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jianhua's avatar
jianhua
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Oct 03, 2022

F5 GTM support Operator identification?

Whether GTM can return A records according to the operator. For example, the IP address of a telecommunication server responds to the IP address of a telecommunication server. Mobile or Unicom, respond to the corresponding IP address

  • Hello,

    Could you please clarify more? please explain the example in detail to understand your request.

    • jianhua's avatar
      jianhua
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      There is a scenario, such as an enterprise with multiple bases (Beijing and Shanghai), the desired effect: when a user initiates a request, the IP in the A record that F5 can respond to is a DNS request from Beijing IP. User-defined Beijing server IP. For a DNS request from Shanghai IP, the IP in the A record of the response is the user-defined Shanghai server IP. It is not a polling or active-standby mode.

  • I think he's asking about deterministic response.  In theory, the BIND underpinnings of gtmd should allow you to create a view - F5 DNS has used 'external' as the default forever, iirc - to attach a topology to. A topology can be a range - even a /32. Using a view will allow you to administer zone files - and WIPs, etc - that are identical, but only work for the topology that they are attached to. 

     

    This should still be somewhat current.. Should at least get you started:

    K14421:  Achieving split DNS behavior through BIG-IP DNS wide IPs

    • jianhua's avatar
      jianhua
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      Thanks a lot, exactly as described in K14421. The DNS response needs to be split according to the client IP. But there is a problem: how does F5 define the client IP address range? Does a similar address library exist? I know that there is a regional IP database in AFM, is there one in GTM?

      • AubreyKingF5's avatar
        AubreyKingF5
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        Topolgy. That is how you assign IP ranges. Just make a new topology and attach it to the view.  We have customers that use this for data sovereignty all the time. I have worked with an on-line entertainment provider that managed PoP response based on topologies with (then) GTM.