From owner-freebsd-questions@FreeBSD.ORG Thu May 3 15:07:41 2007 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 4304A16A401 for ; Thu, 3 May 2007 15:07:41 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from pi.codefab.com (pi.codefab.com [199.103.21.227]) by mx1.freebsd.org (Postfix) with ESMTP id 13EC913C44C for ; Thu, 3 May 2007 15:07:41 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from localhost (localhost [127.0.0.1]) by pi.codefab.com (Postfix) with ESMTP id 4300B5C75; Thu, 3 May 2007 11:07:40 -0400 (EDT) X-Virus-Scanned: amavisd-new at codefab.com Received: from pi.codefab.com ([127.0.0.1]) by localhost (pi.codefab.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id eljnvfCH76pO; Thu, 3 May 2007 11:07:38 -0400 (EDT) Received: from [192.168.1.3] (pool-96-224-43-99.nycmny.east.verizon.net [96.224.43.99]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by pi.codefab.com (Postfix) with ESMTP id A03385C33; Thu, 3 May 2007 11:07:37 -0400 (EDT) Message-ID: <4639FAB6.9050701@mac.com> Date: Thu, 03 May 2007 11:07:34 -0400 From: Chuck Swiger User-Agent: Thunderbird 1.5.0.10 (Windows/20070221) MIME-Version: 1.0 To: "illoai@gmail.com" References: <20070503014137.I3544@duane.dbq.yournetplus.com> <20070503015723.S3544@duane.dbq.yournetplus.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-questions@freebsd.org, Duane Hill Subject: Re: Time Synchronizing Between Two Servers X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 03 May 2007 15:07:41 -0000 illoai@gmail.com wrote: [ ... ] > It may very well be noisier than just serving out ntp > to the local network, what with talk about elections > and such every 4 minutes, but generally everything > is kept within 0.050 seconds (and running ntpd on > all of the local machines feels like serious overkill). Simply setting the date upon system boot and maybe once a day using cron to call ntpdate or whatever is probably good enough for any client machine, and OK for non-important servers where the exact timekeeping doesn't matter much. ntpd is tiny by modern standards-- it's much smaller than a single Perl or Apache httpd+mod_Perl/PHP/whatever child process. :-) Normally, you choose your three (or more) most important servers, and run NTPd on them in a peer-aware ring with some external servers from the NTP pool, and then call ntpdate or run ntpd against only your local NTP resources for the rest of your machines. Sun SPARC machines have good HW clocks, and also some of the newer Macs also seem to have consistently low values in ntp.drift and handle timekeeping well. -- -Chuck