From owner-freebsd-questions@FreeBSD.ORG Fri Jun 18 17:17:51 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9E5D916A4CE for ; Fri, 18 Jun 2004 17:17:51 +0000 (GMT) Received: from smtpout.mac.com (smtpout.mac.com [17.250.248.88]) by mx1.FreeBSD.org (Postfix) with ESMTP id 6E26843D2D for ; Fri, 18 Jun 2004 17:17:51 +0000 (GMT) (envelope-from cswiger@mac.com) Received: from mac.com (smtpin02-en2 [10.13.10.147]) by smtpout.mac.com (Xserve/MantshX 2.0) with ESMTP id i5IHGnHF012676; Fri, 18 Jun 2004 10:16:49 -0700 (PDT) Received: from [10.1.1.193] (nfw2.codefab.com [199.103.21.225] (may be forged)) (authenticated bits=0)i5IHGj9j009663; Fri, 18 Jun 2004 10:16:48 -0700 (PDT) In-Reply-To: <200406181113.i5IBDh1E035926@dc.cis.okstate.edu> References: <200406181113.i5IBDh1E035926@dc.cis.okstate.edu> Mime-Version: 1.0 (Apple Message framework v618) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <45E449B8-C14B-11D8-99B8-003065ABFD92@mac.com> Content-Transfer-Encoding: 7bit From: Charles Swiger Date: Fri, 18 Jun 2004 13:16:44 -0400 To: Martin McCormick X-Mailer: Apple Mail (2.618) cc: freebsd-questions@freebsd.org Subject: Re: Sendmail for Large Sites X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 18 Jun 2004 17:17:51 -0000 On Jun 18, 2004, at 7:13 AM, Martin McCormick wrote: > How well does the administration of Sendmail scale up to sites > serving as many as 25,000 users? Sendmail is fine for the task, as the main issues to be concerned about have more to due with user-agents reading the mail (as in, your POP and IMAP servers), and how mailboxes are kept, than with the MTA and SMTP-level issues. > I am mainly interested in Sendmail's capacity at this time in > order to suggest it as a possibility if it is realistic to do so. Sure, sendmail can solve the problem as specified. Let me mention a book by Nick Christenson, "SENDMAIL Performance Tuning", ISBN 0-321-11570-8, because it would certainly help you, and because it has a section worth quoting here on page 10: --- 1.7 Email System Profiling More times than I care to remember, I've had a conversation with someone trying to specify an email system that went like the following: Them: I need to build an email server using Sun equipment that will handle X number of users. What hardware should I buy? Me: Well, that completely depends. Them: On what? Me: On their usage profiles. How many messages does each person send and receive each day? What is the average message size? How fast is your Internet connection? What percentage of your peak day's total traffic occur during the peak hour? [ ... ] When it comes to email servers, it seems that just about the only information anyone can obtain from a prospective client is the number of users. Unfortunately for performance purposes, this figure is just about the least useful metric for evaluating email service load. > There are other considerations such as the facts that all > incoming and outgoing messages are checked for malicious attachments. > ldap is used to drive the setting of customer mail delivery > preferences and even their user ID choice. Cyrus' IMAP and SASL software will play friendly with LDAP, as will sendmail itself. amavisd + clamav is a good solution for scanning mail for viruses and the like. You should strongly consider using maildir rather than mbox-style mail delivery. You might want to consider postfix instead of sendmail. -- -Chuck