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Richard_75751's avatar
Richard_75751
Icon for Nimbostratus rankNimbostratus
Jun 23, 2014

dns express - gtm as secondary dns server

Hi Guys,

 

I would like to configure gtm to use dns express and act as secondary dns server. The primary dns server is running microsoft intergrated DNS. dns express will be used to transfer any forward lookup for wide-ip load balancing request and non-load balancing request will forward to primary dns (microsoft). My questions are:

 

  • using dns express, does the gtm make a copy of the primary dns zones or does it simply forward requests to gtm? how does it work?
  • will the non-load balancing requests from the client go to the GTM and gtm will forward to the primary dns?
  • has anyone setup gtm with dns express with microsoft dns?

Thanks,

 

Richard

 

5 Replies

  • Kevin_Davies_40's avatar
    Kevin_Davies_40
    Icon for Nacreous rankNacreous
    Jun 23, 2014

    I think you may have Wide-IP confused with DNS express. Wide-IP is intelligent resolution for FQDN hosts to resources monitored by it. Be it LTM's or any other device. If it cannot find a matching Wide-IP name then it falls back to other DNS resolution methods such as DNS express.

     

    DNS Express acts a nameserver on behalf of your existing nameservers. It will become a secondary for the domains so it will take a copy of the entire zone file for any domain it is handling.

     

    I am not sure what you gain from forwarding the requests to the internal Microsoft server. You are better off using DNS express for those domains as well. A lot of companies do it this way to protect their internal name servers and utilise the high performance and speed of GTM.

     

    • Richard_75751's avatar
      Richard_75751
      Icon for Nimbostratus rankNimbostratus
      Jun 23, 2014
      Thanks Kevin, with using dns express, will the gtm response to all dns queries on behalf of the primary dns? (wide-ip and non-load balanced traffic.). The SOA will still remain on the primary dns correct? I cant find any sample configs using microsoft dns with dns express. Thanks again.
    • Kevin_Davies_40's avatar
      Kevin_Davies_40
      Icon for Nacreous rankNacreous
      Jun 23, 2014
      Yes it will. As long as you have told DNS express to secondary those domains then it will answer for them. Don't get wide-ip mixed up with DNS express. Wide-IP configuration will always take precedence and it is configured in GTM, not in your DNS. How it works is simple. GTM will see if a FQDN matches an incoming request in Wide-IP. If not then it will check if the domain has been hosted in DNS express. If not then it will continues to check about five other name resolution configurations it can support to resolve the address. So essentially it falls through to each one if the previous does not provide resolution. The top of that list is Wide-IP.
  • Brian_T_246032's avatar
    Brian_T_246032
    Icon for Nimbostratus rankNimbostratus
    Jan 25, 2016

    hi Richard,

     

    I'm trying to set up a Windows DNS as a primary DNS server, and the F5 will be the secondary. Do you have a document on how it can be done?

     

    Thank you

     

    Brian