@page2012 Hi,
Thank you for posting in Q&A!
In order to provide you more specificed suggestions, firstly allow me to confirm the following information:
1.According to your description, when the client trying to communicate with one specific DC in the same site with client, the DNS queries failed, and a random DC located in a remote site responced. If my understanding has any problem, please correct it at any time.
If it is the situation, first I suggest you to check the configuration of your client's site and the DC of it. If there're some problem with this site or the DC, it will end up with contacting another random DC.
2.This DNS query packet was caught under what condition?
Hope you have a nice day : )
Gloria
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