From owner-freebsd-questions@FreeBSD.ORG Tue Apr 21 17:44:03 2009 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 6C02C106566B for ; Tue, 21 Apr 2009 17:44:03 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from asmtpout015.mac.com (asmtpout015.mac.com [17.148.16.90]) by mx1.freebsd.org (Postfix) with ESMTP id 57D9F8FC17 for ; Tue, 21 Apr 2009 17:44:03 +0000 (UTC) (envelope-from cswiger@mac.com) MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Received: from cswiger1.apple.com ([17.227.140.124]) by asmtp015.mac.com (Sun Java(tm) System Messaging Server 6.3-8.01 (built Dec 16 2008; 32bit)) with ESMTPSA id <0KIG006L9P8IHB50@asmtp015.mac.com> for freebsd-questions@freebsd.org; Tue, 21 Apr 2009 10:43:30 -0700 (PDT) Message-id: From: Chuck Swiger To: Mel Flynn In-reply-to: <200904211106.01965.mel.flynn+fbsd.questions@mailing.thruhere.net> Date: Tue, 21 Apr 2009 10:43:30 -0700 References: <200904211106.01965.mel.flynn+fbsd.questions@mailing.thruhere.net> X-Mailer: Apple Mail (2.930.3) Cc: freebsd-questions@freebsd.org Subject: Re: Preventing ntpd from adjusting time (backwards) 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: Tue, 21 Apr 2009 17:44:03 -0000 Hi, Mel-- On Apr 21, 2009, at 2:06 AM, Mel Flynn wrote: > Some coarse reading of ntpd(8) and ntp.conf(5) doesn't lead me to > believe it's > possible to make ntpd *not* adjust the time. With adjust I don't > mean the skew > operation, but really change the time. Perhaps I've missed it elsewhere in this thread, but I don't believe anyone actually answered the original question, which would be to use: -x, --slew Slew up to 600 seconds. Normally, the time is slewed if the offset is less than the step threshold, which is 128 ms by default, and stepped if above the threshold. This option sets the threshold to 600 s, which is well within the accuracy window to set the clock manually. [ ... ] It should be surprising that your clock would jump by 6 seconds. Do you have adequate upstream timesources (ie, at least 4) configured, is your local HW clock busted somehow, or are you doing something odd with power-savings mode or running in a VM or something...? Regards, -- -Chuck