Jason,
Thanks. :-)
Do you have a recommendation for the tarpit? Some of the others, e.g.,
filtering during the SMTP session, will have to be postoned for later, but I
can see how to do a tar pit fairly quickly, and I would like to discourage
people from spending my transfer. Can you suggest reasonble parameters that
have worked in the real-world?
Yes, Danny, the tarpit will be fully controllable via the config.xml file,
and will default to off.
--- Noel
-----Original Message-----
From: Danny Angus [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, August 20, 2002 5:12
To: James Developers List
Subject: RE: Lots of twisty, er, servers all the same ...
Jason,
Thanks for that insight. James as you've rightly guessed isn't suited to big
volumes, its better suited to lower volume traffic which requires
complicated processing. That said increasing throughput is a goal and your
points will be helpful.
d.
> -----Original Message-----
> From: Jason Webb [mailto:[EMAIL PROTECTED]]
> Sent: 20 August 2002 09:08
> To: 'James Developers List'
> Subject: RE: Lots of twisty, er, servers all the same ...
>
>
> On a related note...
> I used to run a mail system with 2 million+ deliveries per day. We came
> across some intresting issues during very high-volume email transmission
> (and no it wasn't spam). We used Qmail and EzMLM (with a DB backend)
>
> 1) Limit the number of delivery threads on a per-domain basis. This is
> very imporant if you have a lot of users with AOL accounts (or ATT for
> that matter :-)).
> 2) Agressively "cull" SMTP sessions that last longer than say 10
> minutes. This stops a trivial DOS attack clogging up the mail server
> 3) Timeout the delivery threads with an exponential back-off (Not sure
> if this is done already)
> 4) Up-front spam rejection. Tell blocked senders and spammers to ****
> off in the SMTP handler, not just within the mail processor itself. This
> will cut down on server load.
> 5) Tar-pitting - slowing down connections that do a lot of "RCPT TO:" -
> again using an exponential back-off
>
> These are a few things that James needs to do to make a real-world,
> volume solution. Qmail is not an elegant solution, but it is fast...
>
> -- Jason
--
To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]>
For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
