At 1:10 PM -0400 8/9/02, Jeff A. Earickson wrote:
>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).

I'm a partial believer in mail spool quotas.  I don't believe there 
should be a quota set that we should expect users to ever reach 
within reason.  ie, basic mail usage shouldn't hit this quota.  I am 
however in favor or a high hard quota to save my mail filesystem. 
I've seen on a couple occasions (at other places) where an auto-ack 
script started looping in a bad bad way.  The auto-ack sent a survey 
to users that hadn't mailed our tech support list in 3 months.  It 
also CCd the team leaders.  One of team leaders left.  Mail to him 
was bouncing.  The From: was set to the list.  IIRC mailer-daemon was 
on an exclude list on the auto-ack, excluded from being recorded as a 
recipient of the survey.  Each bounce to that user went back to the 
auto-ack and so on and so forth.  Before all was said and done, the 
remaining team leaders mail spools were multi-Gig in size.  I'm a big 
fan of a hard quota of a reasonably high number because of this. 
This keeps your mail system from filling up which would cause a loss 
of mail to all users, not just the one that caused the failure.

I don't think a 100MB hard quota is unreasonable.  If a user was gone 
for an extended period of time (say a year for medical reasons or on 
a sabatical), then they should follow common Email Etiquette and 
unsub from all mailing lists.  If they don't, they deserve to have 
mail bounce.

I'm also a fan of a soft quota with an infinite grace period.  The 
reason being is I plan on using repquota in a script to mail users' 
spools that excede a certain size (maybe 15MB).  I'd send them a form 
letter explaining how to configure their MUA to remove mail from 
server among other things.  I'd run this nightly.  The first mailing 
would go only to the user.  Subsequent mailings would also go to an 
admin so the admin could call the user.  Note that I'm not using the 
soft quota to strictly limit the user's spool size.  I'm just using 
it as a reporting tool.


>    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.

I like having a buffer too.  Sometimes though the filesystem fills 
overnight, or in a matter of hours.  That's where the reasonably high 
hard quota comes in handy.  If one of my users hit a 100MB hard quota 
and they're following my guidelines for deleting mail from the 
server, I know something is wrong.  They should too I would think.

>    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.

I've been searching from such a script.  I found a user with mail 
dating back to '97 yesterday. :)  Would you mind sharing it?

Thanks
  Justin

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