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Re: pool.ntp.org NTP servers
From: wayne <wayne () midwestcs com>
Date: Tue, 03 Jun 2003 11:52:57 -0500

In <20030603160008.GA15027 () OZoNE TZoNE ORG> Phillip Vandry <vandry () TZoNE ORG> writes:

On Sun, Jun 01, 2003 at 09:41:39AM -0500, wayne wrote:

This seems like a good time to put in a plug for the pool.ntp.org NTP
servers.  This is collection of public ntp servers provided by
individuals and ISP's placed in a round-robin DNS system.  The goal is

Following other advice earlier in this thread, wouldn't it be better to
hand pick NTP servers that you know you have a symmetric route to?


I've gotten a fair amount of response to my plug for the pool.ntp.org
project, however, it appears that I wasn't very clear about what the
project is.

First off, I'm not in charge of the pool.ntp.org project, so I can't
add any servers to the pool.  The admin email address you should
contact if you can provide a server is: clockmaster () fortytwo ch

Secondly, the pool.ntp.org servers aren't all stratum-1, some are even
stratum-3 or so.  The goal here isn't to provide everyone with the
absolute best time standard, but to provide everyone with a good
enough time standard that you can just plop pool.ntp.org in without
thinking too much about it.  Actually, this project started out as a
way to try and keep people from abusing stratum-1 time sources by
plopping in a fixed list as a default.

For example, the Debian Linux distribution now comes with three
pool.ntp.org servers picked at random from the round-robin DNS as a
default.  Since you don't know where in the world or on what networks
these Linux installations will be placed, picking three random NTP
sites is far better than picking a fixed list or picking nothing at
all.  People who care about sub 10ms accuracy will go find better time
sources, but most people just want sub 1min accuracy.

Again, if you can either provide a public ntp server, or you can
influence people to use the pool.ntp.org servers instead of abusing
other servers, please check out: http://fortytwo.ch/time/

Of course, your users should be using ISP or company specific NTP
servers if they can, if they can't, using pool.ntp.org is better.


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