[Dovecot] Ring SYNC appears to have got lost, resending after upgrade

[Patrick Westenberg]

Hi @all,

on Saturday I upgraded two dovecot servers from squeeze to wheezy and
dovecot from 2.1.x to 2.2.5 (compiled from sources). After the upgrade
everything worked fine at first.

On Sunday Morning I recognized these errors (they occured after a reload 
for logging purpose on midnight) on one server:

director: Error: Ring SYNC appears to have got lost, resending

After reloading/restarting both dovecot services the error occured on
both servers. After some research I deleted some "zlib"-File which
isn't needed anymore in dovecot 2.2.x and reinstalled dovecot. The
error message disappeared.

Today the error occured again (after the reload on midnight) and again
on one node only until reloading/restarting the other node too.
However, there is an additional error message:

Sep 09 10:27:07 director: Error: Ring SYNC appears to have got lost, 
resending
Sep 09 10:27:10 director: Panic: file login-connection.c: line 88 
(login_host_callback): assertion failed: (strncmp(request->line, "OK\t", 
3) == 0)


Any ideas?

Patrick




node1:
# 2.2.5: /usr/local/etc/dovecot/dovecot.conf
# OS: Linux 3.2.0-4-amd64 x86_64 Debian 7.1
auth_mechanisms = plain login
director_mail_servers = 172.17.1.2 172.17.1.1
director_servers = 172.17.1.3 172.17.1.4
director_user_expire = 5 mins
lmtp_proxy = yes
log_path = /var/log/dovecot.log
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope 
encoded-character vacation subaddress comparator-i;ascii-numeric 
relational regex imap4flags copy include variables body enotify 
environment mailbox date ihave
protocols = imap pop3 lmtp sieve
service auth {
   unix_listener /var/spool/postfix/private/auth {
     group = postfix
     mode = 0666
     user = postfix
   }
   unix_listener auth-userdb {
     user = dovecot
   }
}
service director {
   fifo_listener login/proxy-notify {
     mode = 0666
   }
   inet_listener {
     address = 172.17.1.3
     port = 9090
   }
   unix_listener director-userdb {
     mode = 0600
   }
   unix_listener login/director {
     mode = 0666
   }
}
service imap-login {
   executable = imap-login director
}
service lmtp {
   inet_listener lmtp {
     address = 172.17.1.3
     port = 24
   }
}
service managesieve-login {
   executable = managesieve-login director
   inet_listener sieve {
     port = 4190
   }
}
service pop3-login {
   executable = pop3-login director
}
ssl_cert = </etc/ssl/certs/wildcard.xxx.crt
ssl_key = </etc/ssl/private/wildcard.xxx.key
protocol !smtp {
   passdb {
     args = proxy=y nopassword=y starttls=any-cert
     driver = static
   }
}
protocol smtp {
   passdb {
     args = /usr/local/etc/dovecot/dovecot-sql.conf.ext
     driver = sql
   }
   userdb {
     args = /usr/local/etc/dovecot/dovecot-sql.conf.ext
     driver = sql
   }
}
protocol lmtp {
   auth_socket_path = director-userdb
}


node2:
# 2.2.5: /usr/local/etc/dovecot/dovecot.conf
# OS: Linux 3.2.0-4-amd64 x86_64 Debian 7.1
auth_mechanisms = plain login
director_mail_servers = 172.17.1.2 172.17.1.1
director_servers = 172.17.1.4 172.17.1.3
director_user_expire = 5 mins
lmtp_proxy = yes
log_path = /var/log/dovecot.log
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope 
encoded-character vacation subaddress comparator-i;ascii-numeric 
relational regex imap4flags copy include variables body enotify 
environment mailbox date ihave
protocols = imap pop3 lmtp sieve
service auth {
   unix_listener /var/spool/postfix/private/auth {
     group = postfix
     mode = 0666
     user = postfix
   }
   unix_listener auth-userdb {
     user = dovecot
   }
}
service director {
   fifo_listener login/proxy-notify {
     mode = 0666
   }
   inet_listener {
     address = 172.17.1.4
     port = 9090
   }
   unix_listener director-userdb {
     mode = 0600
   }
   unix_listener login/director {
     mode = 0666
   }
}
service imap-login {
   executable = imap-login director
   process_min_avail = 2
   service_count = 0
   vsz_limit = 128 M
}
service lmtp {
   inet_listener lmtp {
     address = 172.17.1.4
     port = 24
   }
}
service managesieve-login {
   executable = managesieve-login director
   inet_listener sieve {
     port = 4190
   }
}
service pop3-login {
   executable = pop3-login director
}
ssl_cert = </etc/ssl/certs/wildcard.xxx.crt
ssl_key = </etc/ssl/private/wildcard.xxx.key
protocol !smtp {
   passdb {
     args = proxy=y nopassword=y starttls=any-cert
     driver = static
   }
}
protocol smtp {
   passdb {
     args = /usr/local/etc/dovecot/dovecot-sql.conf.ext
     driver = sql
   }
   userdb {
     args = /usr/local/etc/dovecot/dovecot-sql.conf.ext
     driver = sql
   }
}
protocol lmtp {
   auth_socket_path = director-userdb
}