[ntp:questions] Stratum 1 servers in pools?!?

Richard B. Gilbert rgilbert88 at comcast.net
Mon Jun 15 23:26:34 UTC 2009

Rich wrote:
> I'm using ntpd 4.2.4p4 on several Ubuntu 9.04 ("Jaunty") servers.
> Recently, I've been reconfiguring some of my servers to use the "pool"
> DNS names (e.g., "server 0.us.pool.ntp.org").  I've noticed that I
> sometimes end up associating with a stratum-1 server from a pool.  As
> an experiment, I specified 0.de.pool.ntp.org (the German pool), and
> one of my servers is currently syncing to zit-net2.uni-paderborn.de (a
> stratum-1 server currently syncing to a DCF77 clock).  I've seen this
> a couple of times with the US pool as well -- though I'm afraid it
> didn't occur to me at the time to write down the stratum-1 servers
> involved.
> Since (as I understand) end-user clients should avoid dealing directly
> with stratum-1 servers, I assume this probably isn't as it should be.
> Is it, in fact, proper for a stratum-1 server to be registered as part
> of a pool?  Where -- if anywhere -- should I report a stratum-1 server
> found in a pool?  Should I consider doing something in my ntp.conf so
> as to avoid bothering a server from a pool if it happens to be in
> stratum 1?
> Rich Wales
> richw at richw.org, richwales at gmail.com

I wouldn't worry excessively about it!  If there is a stratum one server 
in the pool, it's there because the owner wanted it there.

What you should NOT do, is configure several of your machines to use it!
If you have ONE server querying that stratum 1 box, that server is a 
stratum two server and can serve time to your local network.

For that matter, you could set up your own stratum one server!  All it 
takes is a GPS Timing Receiver and a PC running Solaris or Linux and 
NTPD.  Net investment is $100-$300 for the timing receiver, cable, 
connectors and a PC that might otherwise be acting as a door stop or a 
paper weight.  Yes, that three year old PC that just isn't good enough 
for your desktop any longer will make a fine Stratum 1 NTP server!

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