Just setup a new server on the weekend with Ubuntu 8.10 beta, and Dovecot 1.1.4. Every now and then, the IMAP server dies, and won't let users authenticate. It happens about once or twice a day. In /var/log/mail.log, you can see dovecot complaining about critial errors:
Oct 21 14:46:16 tachikoma dovecot: imap-login: Login: user=<jason>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, TLS Oct 21 14:46:16 tachikoma dovecot: IMAP(jason): Disconnected: Logged out bytes=769/9124 Oct 21 14:47:15 tachikoma dovecot: auth-worker(default): pam(jason,127.0.0.1): pam_start() failed: Critical error - immediate abort Oct 21 14:47:17 tachikoma dovecot: imap-login: Disconnected (auth failed, 1 attempts): user=<jason>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, TLS
If I have a look at /var/log/auth.log, I see:
Oct 21 14:47:15 tachikoma dovecot-auth: PAM _pam_init_handlers: error reading /etc/pam.d/dovecot Oct 21 14:47:15 tachikoma dovecot-auth: PAM _pam_init_handlers: [Critical error - immediate abort] Oct 21 14:47:15 tachikoma dovecot-auth: PAM error reading PAM configuration file Oct 21 14:47:15 tachikoma dovecot-auth: PAM pam_start: failed to initialize handlers
This sounds ominous. If I try to cat /etc/pam.d/dovecot, though, the file is obviously there:
jason@tachikoma:/var/log$ cat /etc/pam.d/dovecot #%PAM-1.0 @include common-auth @include common-account @include common-session
And restarting dovecot seems to fix the problem. Dovecot WAS running just fine, servicing mail all day long, and then suddenly it won't read the PAM config file, and then it won't let anyone log in until I log in and kill it. Any ideas?
My IMAP client is either Thunderbird or Roundcube, if that's relevant.