[ntp:questions] Lep seconds

marknmbox-88 at yahoo.com marknmbox-88 at yahoo.com
Thu Jan 3 23:23:05 UTC 2008

Unruh - thanks for responding.  You are the only one
who did.  

I certainly did not mean to disparage NTP time.  I
have spec'ed that it be used on our system.  Where I
run into problems is when a leap second occurs. 
According to everything I've read when  NTP signals
the operating system that the second is occurring it
also outputs time.  It uses the POSIX standard method
- duplicate a second (or in some cases stretch the
last second).  This causes confusion when a time
sample is taken before the leap second and one during
the leap second.  The UTC standard (which only
addresses ascii time representations) actually counts
the second 0..60 rather than 0..59.

At this point I am obligated to use UTC and NTP.

Tht missing second is causing me to get a lot of heat.
 Does anyone know of a way to get NTP to count the
leap second rather than to delete it?  Or am I missing
the point.

>I don't want to step on anyones toes but I am getting
>a lot of heat over using a POSIX compliant ntp re
>seconds.  The 1 second error inserted can cause a lot
>of trouble.

Exactly what heat are you getting and what trouble is
it causing you?
Perhaps if you tell us the problem rather than your
solution, we could come
up with a solution.

>I now that the Olsen mod changes most Unix/Linux time
>processing to handle the leap second in a
>theoretically correct manner rather than being POSIX

I have no idea what "a theoretically correct manner "
is. The Posix IS a
theoretically correct manner. 

>compliant.  Is there a similar mod for NTP.  I am
>hoping that there is a mod that will cause NTP to
>supply theoretical UTC (even if it is not ascci).

NTP DOES supply both theoretical and practical UTC. 

I think what you are worried about is that you want
your system to provide
something like TIA-- Atomic time-- which has no leap
seconds. I believe the
Olsen mods have your system clock run on atomic time
and then use the
leapsecond file and the zoneinfo file for your region
to translate that to
your local time.

You could just set up ntp to add 33 sec to its time,
and you would have
atomic time.

>                            Mark

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