[Dovecot] Dsync error: Couldn't drop privileges: getgrnam

[Alan McGinlay - SICS]

On 2013-12-10 11:52, Alan McGinlay - SICS wrote:
> On 2013-12-10 11:34, Robert Schetterer wrote:
> Am 10.12.2013 11:25, schrieb Alan McGinlay - SICS:
> On 2013-12-09 11:21, Alan McGinlay - SICS wrote:
> On 2013-12-08 22:08, Alan McGinlay - SICS wrote:
> Actually I do, /var/vmail (contains virtual domain mailboxes) is
> owned by vmail:vmail
> 
> On 2013-12-08 21:49, Timo Sirainen wrote:
> On 5.12.2013, at 22.18, Alan McGinlay - SICS <alanm at sics.se> wrote:
> 
> mail_privileged_group = vmail
> ..
> mail_location = maildir:~/Maildir
> ..
> dsync(alantestuser at whatever.com): Error: user
> alantestuser at whatever.com: Couldn't drop privileges: getgrnam(vmail)
> failed: No such file or directory (in mail_privileged_group setting)
> 
> You don’t have vmail group in your system? Either create it or remove
> this setting. Most likely you want to remove it, since this setting
> was meant only for mbox format, while you’re using maildir.
> 
> After much trial and error and following Timos advice, I managed to
> get a sync to at least start and it lists folders, then it starts
> spamming this:
> 
> dsync(alantestuser at whatever.com): Error:
> safe_mkstemp(/tmp/dovecot.doveadm.) failed: No such file or directory
> dsync(alantestuser at whatever.com): Error:
> safe_mkstemp(/tmp/dovecot.doveadm.) failed: No such file or directory
> dsync(alantestuser at whatever.com): Error:
> safe_mkstemp(/tmp/dovecot.doveadm.) failed: No such file or directory
> ...
> 
> /tmp/dovecot.doveadm. does indeed not exist but I can't find any
> reference to it online or in the docs,
> 
> Any ideas?
> 
> 
> Still not able to get anywhere with this :( It really feels like a
> permissions problem, either with the master user, the unix user i 
> start
> the dsync with (root) or the user that dsync runs as (vmail). I tried
> looking at the code for safe_mkstemp but still couldn't work out the
> source of this problem. If anyone has an idea it would be great to 
> hear it!
> 
> perhaps check
> the dsync target directory must be writable by vmail:vmail
> 
> 
> Best Regards
> MfG Robert Schetterer
> 
> Thanks, vmail:vmail owns all mail and parent directories up to
> /var/vmail/. I tried changing mail_temp_dir in 10-mail.conf from /tmp/
> to /var/vmail/tmp (and i created that directory) but it made no
> difference apart from changing the directory in the "safe_mkstemp"
> error message. If I comment out mail_temp_dir then the error changes
> to:
> 
> dsync(alantestuser at whatever.com): Error:
> safe_mkstemp(/tmp/dovecot.doveadm.) failed: Permission denied
> dsync(alantestuser at whatever.com): Error:
> stat(/tmp/dovecot.doveadm.3c303c239d223495) failed: Permission denied

Interestingly, the synchronization actually does seem to work! I hadn't 
noticed at first but in spite of the error, mails are synced across and 
seemingly are completely intact!

It would be really good to find out the source of this error though!

/A