I periodically get notice in my Zimbra section about unavailable IMAP service like this:
So, I trying to connect
External IMAP Check
OK 05-21-2010 15:18:00 0d 1h 23m 35s 1/4 IMAP OK - 0.101 second response time on port 143 [* OK mydomain Zimbra IMAP4rev1 service ready]
and I get the response after 20-25 sec.
telnet myserver 143
BTW the same situation with internal IMAP check and it happens not more than 2-3 times per week. It goes on about 20-30 minutes. And I didn't see any alerting in my mailbox.log.
Thank in advance.