[Dovecot] HA Dovecot Config?

[Eric Rostetter]

Quoting Rick Romero <rick at havokmon.com>:

>> See that last line there???  Want to bet something in the mail setup
>> (MTA, dovecot, system jobs like backup, etc) put an exclusive lock on
>> files from time to time?
>>
> I thought the entire reason (ok not the _entire_ reason but..) for  
> Maildir was to avoid locks and allow easy concurrent access to a  
> mailbox through many different applications.

Okay, so if you are real careful (use maildir instead of some other
format like mbox, don't use it for your dovecot index/control files,
don't do native backups but use a snapshot, don't involve any other
programs which might introduce locks, etc. then you can probably get
away with it.  But I still wouldn't bet on it.

> So while I do agree that file locking is a possible problem in an  
> active/active setup with FRP, I think it's possible - as long as the  
> admin is aware of the risks.

And the ways to avoid locking...  And assuming locking is the only issue
(other issues may arise depending on implementation).

> Yes, there are definitely things to be aware of.  I'm not sure if  
> this is the place to hash it out, but I think that while it's not a  
> cheap solution it may fit MY environment - and possibly others who  
> use Maildir.

OP didn't specify many details, so assumptions were made...  On my system,
I share mbox files and dovecot indexes, and they both having locking...

> I guess everyone is as cheap as I am and hasn't set it up yet :)

Uhm, DRBD is free and this suggested alternative isn't AFAIK, so I don't
think it is being cheap...  I'm thinking it is more about reputation
and install bases...

> Rick

-- 
Eric Rostetter
The Department of Physics
The University of Texas at Austin

Go Longhorns!