Hi, >> I'm also pretty sure it's not a network issue. After passing >> billions of packets there isn't a single error. I'm also pretty sure >> DNS is configured properly. > > Have you checked the connection between postfix and the exchange > machines? After some years, a cable can get bad, lousy, and the > packets would not pass so reliably anymore. After moving a > machine/wandering around a rack cabinet, one may have step on a cable > and disconnect it or damage it.
I had them replace the network cable, to no avail. How can I add some additional debugging, without overwhelming the system, to troubleshoot this further? Is there a way to increase the debugging info for messages in the queue, such as the last time an attempt was made to deliver the message, or the timeline of what was happening during the failed delivery attempt? Thanks, Alex
