Dear Dovecot users, hello. I will merge two issues I have into a single email because they may be related.
I used dovecot on a OmniOS server since 2014 (currently OmniOS r151014) with the following configuration (it shows 2.2.18 because I recently updated dovecot, skipping only the PostgreSQL plugin):
# 2.2.18: /etc/dovecot/dovecot.conf # OS: SunOS 5.11 i86pc zfs mail_location = maildir:/tank/home/%u/Maildir mail_privileged_group = mail namespace inbox { inbox = 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 = } passdb { driver = pam } protocols = imap ssl = required ssl_cert = </etc/dovecot/certs/dovecot.pem ssl_key = </etc/dovecot/private/dovecot.pem userdb { driver = passwd }
You can see that I set the Maildir folder inside the shared home folders of my server (it is only one user, anyway). It always worked perfectly, but one-two months ago I changed the permissions of my whole home folder, recursively, to add proper ACLs. I needed them because the clients started using illumos kernel SMB (relying on ACLs) instead of Netatalk/AFP (relying on Unix perms only). I didn't realise I applied the ACLs also to the Maildir folder.
Dovecot worked for several weeks fine, I noticed the issue only yesterday when a mailbox (see below) appeared in Thunderbird completely empty even if the "cur" subfolder on the server still contains all the mails.
Dovecot was throwing some errors like:
dovecot: [ID 583609 mail.error] imap(olaf): Error: rename(/tank/home/olaf/Maildir/.&A6k- Mailing Lists.Log/dovecot.index.cache) failed: Permission denied (euid=501(olaf) egid=501(olaf) UNIX perms appear ok (ACL/MAC wrong?)) dovecot: [ID 583609 mail.error] imap(olaf): Error: rename(/tank/home/olaf/Maildir/.&A6k- Mailing Lists.Log/dovecot.index.tmp, /tank/home/olaf/Maildir/.&A6k- Mailing Lists.Log/dovecot.index) failed: Permission denied dovecot: [ID 583609 mail.error] imap(olaf): Error: unlink(/tank/home/olaf/Maildir/subscriptions.lock) failed: Permission denied dovecot: [ID 583609 mail.error] imap(olaf): Error: rename(/tank/home/olaf/Maildir/subscriptions.lock, /tank/home/olaf/Maildir/subscriptions) failed: Permission denied
I will post here the current permissions of the folder containing Maildir, of the Maildir itself, of its contents, and of the folder that appears empty when browsed with a client (Thunderbird).
/tank/home/olaf $ ls -lV .. drwx------+ 16 olaf olaf 17 Sep 19 01:52 olaf user:olaf:rwxpdDaARWcCos:fd-----:allow group:2147483648:rwxpdDaARWcCos:fd-----:allow everyone@:rwxpdDaARWcCos:fd-----:deny
/tank/home/olaf $ ls -lV drwxrwx--- 348 olaf olaf 359 Sep 19 01:51 Maildir owner@:rwxp--aARWcCos:-------:allow group@:rwxp--a-R-c--s:-------:allow everyone@:------a-R-c--s:-------:allow
/tank/home/olaf $ ls -lV Maildir/ drwxrwx--- 2 olaf olaf 2 Jan 30 2014 cur owner@:rwxp--aARWcCos:-------:allow group@:rwxp--a-R-c--s:-------:allow everyone@:------a-R-c--s:-------:allow -rwxrwx--- 1 olaf olaf 21 Jan 30 2014 dovecot-keywords owner@:rwxp--aARWcCos:-------:allow group@:rwxp--a-R-c--s:-------:allow everyone@:------a-R-c--s:-------:allow (ALL THE SAME PERMISSIONS FOR THE OTHER FILES EXCEPT...) -rwxrwx--- 1 olaf olaf 13735 Jan 24 2015 subscriptions owner@:rwxp--aARWcCos:-------:allow group@:rwxp--a-R-c--s:-------:allow everyone@:------a-R-c--s:-------:allow -rw-rw---- 1 olaf olaf 13709 Sep 19 01:51 subscriptions.lock owner@:rw-p--aARWcCos:-------:allow group@:rw-p--a-R-c--s:-------:allow everyone@:------a-R-c--s:-------:allow
The folder that appears empty:
/tank/home/olaf $ ls -lV Maildir/.Generiche/ total 513 drwxrwx--- 2 olaf olaf 949 Sep 18 01:42 cur owner@:rwxp--aARWcCos:-------:allow group@:rwxp--a-R-c--s:-------:allow everyone@:------a-R-c--s:-------:allow -rwxrwx--- 1 olaf olaf 46 May 18 2014 dovecot-keywords owner@:rwxp--aARWcCos:-------:allow group@:rwxp--a-R-c--s:-------:allow everyone@:------a-R-c--s:-------:allow (ALL THE SAME PERMISSIONS FOR THE OTHER FILES)
I really hope you will have the time to help me because I already applied the permissions recursively and I removed the ACLs, almost as it was before my mistake. I specified "almost" because originally (I checked the backups) the Maildir folder had an ACL that gave access permissions also to the group "mail":
drwxrwx---+349 olaf olaf 359 Feb 16 2014 Maildir group:mail:rwxpdDaARWcCos:fd-----:allow owner@:rwxpdDaARWcCos:fd----I:allow group@:rwxpdDaARWcCos:fd----I:allow everyone@:rwxpdDaARWcCos:fd----I:deny
Yesterday I haven't replicated it because from the documentation I understood it was not necessary.
My questions, in short:
- what are the permissions I need to give to the Maildir folder? I understood from the documentation it's 700, with my user/group (the one of the user accessing the mail). What about ACLs? and what about group "mail"?
- the (only!) subfolder which appears empty in Thunderbird, may it depend on the permissions? maybe due to them the index was not updated and UIDs don't match. If after applying the correct permissions I still cannot see its contents, is there a way to recover the mails? the files are all still there.
Sorry for the long email, but after several tries yesterday I exhausted my ideas.
Regards, Olaf