Sam wrote:
> Stefan Osterman writes:
>
> > I need some advice how to install a Qmail system that can handle 20k users
> > scaling up to 200k users. The system should handle mulitple domains and not
> > use the /etc/passwd file. Each Maildir should have quota whith mail
> > notification to user, sender and maybe some other address.
>
> Incoming mail should be handled by qmail-users, it will scale.
>
> If you're ok with POP3/IMAP users logging in using their UNIX ids, you're
> all set. If you want users to login under their virtual domains, vchkpw
> won't work because it won't scale - it scans a flat file for user
> validation.
I'm jumping into this thread, as I'm in a very similar position. I'm a little
leery of using uid's, because (from my understanding) they're a signed 16-bit
field, meaning that only 32K users can actually operate (on a 2.0.36 Linux
system).
> Write a custom checkpassword checking routine, using something like GDBM to
> validate userid/domains.
Ideally, I'd like to use the radius patch in conjunction with this. I haven't
yet downloaded the patch or read the DOC's, as I'm in the middle of somewhat
time-intensive DNS migration, but I'm not exactly positive where it would get
it's home-dir information for use with Maildir's ... our Cistron radius server
certainly doesn't have that information available to server out the way thigns
stand now :-)
> Qmail has no builtin quota support. Write a custom script that sweeps
> through all the mailboxes, notifies owners which exceed their soft quota,
> and locks out mail delivery to mailboxes that exceed their hard quota.
> Modify your POP3/IMAP server to unlock mailboxes, if necessary, after mail
> is deleted.
Would not the hard quota itself lock out delivery, or is there some "might break
qmail" issue that I'm missing? I'm perfectly content with a bounce mentioning
disk space, as the users are well aware of the 10Mb limit that we are currently
imposing on our soon-to-be-replaced mail system.
> Get a separate RAID box, move all the disks there, and put it on the
> network. Have both machines mount the same filesystem, and use it as the
> mail store, using Maildirs. The machines should have only enough disk
> space to run the OS, plus sufficient disk space for your active mail queue.
I'm not all that worried about throughput in my situation, as the current mail
server is handling the load just fine. I'm looking for a solution that lets me
use radius (to consolidate the user database at long last :-) for authentication,
ideally for more than 32K users (we're at 10K now) and even more ideally in an
automated fashion, such that adding a user to the radius database automatically
adds their mail store dir. I'm not yet started on the planning for this project,
so this might be more simple than it appears to me at the moment.
-Tillman Hodgson
