[ntp:questions] Proposed NTP solution for a network

Richard B. Gilbert rgilbert88 at comcast.net
Wed Mar 4 22:00:25 UTC 2009

Augustine wrote:
> On Mar 3, 4:01 pm, "Richard B. Gilbert" <rgilber... at comcast.net>
> wrote:
>> NTP does this ONLY when the time is off by 128 milliseconds or more.  If
>> NTP is that far off, other than at startup, something is badly wrong
>> somewhere!
> The problem is that I've seen this in the silly reaction of different
> NTP versions and servers to the recent leap second, causing my systems
> to be stepped by 1s back and forth (see bug #1110).

OK, the leap second has proven to be a serious problem for the NTP 
network.  The recent leap second created some problems.  The previous 
leap second (2004?) was also a problem; it took something like 24 hours 
for the time to settle around the world.

I suspect that part of the problem is that the leap second is applied at 
the LOCAL midnight.  If everyone inserted the leap second at 00:00:00 
UTC, NTP would be perfectly happy with it but everyone else would be 

There may be a good solution to this.  My best solution is to have a 
"Leap Minute" every 240 years or so.  This would, however, create a much 
larger problem that occurred much less frequently.  Our 
great-great-great-great grandchildren could curse us and desecrate our 
graves if they could find them.

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