Re: Sync system time with RTC

On Tuesday, in article <7NJMf.118$JZ1.9328@xxxxxxxxxxxxxxx>
tog@xxxxxxxxx "The Other Guy" wrote:

Michael Sierchio wrote:
The Other Guy wrote:
Hi,

Is there any way to instruct FreeBSD to use the RTC instead of
maintaining an internal time reference?

I'm running FreeBSD in QEMU and the clock is falling behind by hours
each day.

man ntpd. man ntpdate.

I am actually using ntpd on the network, including on virtual systems
running under Qemu. This doesn't make any difference, I suspect due to
the rate the clocks vary. By the time ntpd does the initial check, the
clock is already out by more than the maximum amount ntpd will adjust for.

I was hoping there was a simple sysctl setting or another option to use
the RTC instead as this seems to be more reliable.

Not that I can see. It's possible to set a different tickrate in
kernel config but that might still be erratic when running qemu
and clock would then normally be a lot too fast which is probably
a worse situation.

Have you tried just repeatedly calling 'ntpd -q -g' to poll and exit
or 'ntpdate -b -t timeout server' ?

David

--
The Reply-To: is valid for at least 30 days after posting date
David Lord - david@xxxxxxxxxxxxxxxxxxxx
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