[ntp:questions] Re: Hardware clock fails to update.

Richard B. Gilbert rgilbert88 at comcast.net
Thu Aug 3 16:15:16 UTC 2006

Frans Grotepass wrote:

> Our embedded system syncs with the server via NTP. The kernel (2.6.9) has RTC 
> set to UTC. When the system boots up, the hardware clock is off by 7200 
> seconds. When NTP syncs, the system time is set correctly and the system runs 
> synced for a decent while (2 hours). The system is then powered down and 
> restarted. Upon restarting, the clock returns to its 7200 second offset. 
> Various internet searches pointed to the fact that hardware clock syncing 
> being placed under the responsibility of ntp. Is this really the case? If so, 
> how can I check that NTP tries to update the hardware clock? 
> Best regards,
> Frans

I don't recall any NTP documentation that says the ntpd sets the 
hardware clock.  AFAIK, this is something the operating system does at 
such times as the designers thought appropriate.  I think that most do 
so when shutting down!  If your O/S does not set the hardware clock, 
perhaps you should have your application do so.

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