dsync replication issues with shared mailboxes

[Sergey Schwartz]

Gentlemen,

I've setup 2 servers with dsync replication and hit a serious issue - 
some messages got duplicated thousands times in some shared mailboxes(~5).
There is actually no reason to replicate anything from shared name space 
and I've tried to limit replication scope with just 'inbox' name space 
but it didn't help.

dovecot version ||2.2.18 (2de3c7248922)

errors in the logs

May 26 13:23:38 mx10 dovecot: doveadm: Error: 
dsync-remote(korobova at mydomain): Error: Mailbox turkey: Save commit 
failed: Message has been copied too many times (24498 + 8270)
May 26 13:25:16 mx10 dovecot: doveadm: Error: 
dsync-remote(korobova at mydomain): Error: Mailbox turkey: Save commit 
failed: Message has been copied too many times (24498 + 8270)
May 26 13:26:40 mx10 dovecot: dsync-local(zhelonkina at mydomain): Error: 
Mailbox booking: Save commit failed: Message has been copied too many 
times (0 + 32768)
May 26 13:30:01 mx10 dovecot: dsync-local(kashchits at mydomain): Error: 
Mailbox shared/davydjanc at mydomain/russia: Save commit failed: Message 
has been copied too many times (17139 + 15629)
May 26 13:30:01 mx10 dovecot: dsync-local(davydjanc at mydomain): Error: 
Mailbox russia: Save commit failed: Message has been copied too many 
times (17139 + 15629)
May 26 13:30:01 mx10 dovecot: dsync-local(kapitanova at mydomain): Error: 
Mailbox shared/davydjanc at mydomain/russia: Save commit failed: Message 
has been copied too many times (17139 + 15629)
May 26 13:30:03 mx10 dovecot: dsync-local(grinenko at mydomain): Error: 
Mailbox shared/davydjanc at mydomain/russia: Save commit failed: Message 
has been copied too many times (17139 + 15629)
May 26 13:30:03 mx10 dovecot: dsync-local(maslova at mydomain): Error: 
Mailbox shared/davydjanc at mydomain/russia: Save commit failed: Message 
has been copied too many times (17139 + 15629)

Data was not lost and I've been able to run deduplicate for most of 
mailboxes, but one mailbox got broken and I had to manually move message 
to another mailbox

force-resync failed fot that mailbox
doveadm(l.davydjanc at mydomain): Error: mdbox map 
/srv/vmail/current/mydomain/davydjanc/storage/dovecot.map.index 
corrupted: map_uid=361735 refcount too low


Hope you guys have an idea how to work it around :)



replication.conf

dsync_remote_cmd = /usr/bin/ssh -i /home/vmail/.ssh/id_rsa -l %{login} 
%{host} doveadm dsync-server -u %u

service aggregator {
     fifo_listener replication-notify-fifo {
         user = vmail
         mode = 0600
     }
     unix_listener replication-notify {
         user = vmail
         mode = 0600
         }

     process_min_avail = 1
}

service replicator {
     unix_listener replicator-doveadm {
         user = vmail
         mode = 0600
     }
     process_min_avail = 1
}

service doveadm {
     user = vmail
     process_min_avail = 1
}

service config {
     unix_listener config {
         user = vmail
     }
     process_min_avail = 1
}

replication_max_conns = 50
replication_dsync_parameters = -d -n inbox -l 30 -U

plugin {
     mail_replica = remote:vmail at mx20
}



doveconf -n

# 2.2.18 (2de3c7248922): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.4.8
# OS: Linux 3.13.0-34-generic x86_64 Ubuntu 14.04.2 LTS xfs
auth_cache_negative_ttl = 0
auth_cache_size = 512 M
auth_default_realm = mydomain
auth_failure_delay = 5 secs
auth_worker_max_count = 4096
default_client_limit = 40960
default_process_limit = 8192
default_vsz_limit = 2 G
disable_plaintext_auth = no
first_valid_gid = 500
mail_location = mdbox:/srv/vmail/current/%d/%n
mail_plugins = acl zlib notify replication
mail_shared_explicit_inbox = yes
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 index ihave duplicate
mdbox_rotate_size = 32 M
namespace {
   list = yes
   location = mdbox:/srv/vmail/current/%%d/%%n
   prefix = shared/%%u/
   separator = /
   subscriptions = no
   type = shared
}
namespace inbox {
   inbox = yes
   location =
   mailbox Drafts {
     auto = subscribe
     special_use = \Drafts
   }
   mailbox Junk {
     auto = subscribe
     special_use = \Junk
   }
   mailbox Sent {
     auto = subscribe
     special_use = \Sent
   }
   mailbox Trash {
     auto = subscribe
     special_use = \Trash
   }
   prefix =
   separator = /
}
passdb {
   args = /etc/dovecot/virtual/base.conf.ext
   driver = sql
}
passdb {
   args = /etc/dovecot/virtual/master.conf.ext
   driver = sql
}
plugin {
   acl = vfile
   acl_shared_dict = 
file:/srv/vmail/current/shared.db/000-shared-mailboxes.db
   sieve = 
file:/srv/vmail/current/%d/%n/sieve;active=/srv/vmail/current/%d/%n/active.sieve
   sieve_max_redirects = 0
   zlib_save = xz
   zlib_save_level = 6
}
protocols = " imap lmtp sieve"
service auth {
   unix_listener /var/spool/postfix/private/auth {
     group = postfix
     mode = 0666
     user = postfix
   }
}
service imap-login {
   process_min_avail = 24
}
service imap {
   process_limit = 4096
}
service lmtp {
   unix_listener /var/spool/postfix/private/dovecot-lmtp {
     group = postfix
     mode = 0600
     user = postfix
   }
}
ssl_cert = </etc/ssl/mxbgcom/2015/mydomain.com.crt.chained
ssl_key = </etc/ssl/mxbgcom/2015/mydomain.com.key
syslog_facility = local0
userdb {
   args = /etc/dovecot/virtual/base.conf.ext
   driver = sql
}
protocol lmtp {
   mail_plugins = acl zlib notify replication sieve
}
protocol imap {
   mail_max_userip_connections = 15
   mail_plugins = acl zlib notify replication imap_acl
}



-- 
Best regards,
Sergey Schwartz

Senior System Administrator
Biblio Globus Tour Operator
www.bgoperator.ru

T: +7 495 5042500 ext 1532
E: sergey.schwartz at bgoperator.com