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slowpoke115_145's avatar
slowpoke115_145
Icon for Nimbostratus rankNimbostratus
Jun 21, 2014

Multi GTM environments

Hi, could someone give me a very quick overview of how to design GTM in a multiple data centre environment? For example - say we have 10 DC's and put a GTM in each of them, how does GTM function at this level? Does each GTM need a route to the other GTMs management interfaces? How is traffic load balanced at the global level - is it just a case of users automatically connect to their nearest GTM? How does GTM deal with DNS in this way? Does each GTM require it's own DNS IP address? Perhaps each GTM has site based DNS (i.e GTM.NYC, GTM.JAP etc).

 

Finally - what's the purpose of the GTM's having visibility of each other? If a DC is offline for any reason, surely traffic would be automatically redirected to an alternate IP, regardless of the state of GTM? Perhaps this is for site-wide failover or something, are GTM's put in duplicate (or N+1) on each site?

 

I appreciate these are basic questions, but I'm quite new to the design aspect and need a basic overview of where to start (I'm sure I can cope with the configuration points).

 

application delivery
availability
BIG-IP DNS
deployment
design
gtm

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  • SynACk_128568's avatar
    SynACk_128568
    Icon for Cirrostratus rankCirrostratus
    Jun 21, 2014

    Hi ,

     

    1) Gtm provides intelligent load balancing/DNS which for which it will reference the pool and give resolution accordingly .

     

    GTM will listen for dns request on listener ip defined on the GTM .

     

    And there sholud be connectivity between self ip of the GTM 's so that can communicate through iquery .

     

    "How is traffic load balanced at the global level - is it just a case of users automatically connect to their nearest GTM?" For this type of load balancing you can set Topology based load balancing .

     

    what's the purpose of the GTM's having visibility of each other? GTM need to communicate with each other if they are in sync group or meaning that they are sharing configuration . To keep config in sync , to know state of the other devices etc if it is statndlone and are not depend on the other GTM's it is not necessary .

     

    GTM will be load balancing according to the poad balancing method which you have set .