On Thu, 2011-04-07 at 16:43 -0700, Joseph Tam wrote:
Dovecot seems to transfer group permissions of the mailbox to its corresponding cache. If it can't set group ownership, you get the fatal error message above. If the original mailbox is mode 0600, dovecot is smart enough not to set group ownership.
I couldn't find this information: shouldn't it be documented here?
Well, I don't know if documenting it there would actually help many people. Users having this problem aren't trying to share mailboxes, so they probably wouldn't be looking into that page. This is anyway mbox-specific problem, so I added it now to mbox page: http://wiki2.dovecot.org/MailLocation/mbox
Would it be useful to make this a configurable behaviour whereby a chgrp() failure of cache files will fall back to chown'ing to user=owner, mode=0600 instead? Or just leave the user to scratch their head?
I think it's safer to let user to scratch their head than to automatically go change permissions in a way that might make things worse.
I guess what I could do is add a wiki link to that error message explaining it. How about this now:
imap(tss): Error: fchown(/home/tss/mail/.imap/INBOX/dovecot.index.log.newlock, group=8(mail)) failed: Operation not permitted (egid=1000(tss), group based on /var/mail/tss - see http://wiki2.dovecot.org/Errors/NoPerm)