HP OpenVMS Systems

Timezones, and Standard and Daylight Time?

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The Question is:

 
Question:
What procedure should I use to set the following logicals permanently to the
following desired values
SYS$TIMEZONE_DAYLIGHT_SAVING = 0
SYS$TIMEZONE_DIFFERENTIAL = -28800
SYS$TIMEZONE_NAME = PST
SYS$TIMEZONE_RULE = PST8
 
Context:
I have already tried using the following 3 procedures
SYS$MANAGER:UCX$CONFIG.COM
SYS$MANAGER:UTC$TIME_SETUP.COM "" BOTH
SYS$MANAGER:NET$CONFIGURE.COM
 
But after a reboot I get
SYS$TIMEZONE_DAYLIGHT_SAVING = 1
SYS$TIMEZONE_DIFFERENTIAL = -25200
SYS$TIMEZONE_NAME = PST
SYS$TIMEZONE_RULE = PST8
 
However, on another Alpha that I tried the same on, it works
e.g. the values stick after a reboot.
 
It is like I'm missing something.
 
The big picture is that we want to synchronize time of some NT workstations
to that of an Alpha using NTP.
Special is that - for other reasons - we want to run the Alpha such that
OpenVMS does not perform automatic daylight saving time correction e.g. we
want to have time behave as it did on the VAX before automatic daylight
saving time correction was introduc
ed in VMS.
 
The problem with the above config. e.g. with SYS$TIME_DIFFERENTIAL=-25200,
is that NTP 'thinks' that VMS time is a daylight savings time time when it
fact it is not. And that it therefore compensates back when calculating UTC
which is sent to the NTP work
stations.
 
Both our customers and we hope that you can help in this matter.
Thank you very much in advance
 

The Answer is :

 
  Many political geographies participate in the switchovers between standard
  and daylight time, and many do not.  Many organizations participate, and
  many do not.
 
  Automatic daylight savings corrections are disabled by default on OpenVMS.
  (This prevents potential application problems that can arise when the system
  time is moved backward, and the incidence of odd timestamps.)  In other words,
  the daylight savings time change must be deliberately requested.
 
  The expected procedure used to configure (BOTH) is:
 
    SYS$MANAGER:UTC$TIME_SETUP.COM
 
  To alter between standard and daylight time, you must explicitly
  call the procedure:
 
    SYS$EXAMPLES:DAYLIGHT_SAVINGS.COM
 
  Information is available in the System Manager's Manual.
 
  Layered products may include additional timezone-related processing.  For
  instance, DECnet-Plus DECdtss support includes timezone management support.
 

  

     

     
answer written or last revised on ( 17-SEP-1999 )
     
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