Re: Debian's mail daemons

[Philip Hands <phil@hands.com>]

> On Wed, 18 Jun 1997, Philip Hands wrote:
> 
> > I think we should also consider switching to Maildir/ format for mail
> > drops, since it seems to be the only way for delivering mail securely
> > over NFS.
> 
> procmail does also deliver mail securely over NFS.
> (At least this is what the documentation says, I have not tested it
> personally).

To quote the maildir(5) man page:

       A machine may crash while it is delivering a message.  For
       both mbox files and mh folders this means that the message
       will  be silently truncated.  Even worse: for mbox format,
       if the message is truncated in the middle of  a  line,  it
       will  be  silently  joined  to the next message.  The mail
       transport agent will try again later to deliver  the  mes­
       sage,  but  it  is  unacceptable  that a corrupted message
       should show up at all.  In maildir, every message is guar­
       anteed complete upon delivery.

       A  machine may have two programs simultaneously delivering
       mail to the same user.  The mbox and  mh  formats  require
       the programs to update a single central file.  If the pro­
       grams do not use some locking mechanism, the central  file
       will  be corrupted.  There are several mbox and mh locking
       mechanisms, none of which work portably and reliably.   In
       contrast,  in  maildir, no locks are ever necessary.  Dif­
       ferent delivery processes never touch the same file.

Procmail solves the locking over NFS problem, but does not address the crash 
problem described above (AFAIK).  This means that mbox mail folders are not 
reliable for local delivery, let alone over NFS.

Cheers, Phil.



--
TO UNSUBSCRIBE FROM THIS MAILING LIST: e-mail the word "unsubscribe" to
debian-devel-request@lists.debian.org . 
Trouble?  e-mail to templin@bucknell.edu .