[VoiceOps] DST handling

[Peter Beckman]

On Thu, 5 Nov 2009, Dan Young wrote:

> On Thu, Nov 5, 2009 at 1:03 PM, Peter Beckman <beckman at angryox.com> wrote:
>>  In discussing time, one of my providers avoids syncing their servers to
>>  the correct time on an ongoing basis (i.e. with ntpd), with the argument
>>  that if they sync during calls, billing would be wrong.  Some of there
>>  servers therefore skew a LOT, and sometimes their call servers can be off
>>  the real time by _HOURS_ (I suspect this is due to running Asterisk on VMs
>>  which are notoriously bad at keeping time).  I've griped about it, but
>>  they say they only sync the time when there are no calls at midnight,
>>  which never happens.
>
> I'm sure this isn't news to you, but... By default, ntpd will not snap
> to a new time, but rather slew slowly towards the correct time.
>
> How slowly? man 8 ntpd:
> "about 2,000 s for each second the clock is outside the acceptable range."

  Oh, _I_ know that.  I've tried to explain to them why this would be a good
  thing.  Then again, I'm not sure how fast ntp can react to bad time skew
  due to Virtual Machine kernel timing issues, might take a lot of trial and
  error to get it right.

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Peter Beckman                                                  Internet Guy
beckman at angryox.com                                 http://www.angryox.com/
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