[ntp:questions] Local Time

Richard B. gilbert rgilbert88 at comcast.net
Thu Mar 15 18:48:39 UTC 2007


Paul.Croome at softwareag.com wrote:
> To re-phrase and amplify Steve's comments:
> 
> Let's get back to basic principles. NTP propagates time through a
> pyramid of
> servers that are interconnected via a jittery network.
> 
> If you feed in UTC at the top of the pyramid, then all the NTP servers
> tick
> to the UTC clock. This is generally considered to be the most common
> scenario.
> 
> If you use a computer configured with LCL-CLK as the stratum-1 server
> at the top
> of the pyramid, then all the NTP servers synchronize to that LCL-CLK.
> Questions
> relating to this scenario pop up often in this newsgroup.
> 
> But there's nothing at all in NTP that prevents you from feeding in
> your own
> flavour of time at the top of the pyramid. It's your decision. The
> only conditions
> are: firstly, your timesource should run at a rate close to 1 sec/sec;
> secondly,
> you must be absolutely certain that your NTP pyramid will never come
> into contact
> with other NTP servers that are running UTC (or vice versa; NTP
> servers that are
> running UTC should never come into contact with your 'contaminated'
> time).
> 
> Statements like "NTP runs UTC - period" require qualification.
> 
> Paul
> 
> 
> 

NTP "BELIEVES" that the time it is getting is UTC.  If you feed it 
Eastern Slobovia Daylight Savings Time, that's what you will get.  This 
is generally a REALLY BAD IDEA but someone might want to do it for 
reasons I have trouble imagining.  If you do it, be careful to NEVER 
connect your network to a public network.




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