[VoiceOps] DST handling

Jonathan Thurman jonathan at thurmantech.com
Thu Nov 5 17:34:52 EST 2009


On Thu, Nov 5, 2009 at 3:16 PM, David Hiers <hiersd at gmail.com> wrote:
> I thought that ntp doesn't know or care about DST.  It works in UTC,
> and the OS is responsible for any DST adjustment it wants to make.
>
> If you're an hour (3600 seconds) off in NTP, and it takes 2000 seconds
> to adjust for every second you are off, it'll take 7200000 seconds to
> get back on track, which is about 83 days.  Seems kinda long...

On most NTP implementations that I have worked with, the service will
not make jumps above a certain threshold (like more than 5 minutes
off).  It is the responsibility of the operator to get the clock in
sync to start with, then NTP will adjust for the natural drift.

Thanks for the correction Peter, I should have said UTC, not GMT.  All
of our hardware clocks use UTC, and then the OS/reporting/etc adjusts
to make the user feel warm and fuzzy.

-Jonathan


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