Lukas Beeler's IT Blog

If you’re using i5/OS V5R3 or V5R4, you can use time zones. If you aren’t using V5R3 or V5R4 yet, you should upgrade ASAP as support for V5R2 and earlier has been retired.

The system value QTIMZON specifies the timezone to be used, but which one of the following four is the right one:

QP0100CET
QP0100CET2
QP0100CET3
QP0100CET4

You can’t really tell from the names, but CET4 is the right one, it changes the clock at 3 in the morning, CET2 changes the clock at 2 in the morning, and CET doesn’t have daylight savings time at all.

Now, the question is where is this documented? I didn’t find it. I used CET2 at first, which seemed to work – but an IBM technician told me the difference between the different CET values.