Questions on supporting Shared Mailboxes using imapc://

[Nathan Coulson]

I was not able to get a shared mailbox setup working using imapc. Tested 
using mailboxes on the same server, as well as other servers.

We are using dovecot 2.2.10 from Centos 7, following the guide at 
http://wiki2.dovecot.org/SharedMailboxes/ClusterSetup


imapc_host=192.168.5.5 #(Local dovecot server)
imapc_master_user= %u
imapc_password=TempPass
#imapc_user=te...@example.com # Added for testing.
namespace {
  type = shared
  separator = /
  prefix = shared/%%u/
  list = children
  location = imapc:~/shared/%%u/
}
namespace { # used as a control to verify that shared mailboxes work
  type = shared
  separator = /
  prefix = shared2/%%u/
  list = children
  location = sdbox:%%h:INDEXPVT=~/shared2/%%u
}


dict {
  acl = mysql:/etc/dovecot/dovecot-sql_aggelos_shares.conf.ext
}

plugin {
  acl = vfile
  acl_shared_dict = proxy::acl
}

mail_plugins = acl

protocol imap {
  mail_plugins = acl imap_acl
}

passdb {
  driver = sql
  args = /etc/dovecot/dovecot-sql.conf.ext
}


passdb { # for master user logins
  driver = sql
  args = /etc/dovecot/dovecot-sql_aggelos_aclmaster.conf.ext
  master = yes
  pass = yes
}

userdb {
  driver = sql
  args = /etc/dovecot/dovecot-sql.conf.ext
}





I can login using te...@example.com*t...@example.com (and see all of 
test2's email), and it looks like it authenticates ok via imap, but 
shared never shows up.  No issues using shared2 which uses direct access 
to the mailbox


doveadm acl debug -u t...@example.com shared/te...@example.com (Fails, 
uses imapc)

doveadm(t...@example.com): Info: Mailbox 'INBOX' is in namespace 
'shared/te...@example.com/'
doveadm(t...@example.com): Info: Mailbox path: 
/misc/1/2/mail/t...@example.com-4/shared/te...@example.com/.INBOX
doveadm(t...@example.com): Info: All message flags are shared across 
users in mailbox
doveadm(t...@example.com): Info: User t...@example.com has no rights for 
mailbox
doveadm(t...@example.com): Error: User t...@example.com is missing 
'lookup' right
doveadm(t...@example.com): Info: Mailbox shared/te...@example.com is NOT 
visible in LIST



doveadm acl debug -u t...@example.com shared/te...@example.com/Junk 
(Fails, contains a folder that exists)
doveadm(t...@example.com): Info: Mailbox 'Junk' is in namespace 
'shared/te...@example.com/'
doveadm(t...@example.com): Info: Mailbox path: 
/misc/1/2/mail/t...@example.com-4/shared/te...@example.com/.Junk
doveadm(t...@example.com): Info: All message flags are shared across 
users in mailbox
doveadm(t...@example.com): Info: User t...@example.com has no rights for 
mailbox
doveadm(t...@example.com): Error: User t...@example.com is missing 
'lookup' right
doveadm(t...@example.com): Info: Mailbox shared/te...@example.com/Junk 
is NOT visible in LIST


doveadm acl debug -u t...@example.com shared/te...@example.com/z (Fails, 
 contains a folder that does not exist.  Expected result)

doveadm(t...@example.com): Error: Mailbox 'z' in namespace 
'shared/te...@example.com/' doesn't exist in 
/misc/1/2/mail/t...@example.com-4/shared/te...@example.com/.z



doveadm acl debug -u t...@example.com shared2/te...@example.com (Works, 
using direct storage)

doveadm(t...@example.com): Info: Mailbox 'INBOX' is in namespace 
'shared2/te...@example.com/'
doveadm(t...@example.com): Info: Mailbox path: 
/misc/1/2/mail/te...@example.com-87/mailboxes/INBOX/dbox-Mails
doveadm(t...@example.com): Info: Per-user private flags in mailbox: \Seen
doveadm(t...@example.com): Info: User t...@example.com has rights: 
lookup read write-seen
doveadm(t...@example.com): Info: Mailbox found from dovecot-acl-list
doveadm(t...@example.com): Info: User te...@example.com found from ACL 
shared dict
doveadm(t...@example.com): Info: Mailbox shared2/te...@example.com is 
visible in LIST



It feels like the acl information in the vfiles is not available when 
using imapc.



Our setup is as follows: (Currently does not use Dovecot Director, but 
has the same issues where shared mailboxes may not be local on the server)
* Front servers, that are running dovecot (proxy to backend servers)
* Backend Servers, each handle their own local users.


Thank you

--
Nathan Coulson
System Administrator for Bravenet
www.bravenet.com
nat...@bravenet.com