule to a specific path on condition.

     

     ,

    What your opinion about this approach?

     

    Thank you.

    • SS11's avatar
      SS11
      Icon for Nimbostratus rankNimbostratus
      Jul 30, 2019

      Hi,

       

      Thanks for the solution and I am planning to use Policy instead of irule for new requirement to check the benefits.

       

      Looking for clarification on Variable option;

       

      1.Set Variable named should be specific to any name? because i see the conditions equal to pool member.

      2.Is there any option apart from Variable because i see below guidelines when using TCL command substitution;

       

      • Memory and CPU capacity determine a maximum number of rules for active policies; however, excessive Tcl command substitutions can degrade performance.
      • Tcl command substitutions are primarily intended for reading and returning data.

       

      Thank You.

       

      • cjunior's avatar
        cjunior
        Icon for Nacreous rankNacreous
        Jul 30, 2019

        Hi,

        Here my answers:

         

        .Set Variable named should be specific to any name? because i see the conditions equal to pool member.

        Yes, it is disposable anyway.

         

        2.Is there any option apart from Variable because i see below guidelines when using TCL command substitution;

        I can't see another than built-in way to send to a node directly. (the "Forward traffic to node" action)

        I just can say that approach is a workaround to reach the similar we can do in iRule.

        I usually use "Set variable" mixed to an iRule, to control HTTP redirect 301, for example.

         

        Regards.