[ntp:questions] Re: ntp client over satellite and no CMOS battery

David J Taylor david-taylor at blueyonder.co.not-this-bit.nor-this-part.uk.invalid
Tue Sep 13 12:37:30 UTC 2005


Danny Mayer wrote:
> David J Taylor wrote:
>>
>> The Windows NT 4 system was restarted recently following a power
>> glitch after being up for about a year continuous, and the CMOS had
>> drifted quite a bit.  Normally, stopping NTP would update the CMOS
>> time, but if the power stops (and no UPS here) the CMOS will have
>> been running at its own rate since system startup.
>>
>
> There is code in NTP to write to the CMOS clock on Windows. See the
> following comment in ports/winnt/ntpd/nt_clockstuff.c:
>
>   /* read the current system time, and write it back to
>            force CMOS update: */
>       /************ Added back in 2003-01-26 *****************/
>
>
> Depending when your binary was built you may not have it in your
> version. Time to upgrade?
>
>
> Danny

I already replied to this - is the newsgroup <--> list gateway slow?

In case you didn't get the reply, yes, this code was added at my request, 
but doesn't help in a powerfail situation such as I encountered.  What's 
needed is a continual update of the CMOS (once an hour or once a day), but 
you can't do that (I think) without setting the system time, which may 
cause a 10ms or 15ms step.  Setting the RTC directly would do the job.

Cheers,
David 





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