[OpenAFS] maildir on openafs

[Robert Banz]

On Apr 8, 2008, at 9:49 AM, Russ Allbery wrote:

> "David Bear" <David.Bear@asu.edu> writes:
>
>> I seem to distantly recall some discussion about storing maildir
>> directories on openafs, but I don't remember if it was safe,
>> discouraged, or otherwise problematic. Any one see problems with  
>> putting
>> maildir in afs?
>
> The maildir protocol requires cross-directory hardlinks.  In order  
> to use
> it in AFS, you have to modify the protocol slightly in a way that may
> undermine some of its reliability guarantees (although *probably* not
> fatally).

Changing the operation that uses to a rename() is actually fine.

The problem with maildir is that many of the IMAP-maildir drivers use  
stat() information to store the message's IMAP UUID, and stat() is a  
rather expensive operation in AFS.

In my case, I had written a c-client driver which stored the UUID in  
the filename of the maildir message, which got around this -- and  
there's also an issue regarding UUID generation which is best  
implemented with a lock that to guarantee correct generation.

Its a mess.  AFS is not for mail. Unix "user accounts" are not for  
mail.  Use an actual mail system and do it right ;)

-rob