[pool.ntp.org] {0,1,2}.<zone>.pool.ntp.org; new monitoring system

[pool.ntp.org] {0,1,2}.<zone>.pool.ntp.org; new monitoring system

Post by Adrian 'Da » Thu, 09 Sep 2004 03:36:09

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Currently, the project consists of 220 servers, and counting steadily.
Thanks to all the volounteers donating their servers, pointing others to
the project (especially in the default configurations of various
operating system distributions!) and posting articles on web pages.

- openntp
- monitoring system
- new 0, 1, 2 subzones
- legacy time.fortytwo.ch zone

- -------

It came to my attention that OpenNTP has a serious flaw: it seems to
always report itself as a 'stratum 2' server, regardless of its true
stratum. So I ask you: please do *NOT* use this server as a server in
the pool.ntp.org project. The stratum of a timeserver is used to
prevent loops, and killing this loop detection may cause a group of
time servers to slowly run away without anyone noticing for a long

Monitoring system
- -----------------

As announced (but, of course, a few days late), I finally retired the
monitoring system as it is now and replaced it by a much simpler one.
Now, every server is just queried once per hour by a simple perl script
(using Net::NTP), and scores are assigned according to the offset
measured to my server:
+1 if offset < 0.5s
-2*$offset + 2 if 0.5s < offset < 1.5s
-2 if offset > 1.5s
-5 if server is unreachable (timeout 2s)
As with the old system, the scores are multiplied by 0.95 every hour,
too, so a opimally running server will still have a score of 20, and a
server which is offline will go to -100.

0, 1, 2, ...
- ------------

For every pool.ntp.org zone, there is now also a 0, 1 and 2.<zone>
subzone. If enough servers are available, the zones won't overlap
(europe and the global zone, I believe), for the other zones, some
servers may be present in more than one zone. But still, if you happen
to have a nameserver which does not rotate the entries, this should
mostly solve your problem.

As before, all zones are changed every hour, so that the order of the
servers will not be the same for long.

- ----------------

The project started as time.fortytwo.ch, and now I'm thinking about
retiring that zone within the next few months. So, if anybody still
has an old configuration in use, now is the time to change it from
time.fortytwo.ch to pool.ntp.org.

Ok, that's it for now. Web page changes to reflect this newsletter, and
some more web site translations, are next in the pipeline, but with me
starting a new Job, time is a bit crowded.

- -- vbi

- --
Beware of the FUD - know your enemies. This week
* The Alexis de Toqueville Institue *

Version: GnuPG v1.2.4 (GNU/Linux)
Comment: get my key from http://www.yqcomputer.com/


1. NTP does not sync when using pool.ntp.org

2. [ntp:questions] [pool.ntp.org] 87 servers so far /web server configuration / some other small things

I started the discussion with trying to figure out how to force pool.ntp.org
into a more tree-like hierarchy with a smallish number of Stratum 1's feeding
a larger number of Stratum 2's that were publicly available. While that's
a fine goal, that's not how pool.ntp.org works, and I eventually
became convinced that the centralized administration to *force* that to happen
is probably not the right way to go. (It should still be encouraged, of

With respect to server quality... Trying to outsmart ntpd's highly
evolved falseticker determiniation is a Bad Thing. Using
statistics gathered via ntpdc from a broad set of pool.ntp.org clients
will indeed be more useful than single-central-point monitoring.

Right now my thinking is heavily influenced by Minar's 1999 NTP survey,
but trying to take it a step further and evaluating quality locally rather
than from a central point. (Minar and the other referenced surveys had
the advantage of a relatively fat pipe to everywhere around the world).


3. Why so many dead NTP servers in pool.ntp.org?

4. pool.ntp.org large spikes?

5. pool.ntp.org DNS errors & warnings

6. [pool.ntp.org] 87 servers so far / web server configuration / some other small things

7. problem in ntpd in resoving pool.ntp.org

8. [pool.ntp.org project] The Future is Bright, The Future is ...

9. pool.ntp.org empty ?

10. pool.ntp.org project homepage translation into Spanish

11. pool.ntp.org down?

12. pool.ntp.org?

13. Bad NTP servers jeopardizing the pool.ntp.orginitiative

14. [Pool] NTP Pool Servers and DynDNS

15. IPv6 support for NTP - need ntp.org code archive for it