From owner-freebsd-questions@FreeBSD.ORG Mon Nov 17 20:01:03 2008 Return-Path: Delivered-To: questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3EDC71065678 for ; Mon, 17 Nov 2008 20:01:03 +0000 (UTC) (envelope-from thomas@zaph.org) Received: from zaph.org (zaph.org [208.86.224.136]) by mx1.freebsd.org (Postfix) with ESMTP id F06ED8FC17 for ; Mon, 17 Nov 2008 20:01:02 +0000 (UTC) (envelope-from thomas@zaph.org) Received: by zaph.org (Postfix, from userid 1002) id 7AE81B96C; Mon, 17 Nov 2008 15:01:02 -0500 (EST) Date: Mon, 17 Nov 2008 15:01:02 -0500 From: "N.J. Thomas" To: Maxim Khitrov , questions@freebsd.org Message-ID: <20081117200102.GN91662@zaph.org> References: <5635aa0d0811140711t6af42ef8i762a37eb059ede19@mail.gmail.com> <20081117173845.GM91662@zaph.org> <26ddd1750811171147u5cc8f9b3k35f25c6caf9bc14f@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <26ddd1750811171147u5cc8f9b3k35f25c6caf9bc14f@mail.gmail.com> User-Agent: Mutt/1.4.2.3i Cc: Subject: Re: FreeBSD not stable enough for Xen environments? 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: Mon, 17 Nov 2008 20:01:03 -0000 * Maxim Khitrov [2008-11-17 14:47:00+0000]: > > I've not seen any problems with the clock on my RootBSD Xen system. > > I do run the ntpd in base and on average, my clock is usually only > > about 15ms away from "true UTC". > > That's interesting. Can you post your `ntpq -p` output here? Sure: $ ntpq -p remote refid st t when poll reach delay offset jitter ============================================================================== +clock.trit.net 192.12.19.20 2 u 529 1024 377 81.554 2.870 6.477 +mail.honeycomb. 192.43.244.18 2 u 408 1024 377 44.091 10.986 8.250 *tuppy.intrepidh 64.142.103.194 2 u 413 1024 377 67.709 15.626 10.327 +clock3.redhat.c 66.187.233.4 2 u 445 1024 377 147.283 24.455 9.397 +204.34.198.40 .USNO. 1 u 409 1024 377 88.746 20.620 10.405 +tick.usno.navy. .USNO. 1 u 427 1024 377 20.848 18.916 8.212 +ntp-s1.cise.ufl .GPS. 1 u 421 1024 377 45.709 18.067 9.222 LOCAL(0) LOCAL(0) 10 l 18 64 377 0.000 0.000 0.004 This is what I pretty much used to eyeball my offset earlier. > When ntpd is running, its polling interval stays very low (around 64 > seconds) because it keeps having to reset the clock. My message log is > filled with the following: Intersting, I see the same in my logs, but the frequency seems to be much less than yours, e.g. for the month of November: Nov 1 00:08:22 zaph ntpd[678]: time reset -0.129649 s Nov 3 15:33:09 zaph ntpd[678]: time reset -0.137509 s Nov 4 03:11:51 zaph ntpd[678]: time reset +0.237734 s Nov 4 03:34:23 zaph ntpd[678]: time reset -0.150326 s Nov 4 13:05:20 zaph ntpd[678]: time reset +0.317738 s Nov 4 13:32:06 zaph ntpd[678]: time reset -0.560629 s Nov 4 13:54:35 zaph ntpd[678]: time reset +0.265391 s Nov 4 15:43:55 zaph ntpd[678]: time reset -0.163660 s Nov 7 17:31:03 zaph ntpd[678]: time reset -0.130039 s Nov 10 18:29:19 zaph ntpd[678]: time reset +0.169785 s Nov 10 19:46:26 zaph ntpd[678]: time reset -0.146554 s Nov 10 20:27:08 zaph ntpd[678]: time reset +0.891811 s Nov 10 20:53:59 zaph ntpd[678]: time reset -0.774636 s Nov 10 21:35:45 zaph ntpd[678]: time reset +0.384227 s Nov 10 22:33:46 zaph ntpd[678]: time reset -0.194131 s Nov 11 12:34:25 zaph ntpd[678]: time reset +0.433002 s Nov 11 13:01:09 zaph ntpd[678]: time reset -0.335592 s Nov 11 15:17:45 zaph ntpd[678]: time reset +0.933537 s Nov 11 16:01:42 zaph ntpd[678]: time reset -0.510371 s Nov 11 17:29:41 zaph ntpd[678]: time reset -0.133244 s Nov 11 19:16:41 zaph ntpd[678]: time reset +0.191431 s Nov 11 19:42:30 zaph ntpd[678]: time reset -0.458738 s Nov 11 20:09:16 zaph ntpd[678]: time reset +0.207999 s Nov 11 20:36:06 zaph ntpd[678]: time reset +0.143897 s Nov 14 01:29:44 zaph ntpd[678]: time reset +0.134492 s Nov 15 13:13:36 zaph ntpd[678]: time reset +0.199937 s Nov 15 14:45:09 zaph ntpd[678]: time reset -0.205131 s > And so on... Could it be a problem with the hardware on host machine? > I use the same ntp.conf file on several FreeBSD 7.1 servers, and the > VPS is the only one that has this problem. I checked on my other FreeBSD boxes (all 7.0) and none of them (VPS or otherwise) exihibit this problem. > I upgraded my VPS to 7.1 a few months ago, but I don't remember if I > had this problem when using 7. Mine is a 7.0. Thomas