It's just 4 weeks until the USA changes clocks. Daylight Saving Time (DST) starts on March 8, 2015. The clock is turned forward one hour at 2 am. In Germany we change 3 weeks later, on March 29.
That is it is time to plan for that change. A year ago I had a blog entry for the time change, that I want to re-post today:
With the z/VSE IPL commands SET ZONEDEF and SET ZONEBDY you can switch between standard and daylight local times without changing the IPL startup procedure each time. However, you have to IPL the system in order to switch to the new time zone, see the z/VSE System Control Statements for details. That book is here.
A local time change forward has normally no effect on subsystem operation. It may have an impact on accounting, however.
A local time change backwards could affect subsystems and accounting routines more severely.
Therefore I recommend to IPL the z/VSE system for any time changes.
There is also
a Technote on "Daylight Saving Time changes effect on CICS". The Technote is here.
some information about DST in the z/VSE Hints & Tips, see section "System Date and Time".
This book is on our documentation page - here.