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Kevin_Nail's avatar
Kevin_Nail
Icon for Nimbostratus rankNimbostratus
Sep 22, 2014

GTM Global sync group help

I have sync group already established here in the US. Now we are adding 2 additional GTMs in Asia for a truly Global sync group. But I am a bit confused on the best way to do this. In our current sync group we have 2 zones: gtmzone.mycompany.com (for company wide names) and gtmzone.localsite.mycompany.com (for local sites). I don't know if that was the best way to set it up but we have hundreds of records in each zone. So here are my concerns or questions really on adding additional GTMs:

 

  1. Will adding another zone that is located in Asia mess up any resolutions in either of the current zones? Or will ALL GTMs be able to resolve queries in either local site as well as the global zone?

For example, we would add: gtmzone.localsite2.mycompany.com with a new SOA record for that zone and NS records of all 5 GTMs. So then our zone records would look something like this:

 

Gtmzone.mycompany.com

 

Gtmzone.localsite.mycompany.com

 

Gtmzone.locasite1.mycompany.com

 

With each zone having its own master record and sharing (or having the same) 5 NS records and 5 A records

 

  1. Or should I remove the one local site zone and have just one global zone and use CNAMEs that point to the local sites? Or would that work if I don’t have the local sites in the GTM anymore?

I think I’m on the right track here. But need some expert guidance. Additionally, we may have/add other GTMs in the future, so what we do here will be a model going forward.

 

4 Replies

  • Kevin_Davies_40's avatar
    Kevin_Davies_40
    Icon for Nacreous rankNacreous
    Sep 22, 2014

    Typically when you add a new GTM its a a two step process. First you tell the existing GTM about the new device by added it as a Single BIGIP server with virtual server discovery disabled. Then you run a command on the new GTM called gtm_add with the IP address of the existing GTM. The instructions for doing this can be found in the manual pages of each BIGIP release. This command completely overwrites the configuration of the newly added unit with that of the existing GTM and then they are kept in Sync.

     

    See "Adding a new BIG-IP GTM to a GTM Synchronization Group"

     

    When it comes to your zones they will automatically be propagated to your GTM's through the sync-group. As long as you have the option selected on the Sync page configuration called "Synchronize DNS Zone Files". This is on by default.

     

  • Kevin_Nail's avatar
    Kevin_Nail
    Icon for Nimbostratus rankNimbostratus
    Sep 23, 2014

    Yes, I understand how to add a GTM to a sync group. That was not my question but thank you for taking the time to respond. I appreciate that.

     

    • Kevin_Davies_40's avatar
      Kevin_Davies_40
      Icon for Nacreous rankNacreous
      Sep 23, 2014
      The answer to your question lies within. In regards to the first question... No. In regards to the second question. Any zones you create are automatically replicated across GTM's. How you choose to structure resilution is entirely up to you as long as it follows correct DNS behaviour. It usually comes down to an administrative choice rather than a GTM one. In any case before you go down a path which changes the DNS domains I suggest you run it up on a test platform it to make sure it works as you expect. Eg GTM understands it. The information you have provided here is not enough to say one way or the other. Provide actual before and after DNS examples (sanitized) and then we will have a better idea of what DNS changes you propose and we can comment further.
  • Kevin_Nail's avatar
    Kevin_Nail
    Icon for Nimbostratus rankNimbostratus
    Sep 23, 2014

    Kevin, Thanks for the information!

     

    Here is a scenario:

     

    GTM has 2 zones, the difference being that one is used for Global and one is used for site specific. For example:

     

    gtmzone.mycompany.com (global zone) gtmzone.local.mycompany.com (site local zone)

     

    with records such as:

     

    in the Global zone: app1.gtmzone.mycompany.com with an alias of app1.gtmzone.local.mycompnay.com app2.gtmzone.mycompany.com

     

    in the Local zone:

     

    app3.gtmzone.local.mycompany.com app4.gtmzone.local.mycompany.com

     

    So with that context:

     

    1. If we add another local site zone in Asia such as gtmzone.asia.mycompany.com

    What affect would it have, if any, on the other 2 zones?

     

    1. If it has any affect, should we or if we remove the gtmzone.local.mycompany.com would the GTM still be able to resolve the local site names such as the alias.

    app1.gtmzone.mycompany.com with an alias of app1.gtmzone.local.mycompnay.com