[IMail Forum] DNS problem

[Glenn Bullion]

I had a weird problem yesterday.  Majority of my outgoing mail just sat in the queue.  The log reported a boat load of stack connects, so a lot of my mail wasn't going out.  Not all of it, mind you, some did go out, but a lot hung in the queue.  I tried restarted services, the server, etc.  What I ended up doing was going into SMTP properties and changing the local DNS server to my secondary DNS server, then mail started going out.  What could happen to an internal DNS server that it would suddenly stop translating?  I made no changes at all.