xntpd and new DST

The timezone updates/patches have nothing to do with "what time is it?". They have to do with "How do I display the time for you?".

NTP only updates the UTC clock. It has nothing to do with any timezone. It does not know the zone of the server or the client, and will provide no information about DST changes.

Your computer takes that clock and turns it into a displayed time. If you have the old zone info, then for US timezones that follow DST, the displayed time will be incorrect during the period in question.

Run these two lines on your system.

perl -le 'print scalar localtime 1175040000'

perl -le 'print scalar localtime 1143504000'

They show what your system will report for time at 00:00:00 March 28 UTC in 2006 and 2007.

If you are in a US timezone that honors DST, these should report times that are one hour apart on those days. If they report the same time, then you probably don't have the updates and it is assuming that DST is not in effect on either date.

For instance on a machine that is incorrect:

$ TZ=US/Pacific perl -le 'print scalar localtime 1175040000'

Tue Mar 27 16:00:00 2007

$ TZ=US/Pacific perl -le 'print scalar localtime 1143504000'

Mon Mar 27 16:00:00 2006

But with the updates:

$ TZ=US/Pacific perl -le 'print scalar localtime 1175040000'

Tue Mar 27 17:00:00 2007

--

Darren

Darren_Dunhama at 2007-7-8 1:52:35 >

You can also check what time your system will display in march 2007 by:

# zdump -v EST5EDT |grep 2007

EST5EDT Sun Mar 11 06:59:59 2007 UTC = Sun Mar 11 01:59:59 2007 EST isdst=0 gmtoff=-18000

EST5EDT Sun Mar 11 07:00:00 2007 UTC = Sun Mar 11 03:00:00 2007 EDT isdst=1 gmtoff=-14400

EST5EDT Sun Nov 4 05:59:59 2007 UTC = Sun Nov 4 01:59:59 2007 EDT isdst=1 gmtoff=-14400

EST5EDT Sun Nov 4 06:00:00 2007 UTC = Sun Nov 4 01:00:00 2007 EST isdst=0 gmtoff=-18000

cashdolla at 2007-7-8 1:52:35 >