From owner-freebsd-questions Sat Oct 24 19:54:04 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id TAA29117 for freebsd-questions-outgoing; Sat, 24 Oct 1998 19:54:04 -0700 (PDT) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from allegro.lemis.com (allegro.lemis.com [192.109.197.134]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id TAA29112 for ; Sat, 24 Oct 1998 19:54:01 -0700 (PDT) (envelope-from grog@freebie.lemis.com) Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by allegro.lemis.com (8.9.1/8.9.0) with ESMTP id NAA04650; Sun, 25 Oct 1998 13:23:12 +1030 (CST) Received: (from grog@localhost) by freebie.lemis.com (8.9.1/8.9.0) id NAA16908; Sun, 25 Oct 1998 13:23:06 +1030 (CST) Message-ID: <19981025132306.F16609@freebie.lemis.com> Date: Sun, 25 Oct 1998 13:23:06 +1030 From: Greg Lehey To: Dan Nelson , Brendan Kosowski , FreeBSD Questions Subject: Re: Time calibration ? References: <19981024201015.B29492@emsphone.com> <19981025124740.D16609@freebie.lemis.com> <19981024212131.A1534@emsphone.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.91.1i In-Reply-To: <19981024212131.A1534@emsphone.com>; from Dan Nelson on Sat, Oct 24, 1998 at 09:21:31PM -0500 WWW-Home-Page: http://www.lemis.com/~grog Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 X-Mutt-References: <19981024212131.A1534@emsphone.com> Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Saturday, 24 October 1998 at 21:21:31 -0500, Dan Nelson wrote: > In the last episode (Oct 25), Greg Lehey said: >> On Saturday, 24 October 1998 at 20:10:15 -0500, Dan Nelson wrote: >>> Your ISP seems to run one two hops away from you at >>> Fddi0-0.lon7.Melbourne.telstra.net (139.130.239.228). >> >> Innteresting. Where did you discover this server? It's not in the >> lists, and it turns out to be the most accessible for me as well. > > My standard procedure. I traceroute the user, then ntptrace the last 3 > or 4 hops :) Cisco servers have NTP client/server functionality built > in, so many border routers can be used as NTP servers. Lots of ISPs > may also have an "official" server; I sometimes check to see if ntp. > date. or mail.domain.com respond to NTP queries. Thanks. I've learnt something. It also shows it's worth checking on these things: first, there's a good chance that Telstra doesn't want people to use this server (which is only stratum 3, and thus not in the lists under http://www.eecis.udel.edu/~mills/ntp/servers.htm), and secondly you're not necessarily buying anything by using it. Until I read your message, I was using terss.hba.marine.csiro.au, which is stratum 1. Here's the output of ntptrace for each server: Fddi0-0.lon7.Melbourne.telstra.net: $ ntptrace allegro allegro.lemis.com: stratum 5, offset 0.011220, synch distance 0.44196 freebie.lemis.com: stratum 4, offset -0.004778, synch distance 0.42136 Fddi0-0.lon7.Melbourne.telstra.net: stratum 3, offset -0.008361, synch distance 0.02402 lon-core1.Melbourne.telstra.net: stratum 2, offset -0.006531, synch distance 0.02254 terss.hba.marine.csiro.au: stratum 1, offset -0.013036, synch distance 0.00549, refid 'GPS' terss.hba.marine.csiro.au: $ ntptrace allegro allegro.lemis.com: stratum 3, offset -0.001456, synch distance 0.10211 freebie.lemis.com: stratum 2, offset -0.000076, synch distance 0.10406 terss.hba.marine.csiro.au: stratum 1, offset 0.019836, synch distance 0.00343, refid 'GPS' In other words, although terss.hba.marine.csiro.au is further from here than Fddi0-0.lon7.Melbourne.telstra.net, I get better time synchronization. Greg -- See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message