I came in today with full queues on all my backend servers and bridgehead. Additional information on the queues said something like “could not bind to destination server”, then something about DNS. Turns out the Primary DNS server was down. We brought the Primary DNS server back up and the queues started emptying. What I don’t understand is why didn’t the Secondary DNS server take over?
It was resopnding to Ping, but no mail flow. I did reconfigure one of the servers and made the Secondary DNS the Primary on that server. That worked for that server. But still, why didn’t it just fail over to the configured Secondary DNS? Any ideas on how I can even troubleshoot this? Thanks.
