Hi,
   IMHO, quotas on mail file systems are a bad, bad idea.  You don't ever
want to loose email because a file system filled up or a user hit their
quota (something they can't control if they aren't around to check email).

   Disk is cheap, buy more if your mail spool starts filling up.  I use
a 8 GB mail spool for 3000 users (with another 8+ GB in reserve).  During
the worst time in the summer when the students are gone, it will get about
30% full.  If it ever gets to 50% full, I will add more disk.

   For those POP users who insist on using the "leave mail on server" option,
I have a perl script that will read a standard mbox format file and delete
messages based on different criteria (I didn't write the script).  I run
a cron job every week that deletes any message that has been opened for
reading AND is more than 30 days old.  This keeps the old drek cleaned
out of the mail spool.  The user community knows about this policy.

** Jeff A. Earickson, Ph.D                         PHONE: 207-872-3659
** Senior UNIX Sysadmin, Information Technology    EMAIL: [EMAIL PROTECTED]
** Colby College, 4214 Mayflower Hill,               FAX: 207-872-3076
** Waterville ME, 04901-8842
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---------- Forwarded message ----------
Date: Fri, 9 Aug 2002 12:53:18 -0400
From: "Alan W. Rateliff, II" <[EMAIL PROTECTED]>
To: Subscribers of Qpopper <[EMAIL PROTECTED]>
Subject: Re: Filesystem quotas

----- Original Message -----
From: "Michael Kolos" <[EMAIL PROTECTED]>
To: "Subscribers of Qpopper" <[EMAIL PROTECTED]>
Sent: Friday, August 09, 2002 9:17 AM
Subject: Re: Filesystem quotas


> What is this "boundary condition" and when does it come up?
> We have the temp dir on a non-quota filesystem, and on the spool dir users
> have a hard quota 100k more than the soft quota.
> Yet we still occasionnally end up with a user with a corrupted mail spool
> because somehow it went over quota, and when qpopper copies the spool
back,
> it gets corrupted.
> I have tried turning off the X-UIDL writing, but that hasn't helped.

Imagine a user with a 5120k hard quota, and 4.9MB in their mailfile.
QPopper copies that mailfile over to the non-quota filesystem to POP it out,
and while the user is checking his/her email (and apparently NOT deleting it
from the server) they receive a 200k email.  Now there's 200k in their
mailfile, only 4.8MB available.  The POP session is over and QPopper copies
the .pop file back into the mail spool.  0.2MB + 4.9MB = 5.1MB > 5.0MB: the
user is now over quota, and the last 100k or so is lost.

That was my concern.  But frankly, I don't like my users leaving their mail
on the server.  But that's not an entirely practical requirement when some
people have multiple machines/people checking the same box (which I
recommend multiple boxes with aliases) or using webmail as their primary or
only mail viewing agent.

But, that's what happens.  I haven't decided if it would be nicer to have
quota systems installed in the local mail delivery agent or not, as it would
require a separate database of user quotas.  I think procmail can do that,
but I'm only beginning to learn about it.

--
Alan W. Rateliff, II

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