Shared mailboxes, index files and 'per-user-seen' flags

[Thomas Robers]

Hello,

i have a dovecot server version 2.3.1 under CentOS 6.9 and we're
using shared mailboxes with index files shared. With this configuration
I can see a lot of error messages like:

    Jun  6 13:20:31 mail dovecot: Error: imap(userA at tutech.de)<4513>
    <onjjWPdtDuLAqG3R>: /export/home/imap/userA at tutech.de/shared
    /userB at tutech.de/folder/dovecot.index.pvt view is inconsistent

In 10-mail.conf the location setting is:

    location = maildir:%%h/Maildir:INDEXPVT=%h/shared/%%u

I thought setting the index files to "not shared" might help to
get rid of the errors, so I changed the setting to:

    location = maildir:%%h/Maildir:INDEX=%h/shared/%%u:INDEXPVT=%h
    /shared/%%u

like it's mentioned in the Dovecot wiki. But that doesn't work as
I expected, because the 'per-user-seen' flags do not work correctly
anymore, i think. If UserA, who has UserB as shared mailbox,
changes the seen flags of UserBs INBOX, UserBs seen flags are also
changed. The other way, if UserB changes seen flags in his INBOX
they are not changed in the shared view of UserA. Is this the
supposed way to work  or do i have an error in the configuration?

Any help is appreciated.

Thanks, Thomas.

Here's my currently used configuration:

# 2.3.1 (c5a5c0c82): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.5.devel (61b47828)
# OS: Linux 2.6.32-696.23.1.el6.x86_64 x86_64 CentOS release 6.9 (Final) 
ext4
# Hostname: mail.tutech.de
auth_master_user_separator = *
auth_mechanisms = plain login
auth_verbose = yes
disable_plaintext_auth = no
doveadm_password =  # hidden, use -P to show it
doveadm_port = 12345
imap_max_line_length = 2 M
mail_debug = yes
mail_location = maildir:/export/home/imap/%Lu/Maildir
mail_plugins = acl zlib mail_log notify
mail_prefetch_count = 1
mailbox_idle_check_interval = 10 secs
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 mime foreverypart extracttext
namespace {
   hidden = no
   ignore_on_failure = no
   inbox = no
   list = children
   location = maildir:%%h/Maildir:INDEXPVT=%h/shared/%%u
   prefix = shared/%%u/
   separator = /
   subscriptions = yes
   type = shared
}
namespace inbox {
   hidden = no
   inbox = yes
   list = yes
   location =
   mailbox Drafts {
     special_use = \Drafts
   }
   mailbox Junk {
     special_use = \Junk
   }
   mailbox Sent {
     special_use = \Sent
   }
   mailbox "Sent Messages" {
     special_use = \Sent
   }
   mailbox Trash {
     special_use = \Trash
   }
   prefix = INBOX/
   separator = /
   type = private
}

passdb {
   args = /etc/dovecot/master-users
   driver = passwd-file
   master = yes
}
passdb {
   args = /etc/dovecot/dovecot-ldap.conf.ext
   driver = ldap
}
plugin {
   acl = vfile:/etc/dovecot/global-acls:cache_secs=300
   acl_shared_dict = file:/export/home/shared-db/shared-mailboxes
   mail_log_events = append delete undelete expunge copy mailbox_delete 
mailbox_rename flag_change
   mail_log_fields = uid box msgid size from flags
   mail_replica = tcp:mail2.tutech.de
   sieve = ~/.dovecot.sieve
   sieve_dir = ~/sieve
   sieve_global = /var/lib/dovecot/sieve/global/
   sieve_user_log = ~/.dovecot.sieve.log
   zlib_save = gz
   zlib_save_level = 6
}
protocols = imap pop3 lmtp sieve sieve
service aggregator {
   fifo_listener replication-notify-fifo {
     mode = 0666
     user = vmail
   }
   unix_listener replication-notify {
     mode = 0666
     user = vmail
   }
}
service auth {
   unix_listener /var/spool/postfix/private/auth {
     mode = 0666
   }
   unix_listener auth-userdb {
     group = vmail
     mode = 0660
     user = vmail
   }
}
service config {
   unix_listener config {
     user = vmail
   }
}
service doveadm {
   inet_listener {
     port = 12345
   }
   user = vmail
}
service imap-login {
   inet_listener imaps {
     port = 993
     ssl = yes
   }
   process_limit = 500
   process_min_avail = 20
}
service imap {
   executable = imap
}
service lmtp {
   inet_listener lmtp {
     address = 127.0.0.1
     port = 24
   }
}
service managesieve-login {
   inet_listener sieve {
     port = 4190
   }
   inet_listener sieve_deprecated {
     port = 2000
   }
}
service pop3-login {
   inet_listener pop3s {
     port = 995
     ssl = yes
   }
}
service pop3 {
   executable = pop3
}
service replicator {
   unix_listener replicator-doveadm {
     mode = 0666
   }
}
ssl = required
ssl_cert = </etc/pki/dovecot/certs/mail.tutech.de.crt_chain
ssl_cipher_list = ALL:!LOW:!SSLv2:!EXP:!aNULL:!EXPORT
ssl_dh =  # hidden, use -P to show it
ssl_key =  # hidden, use -P to show it
syslog_facility = local6
userdb {
   args = /etc/dovecot/dovecot-ldap-userdb.conf.ext
   driver = ldap
}
protocol lmtp {
   mail_plugins = acl zlib mail_log notify sieve
}
protocol imap {
   mail_max_userip_connections = 100
   mail_plugins = acl zlib mail_log notify imap_zlib imap_acl
   rawlog_dir = /tmp/rawlog/%u
}