From owner-freebsd-questions@FreeBSD.ORG Thu May 15 21:16:20 2008 Return-Path: Delivered-To: FreeBSD-Questions@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id BFF7C106566C for ; Thu, 15 May 2008 21:16:20 +0000 (UTC) (envelope-from ccowart@rescomp.berkeley.edu) Received: from hal.rescomp.berkeley.edu (hal.Rescomp.Berkeley.EDU [169.229.70.150]) by mx1.freebsd.org (Postfix) with ESMTP id AA3558FC19 for ; Thu, 15 May 2008 21:16:20 +0000 (UTC) (envelope-from ccowart@rescomp.berkeley.edu) Received: by hal.rescomp.berkeley.edu (Postfix, from userid 1225) id 96B173C0507; Thu, 15 May 2008 14:16:20 -0700 (PDT) Date: Thu, 15 May 2008 14:16:20 -0700 From: Christopher Cowart To: FreeBSD-Questions@FreeBSD.org Message-ID: <20080515211620.GH18488@hal.rescomp.berkeley.edu> Mail-Followup-To: FreeBSD-Questions@FreeBSD.org References: <20080515185758.GA12709@ikarus.thalreit> <20080515210819.GA12605@Grumpy.DynDNS.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Q6STzHxy03qt/hK9" Content-Disposition: inline In-Reply-To: <20080515210819.GA12605@Grumpy.DynDNS.org> Organization: RSSP-IT, UC Berkeley User-Agent: Mutt/1.5.16 (2007-06-09) Cc: Subject: Re: time drift 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, 15 May 2008 21:16:20 -0000 --Q6STzHxy03qt/hK9 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable David Kelly wrote: > Its PC commodity-grade. Not all that unusual even for stuff sold > claiming to be a "server". This is in no small part why ntpd exists. >=20 > nptd calculates a correction coefficient and (under FreeBSD) stores it > in /var/db/ntpd.drift for use on next start so as to more quickly > establish a lock. >=20 > So in short ntpd calibrates your clock in order to minimize the > corrections required. Is The Right Thing To Do. We run a large number of FreeBSD servers under vmware. We've seen ntpd silently die, because the drift becomes "insane." What do others do in this situation? (We've resorted to croning ntpdate for VMs.) --=20 Chris Cowart Network Technical Lead Network & Infrastructure Services, RSSP-IT UC Berkeley --Q6STzHxy03qt/hK9 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) iQIVAwUBSCyoJCPHEDszU3zYAQKaAg/+Lgd8o/4rU9ldvojtshE/xrkForQZkewe ddrFRUFf5cUL5epyQeWH0bMs9c0Jw1eDIOiizzoD87ZBbfiINT4MVhmA+5XI//g3 zrmv50ucYLGICRDpjv+TSx8/9OCARHSTrM2ZL0lanxjhqUcrR+GBVtJGD3BOpzwv Blo7WopaD3bT3t3acRVQn9Rt1qE/SQVMeokewrHwZ6FkZVEGPQ/SWHtx1EGweQOz K4Wj9KzybMeLnduSPvAyO7+fWUarbizIqgDyT+5krVojHruw3gJwnotp6Vwu42fN ueNxK4wKH3lPzKzUjzYHKRHrJk1/pbejuSB5eBqmHqF3SI10IbRatlBedYNk3Cod szP53UBoSqz1U/zBoL1pxt5vJRq7hAQCXcS8r7NTgwLSjjXlEa86dZSFMoiues89 kT7HOeyn7frmmzYBW+e7e0XaL/sEG1azLZIYwZebj/EEv+t1d3s1fLRRJKgifSIa CSInkQ7BcvDXEHQlXyNM8Sl9Z5i+CkAY5DgP++7uItLY+X40LfI4VqbLMqD4azL9 sQeZXYawcX52rv2/i51WUlOXiHNNbqgOgUgrdbIUgvAq/L/KadNJqwZp9rAft1sh 348T2+zxTiDGZDMWrDB6Cqh0gHzA79Lk4tkQC6LsCzYOkIA5X+1k5D0q5SiqBSfz NDHEmXTtMlM= =3s4T -----END PGP SIGNATURE----- --Q6STzHxy03qt/hK9--