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_NAME_3's avatar
_NAME_3
Icon for Nimbostratus rankNimbostratus
Oct 02, 2013

GTM using WideIP along with DNS zone transfers to ISP

We are testing using Wide IP for load balancing and health checks for a mobile application. We believe we have everything configured correctly and load balancing and failover were working as expected. I setup my mobile device to monitor / test the setup and a few days later I got an error stating it was unable to connect. Everything looked ok on the GTM and the error went away on my phone by itself. It seems to be intermittent working most of the time, which is making it hard to troubleshoot.

 

After some more digging I found we are doing DNS zone transfers to our ISP's DNS servers which potentially could be answering DNS queries. Based on what I have read about the GTM and Wide IP setup this maybe part of the problem I am trying to solve and or cause more problems down the road.

 

Suggestions?

 

application delivery
BIG-IP DNS
gtm
wide ip

2 Replies

  • David__Pasch's avatar
    David__Pasch
    Icon for Altostratus rankAltostratus
    Oct 02, 2013

    Hard to understand your actual issue. Can you provide more detail? Explain the name resolution flow for a mobile device hitting your domain? Where is SOA for your records? Can you tell what kind of record you are getting when it fails OR are you not getting a response? Is it a public record anyone can access?

     

    Let us know!

     

  • _NAME_3's avatar
    _NAME_3
    Icon for Nimbostratus rankNimbostratus
    Oct 03, 2013

    The first part of the test is ActiveSync traffic for mail on mobile devices. The F5 box is providing the external DNS services and the wide IP setup for load balancing / availability. We are also doing a Zone Transfer to our ISP as a backup external DNS server. Public records and our F5 is the SOA. Its my understanding that either our DNS Server or the ISP's DNS server can respond to queries and my thought is that if the ISP DNS responds that the Wide IP would not work correctly?

     

    Once we had things configured my mobile device was able to connect and send / receive mail. Several days later I got a "Cannot Get Mail, The connections to the server failed" my assumption is no response. I am looking for an App for iPhone that maybe able to help figure out the connection problem from the phone side next time it can not connect.

     

    Hopefully this helps, im new to this.