Adjusting time on a secured FreeBSD machine.

David Magda dmagda at ee.ryerson.ca
Wed Feb 2 16:05:32 PST 2005


On Feb 2, 2005, at 16:56, Eli K. Breen wrote:

> Lastly this machine is in production and cannot be rebooted.

Stop the NTP daemon and restart it so that it uses the "-x" option. 
 From ntpd(8):

>      -x      Normally, the time is slewed if the offset is less than 
> the step
>              threshold, which is 128 ms by default, and stepped if 
> above the
>              threshold.  This option forces the time to be slewed in 
> all
>              cases.  If the step threshold is set to zero, all offsets 
> are
>              stepped, regardless of value and regardless of the -x 
> option.  In
>              general, this is not a good idea, as it bypasses the 
> clock state
>              machine which is designed to cope with large time and 
> frequency
>              errors Note: Since the slew rate is limited to 0.5 ms/s, 
> each
>              second of adjustment requires an amortization interval of 
> 2000 s.
>              Thus, an adjustment of many seconds can take hours or 
> days to
>              amortize.  This option can be used with the -q option.

When you restart it make sure it's done with all the CLI options it has 
now, with the addition of the "-x".



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