[Dovecot] New admin, not much success

[William Blunn]

Chuck McManis wrote:
> On Wed, Jun 16, 2010 at 8:44 AM, William Blunn
> <bill+dovecot at blunn.org<bill%2Bdovecot at blunn.org>
>   
>> wrote:
>>     
>
>   
>> Timo Sirainen wrote:
>>
>>     
>>> On Wed, 2010-06-16 at 08:28 -0700, Chuck McManis wrote:
>>>
>>>
>>>       
>>>> Jun 16 08:22:07 eeebox dovecot: pop3(cmcmanis): Error: user cmcmanis:
>>>> Initialization failed: Initializing mail storage from mail_location
>>>> setting
>>>> failed: mbox: mbox root directory can't be a file: /home/cmcmanis/Mailbox
>>>> (
>>>> http://wiki.dovecot.org/MailLocation/Mbox)
>>>>
>>>>         
>>> ..
>>>
>>>
>>>
>>>       
>>>> Now it strikes me that this message indicates that Dovecot is confused
>>>> about
>>>> how mail is delivered on my system and is looking for a Maildir
>>>> implementation when I"m using single files.
>>>>
>>>>
>>>>         
>>> No, it's looking for a directory containing mbox files. See the wiki URL
>>> and "Only /var/mail/ mboxes" section in it.
>>>
>>>       
>> One wonders if Chuck's stated requirement may be reasonably served by
>> something like this:
>>
>> mail_location = mbox:~/mail:INBOX=~/Mailbox
>>
>> and create a directory "mail" in each user's home directory.
>>
>> This should then make Dovecot consider each user's INBOX to be an
>> mbox-format file at "~/Mailbox", and also allows Dovecot to keep 
>> indexes in
>> the directory "~/mail", thereby enabling Chuck's users to take 
>> advantage of
>> Dovecot's indexing functionality.
>>
> Fascinating, that gets it further, it creates a bunch of stuff in 
> mail/.imap (which is confusing because I really really don't want IMAP 
> and have removed IMAP from the protocols served and the ports listened 
> on etc)
> Then it complains that it can't do an fcntl on Mailbox. It said 
> 'operation not supported.'

Strange. Perhaps there is a problem locking the mbox file using fcntl. 
Though I would be surprised if this were the case on a modern filesystem 
on a modern unix-like OS.

If you can't use fcntl then you may be limited to using dotlocks (see 
http://wiki.dovecot.org/MboxLocking), though you would also need to 
determine with certainty that your MTA was using a compatible locking 
strategy --- don't skip this step unless you want to be spending 105% of 
your time firefighting weekly trouble reports of users complaining that 
their mailboxes are scrambled.

Though, if getting reliable locking on mbox is proving expensive, you 
might find your overall cheapest solution is to switch to Maildir. With 
mbox you have to be careful and work hard to make sure your various 
software components cooperate on mailbox locking and even silly things 
like mbox format variants (does it escape "From" or not?), and it is 
almost impossible to be certain that both the MTA and POP3 system are 
going to cooperate perfectly and not scramble mailboxes occasionally. 
With Maildir, everything works out-of-the-box with no configuration 
without breaking a sweat; mailbox corruption is simply designed-out.

Bill