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GrazianoSommariva's avatar
GrazianoSommariva
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May 27, 2026

F5 gtm last resort pool DNS Record problem

Hello, Big Ip v 17.1.X   I've found that when there is a GTM last Resort DNS Respone, and the DNS clients asks to a Microsoft DNS Server, Microsoft DNS server gives a NXDOMAIN response ( once ever...
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mwolf's avatar
mwolf
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Aug 14, 2026

What is the configuration of the DNS pool? There are situations when the DNS request can "fall" out of BIG-IP DNS and get an answer from BIND. The root cause of the NXDOMAIN may be caused by what BIND returns. I recommend configuring a fallback IP in the DNS pool to prevent the request being answered by BIND.