[ntp:questions] avoiding large steps (on time island)

Richard B. Gilbert rgilbert88 at comcast.net
Thu May 17 15:55:52 UTC 2007

seanjlangford at gmail.com wrote:
> I'm having some trouble with a 'time island' type configuration;  I
> have a number of ntp clients connecting to one ntp server using its
> local clock driver (  This network is isolated from the
> rest of the world, and for this application, having universally
> correct time is far less important than having 'node-relative'
> accurate time.  I have a problem scenario where the client starts
> *before* the server and misses the opportunity to do the one time sync
> to the server (ntp -g).  Then sometime after the server boots, the
> clients clocks make large steps to correct the difference (with a
> 'time reset' ntp log message).   This is causing hangs in our client
> application software as it uses software timers.  Is there a way to
> limit the size of a step? or spread it out over time more slowly?  I
> am aware of the -x flag, but would rather to continue to step, but in
> smaller sizes.
> Cheers
> Sean
> Client config:
> tinker panic 0
> logfile /var/log/ntpd.log
> driftfile /var/lib/ntp/drift
> server prefer
> fudge
> Server config:
> logfile /var/log/ntpd.log
> driftfile /var/lib/ntp/drift
> server iburst minpoll 4
> fudge stratum 10 prefer

The simplest thing to do would be to start the server before the client 
or just never shut the server down!

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