[jefft@iri.columbia.edu]

The DNS server is external to our mail server, but we constantly monitor it (our DNS server) for reply times, and haven't seen anything excessive recently.

Disk space is plentiful.

I've attached my master.cf, but I think its the default zimbra release.

We don't have any transports. This server handles all mail, although we do have a front-end spam/virus gateway that delivers mail to Zimbra. But again, we monitor that machine for reply times, and it has been fine.

Since this is intermittent, I don't think its a 'Zimbra' problem per-se. The problem probably lies in that Zimbra [some process] is not connecting to a service or losing a socket connection after a timeout, but I'm not very good at debugging zimbra and wonder what flags I might turn on to increase log messaging to trace the actual problem.

Thanks again for your help.