[ntp:questions] Synchronizing against a free-running server

David Woolley david at ex.djwhome.demon.invalid
Mon Apr 15 10:23:04 UTC 2013

detha wrote:
> We have been trying to convince ntpd to synchronize with a free-running
> windows server (why one would want to do this is another question, suffice
> to say there are political reasons).

Is this w32time?  w32time will send a true root dispersion, which will 
eventually disqualify the server.  You will probably need to run the 
real reference ntpd with a local clock pseudo driver (something not 
otherwise recommended).

In general, though, you will need to provide the ntpq rv output for the 
rejected server's association, to see why it is being rejected.

> However I have not been able to convince it (neither 4.2.6p2 on debian nor
> 4.2.4p8 on centos) to do this. The moment the windows server is set to
> sync to anything (pool.ntp.org, some other server, ...) it works. But
> as long at the server advertises itself as 'stratum 1, .LOCL.', ntpd seems

It is bad practice to use stratum one for the bogus local clock driver. 
  If there is another valid method of disciplining the clock, a lowish 
stratum number is OK.  If it is free-running, the stratum should be set 
as high as possile subject to being acceptable to all of its clients, so 
that it cannot accidentally propagate very far.

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