[Dovecot] Server shutting down

[Simon B]

Hi

I recently moved to Debian Wheezy and installed dovecot from apt-get.
root at mail:~# dpkg -l | grep dovecot
ii  dovecot-common                     1:2.1.7-7
   all          Transitional package for dovecot
ii  dovecot-core                       1:2.1.7-7
   amd64        secure mail server that supports mbox, maildir, dbox
and mdbox mailboxes
ii  dovecot-gssapi                     1:2.1.7-7
   amd64        GSSAPI authentication support for Dovecot
ii  dovecot-imapd                      1:2.1.7-7
   amd64        secure IMAP server that supports mbox, maildir, dbox
and mdbox mailboxes
ii  dovecot-ldap                       1:2.1.7-7
   amd64        LDAP support for Dovecot
ii  dovecot-managesieved               1:2.1.7-7
   amd64        secure ManageSieve server for Dovecot
ii  dovecot-mysql                      1:2.1.7-7
   amd64        MySQL support for Dovecot
ii  dovecot-pgsql                      1:2.1.7-7
   amd64        PostgreSQL support for Dovecot
ii  dovecot-pop3d                      1:2.1.7-7
   amd64        secure POP3 server that supports mbox, maildir, dbox
and mdbox mailboxes
ii  dovecot-sieve                      1:2.1.7-7
   amd64        sieve filters support for Dovecot
ii  dovecot-sqlite                     1:2.1.7-7
   amd64        SQLite support for Dovecot

Having previously been on 1.2 on Debian Squeeze the upgrade went
flawlessly (and automatically, as I'd already placed the 1.2
dovecot.conf file before installing 2.1.7).  And I've been very happy.

However, yesterday the server just just shutdown.
/var/log/mail.log.1:42890:Jun 30 17:27:04 mail dovecot: imap: Server
shutting down. in=14 out=648
/var/log/mail.log.1:42891:Jun 30 17:27:04 mail dovecot: imap: Server
shutting down. in=14 out=648
/var/log/mail.log.1:42893:Jun 30 17:27:04 mail dovecot: imap: Server
shutting down. in=14 out=648
/var/log/mail.log.1:42895:Jun 30 17:27:34 mail dovecot: imap: Server
shutting down. in=739 out=2081
/var/log/mail.log.1:42896:Jun 30 17:27:34 mail dovecot: imap: Server
shutting down. in=1764 out=4027

There's no error|panic|warning|fatal messages in any of the logs.

root at mail:~# grep -in dovecot /var/log/syslog | grep
'(fatal|error|warning|panic)'
root at mail:~# grep -in dovecot /var/log/messages | grep
'(fatal|error|warning|panic)'
root at mail:~# grep -in dovecot /var/log/daemon.log | grep
'(fatal|error|warning|panic)'
root at mail:~# grep -inr dovecot /var/log/mail* | grep
'(fatal|error|warning|panic)'

Although everything should log to mail.log if I set up rsyslog properly.

The timestamp is not correlated to any of my cron jobs.

How can I find out what caused this?  Of course with Dovecot shut down
Postfix refused to send mail as there was no auth service available.

Simon