From owner-freebsd-questions@freebsd.org  Sun Aug 14 15:46:17 2016
Return-Path: <owner-freebsd-questions@freebsd.org>
Delivered-To: freebsd-questions@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 4870ABBAF6B
 for <freebsd-questions@mailman.ysv.freebsd.org>;
 Sun, 14 Aug 2016 15:46:17 +0000 (UTC) (envelope-from carlj@peak.org)
Received: from filter03.peakinternet.com (filter03.peakinternet.com
 [207.55.16.94])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id 1B659138B
 for <freebsd-questions@freebsd.org>; Sun, 14 Aug 2016 15:46:16 +0000 (UTC)
 (envelope-from carlj@peak.org)
Received: from zmail-mta02.peak.org ([207.55.16.112])
 by filter03.peakinternet.com ({a3d4bcbc-467e-4baf-8e5e-c89ccb4fcca2})
 via TCP (outbound) with ESMTPS id 20160814154238206_0000
 for <freebsd-questions@freebsd.org>; Sun, 14 Aug 2016 08:42:38 -0700
X-RC-FROM: <carlj@peak.org>
X-RC-RCPT: <freebsd-questions@freebsd.org>
Received: from zmail-mta02.peak.org (localhost [127.0.0.1])
 by zmail-mta02.peak.org (Postfix) with ESMTPS id 68A7118CC56
 for <freebsd-questions@freebsd.org>; Sun, 14 Aug 2016 08:42:40 -0700 (PDT)
Received: from localhost (localhost [127.0.0.1])
 by zmail-mta02.peak.org (Postfix) with ESMTP id 4E60818CC57
 for <freebsd-questions@freebsd.org>; Sun, 14 Aug 2016 08:42:40 -0700 (PDT)
Received: from zmail-mta02.peak.org ([127.0.0.1])
 by localhost (zmail-mta02.peak.org [127.0.0.1]) (amavisd-new, port 10026)
 with ESMTP id 6Y5m2l71yqP3 for <freebsd-questions@freebsd.org>;
 Sun, 14 Aug 2016 08:42:40 -0700 (PDT)
Received: from mailproxy-lb-06.peak.org (mailproxy-lb-06.peak.org
 [207.55.17.96])
 by zmail-mta02.peak.org (Postfix) with ESMTP id 1880914C825
 for <freebsd-questions@freebsd.org>; Sun, 14 Aug 2016 08:42:40 -0700 (PDT)
Received: from carlj by elm.localnet with local (Exim 4.87 (FreeBSD))
 (envelope-from <carlj@elm.localnet>) id 1bYxYZ-000N79-JZ
 for freebsd-questions@freebsd.org; Sun, 14 Aug 2016 08:42:35 -0700
From: Carl Johnson <carlj@peak.org>
To: freebsd-questions@freebsd.org
Subject: Re: General NTP questions
References: <57B08E5A.7010600@sneakertech.com>
X-Clacks-Overhead: GNU Terry Pratchett
Date: Sun, 14 Aug 2016 08:42:35 -0700
In-Reply-To: <57B08E5A.7010600@sneakertech.com> (quartz@sneakertech.com's
 message of "Sun, 14 Aug 2016 11:29:30 -0400")
Message-ID: <86twen8ihg.fsf@elm.localnet>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (berkeley-unix)
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
X-MAG-OUTBOUND: peakinternet.redcondor.net@207.55.16/22
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-questions>, 
 <mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions/>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
 <mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 14 Aug 2016 15:46:17 -0000

Quartz <quartz@sneakertech.com> writes:

> In general, do FreeBSD and related OSs (Dragonfly, OSX, etc) have ways
> of restricting the ntp drift to always be within certain known-sane
> parameters, and/or ways of manually adjusting the drift on the fly
> without having to stop and restart ntpd?

I think the -f option to ntptime(8) will adjust it as you want, but I
don't know how to limit it.  I think the only limits are that it has to
be within =C2=B1500ppm.
--=20
Carl Johnson		carlj@peak.org