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2funky_105078's avatar
2funky_105078
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Apr 22, 2014

GTM: avoiding flapping DNS answers with RTT method

I am in the need to understand how GTM metrics work for GTM LDNS probes.   1) how they can be logged the decision? I am using 11.2 but moving fast to 11.4.1.. :)   2) Lets make an example. if...
BIG-IP DNS
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  • Cory_50405's avatar
    Cory_50405
    Apr 23, 2014

    The only solution I could see in your situation is to break your single pool into three pools, and either stick with RTT and enable persistence at the wide IP, or switch to topology. Either one should get you some more consistency.

     

Cory_50405's avatar
Cory_50405
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Apr 23, 2014

You can apply topology based load balancing at the wide IP level to select a pool. You can then apply RTT load balancing at the pool level to select a member. So they can be used in conjunction depending on your setup.

 

If your pools are built according to data center, then topology could send users from a certain country/state/etc. to a certain pool. The pool could then use RTT to send you to the lowest latency pool member.

 

In your example, I don't see a way for GTM to accomplish what you wish to do.