Thank you for the information. It is REALLY good to see not just the problem but reason why behind it. Would setting up Peer servers help you think? or would it still need to access server a to forward to server c?
Thanks, Mark Mitchell ----- Original Message ----- From: "R. Scott Perry" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, November 19, 2003 5:11 PM Subject: Re: [IMail Forum] telnet localhost 25 connection failed > > > I am still having a major problem. I have a Imail 7 server that about 50% > >of the time, when I telnet to port 25 I get connection failed. I get the > >same connection failed message even if I do it form the server and telnet to > >localhost 25. But them sometimes it goes thru. First I know people will > >say the NIC. It has been changed to 3 different ones to rule them out. > > It's not the NIC -- if the problem happens when telneting to localhost, it > can't be the NIC. > > >Another weird thing is, I have zero problem at all telneting to port 110. > > That, combined with: > > >The server gets atleast 500,000 emails a day to it. > > would suggest that you are approaching the limits of the server. Although > IMail technically is supposed to be able to support a very large (500+?) > number of simultaneous incoming E-mails, in reality there seems to be a > limit much, much lower than that (less than 100). When that limit is > reached, IMail chokes (it doesn't respond on port 25, instead of sending a > "421" response). At 500,000 E-mails/day, you're dealing with about 6 > E-mails/second -- at an average of 5 seconds per E-mail, that's an average > of 30 simultaneous E-mails. During peak times, it would be higher. > > The other issue is that IMail's architecture allows for a hard limit of > about 30 delivery processes, giving you about 5 seconds to optionally scan > and deliver each E-mail. For unscanned incoming E-mail, that's not > normally a problem (it is just a matter of updating the user's mailbox > file). But for outgoing E-mail or scanned E-mail, you have to be very, > very careful. > > There are a number of IMail customers handling over 500,000 E-mails/day on > a single server (we know because we have customers processing those > volumes), but it has to be done very carefully. For example, if the > partitioning isn't handled well, you're going to reach maximum capacity > sooner than you otherwise would. > > -Scott > --- > Declude JunkMail: The advanced anti-spam solution for IMail mailservers. > Declude Virus: Catches known viruses and is the leader in mailserver > vulnerability detection. > Find out what you've been missing: Ask about our free 30-day evaluation. > > --- > [This E-mail was scanned for viruses by Declude Virus (http://www.declude.com)] > > > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html > List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ > Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
