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Forum Discussion

Devlin_T_149357's avatar
Devlin_T_149357
Apr 06, 2018

Which Local DNS Does GTM/DNS Use?

Hi all

 

In a situation where we have a client that sends its DNS query to its local DNS, and that LDNS then forwards to another DNS server, which then has a sub-zone delegated to the GTM/DNS; will the GTM/DNS see the LDNS, as used for Topology load balancing, as the first or second LDNS server?

 

Thank you.

 

application delivery
BIG-IP DNS

1 Reply

  • Stanislas_Piro2's avatar
    Stanislas_Piro2
    Icon for Cumulonimbus rankCumulonimbus
    Apr 06, 2018

    Hi,

     

    each DNS forwarder hides the source requester.

     

    If :

     

    • the client requests ForwarderA
    • ForwarderA requests ForwarderB
    • ForwarderB requests root server,then zone servers and sub-zone servers (GTM)

    GTM will see ForwarderB as client.

     

    DNS forwarder role is like a proxy, DNS server Role is the server which have the database.

     

    If you create a sub-zone gslb.company.com with GTM as NS records, the request is not done by company.com server, but by the forwarder which receive NS answer.