[CentOS] NTP and hardware clock

Dag Wieers dag at wieers.com
Wed Oct 11 17:22:43 UTC 2006

On Wed, 11 Oct 2006, Kirk Bocek wrote:

> Kirk Bocek
> Dag Wieers wrote:
> > I had the following problem today. Because of a misconfigured 
> > network switch one system suddenly didn't have any network.
> > 
> > After a reboot (with the network still unavailable) NTPD refused to start. 
> > Most likely because the initial ntpdate failed to work. I find this 
> > troubling, because when the network was restored, NTPD could have resumed 
> > working (like I'd expect from a true daemon).
> > 
> > Now, what was more peculiar was that the hardware clock was completely 
> > off. I also had assumed that somehow the hardware clock was kept in sync, 
> > but now after rebooting without network, the system clock was skewed.
> > 
> > Is there some way to:
> > 
> >  + Make ntpd run, even when no ntp-server could be contacted
> >  + Make ntpd synchronise the hardware clock automatically
> > 
> > PS Yes, I know I can run ntpdate from cron or run hwclock to synchronize 
> > my hardware clock. But shouldn't this be part of the infrastructure 
> > (either ntpd or the initscripts) ?
> > 
> > Maybe this is useful to have fixed upstream, but I prefer to hear second 
> > opinions before trying to be smart :)
> Do you have the following lines in your /etc/ntp.conf:
> server     # local clock
> fudge stratum 10
> They identify your local clock as a low-stratum time server.

I fail to see how that is relevant, since the local clock is wrong after a 
reboot without network (so I rather not want to use it as a source :)) and 
ntpd is not even started because ntpdate fails.

But yes, I do have something like that (stratum 13 though).

Kind regards,
--   dag wieers,  dag at wieers.com,  http://dag.wieers.com/   --
[all I want is a warm bed and a kind word and unlimited power]

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