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 > > -----Original Message----- > From: Noel J. Bergman [mailto:[EMAIL PROTECTED]] > Sent: 20 August 2002 04:48 > To: James-Dev Mailing List > Subject: Lots of twisty, er, servers all the same ... > > > As you can see from the nslookup of ATT.NET that follows, they have lots > of MX records, all the same IP address. On nights like tonight when > AT&T is jammed, this can block a delivery thread for over an hour. > > Is there a reason why getMailServers [actually, > DNSServer.findMXRecords()] should not return a collection containing > only one entry per IP address? > > --- Noel > > > set q=mx > > att.net > Server: MACU.MA.MT.NP.ELS-GMS.att.net > Address: 199.191.145.136 > > att.net MX preference = 5, mail exchanger = gateway1.att.net att.net MX > preference = 5, mail exchanger = gateway2.att.net att.net MX preference > = 5, mail exchanger = gateway3.att.net att.net MX preference = 5, mail > exchanger = gateway4.att.net att.net MX preference = 5, mail exchanger = > gateway5.att.net att.net MX preference = 5, mail exchanger = > gateway6.att.net att.net MX preference = 5, mail exchanger = > gateway8.att.net att.net nameserver = ohcu.oh.mt.np.els-gms.att.net > att.net nameserver = macu.ma.mt.np.els-gms.att.net att.net nameserver = > orcu.or.br.np.els-gms.att.net att.net nameserver = > wycu.wy.br.np.els-gms.att.net > gateway1.att.net internet address = 204.127.134.23 > gateway2.att.net internet address = 204.127.134.23 > gateway3.att.net internet address = 204.127.134.23 > gateway4.att.net internet address = 204.127.134.23 > gateway5.att.net internet address = 204.127.134.23 > gateway6.att.net internet address = 204.127.134.23 > gateway8.att.net internet address = 204.127.134.23 > ohcu.oh.mt.np.els-gms.att.net internet address = 199.191.144.75 > macu.ma.mt.np.els-gms.att.net internet address = 199.191.145.136 > orcu.or.br.np.els-gms.att.net internet address = 199.191.129.139 > wycu.wy.br.np.els-gms.att.net internet address = 199.191.128.43 > > > > > -- > To unsubscribe, e-mail: > <mailto:[EMAIL PROTECTED]> > For additional commands, e-mail: > <mailto:[EMAIL PROTECTED]> > > > > -- > To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
