Initial time zone setting

There is no shipped default value for the QTIMZON system value. You can set this system value in System i® Navigator and from the IPL Options display during an attended initial program load (IPL).

To determine the initial value for the QTIMZON system value, the operating system performs the following actions:

1. The system attempts to retrieve the time zone from the QWCTIMZON data area.

   During the IPL of an IBM i software upgrade, the operating system looks for a data area named QWCTIMZON in the QSYS library. To create the data area before installation, see Setting the time zone before upgrading to IBM i V5R3, or later. If the data area is found, the following steps are taken:

   1. The system attempts to find a time zone description object whose name matches the time zone description object named in the data area. If this step fails, the system proceeds to 1.b.
   2. The system attempts to find a time zone description object whose name is derived from the offset specified in the data area.

      This name consists of the letter Q, followed by an N if the offset is negative, or a P if the offset is positive; then it is followed by the offset hours and minutes; and finally by the letters UTCS. For example, if the offset specified in the data area is -06:00, the operating system attempts to find a time zone description named QN0600UTCS. Note that if the offset is zero, the character representing the sign (N or P) is omitted, and the name used is Q0000UTC. If this step fails, the system proceeds to 1.c.

   3. The system attempts to create a new time zone description whose name and offset match the information specified in the data area.

      This time zone description does not support DST. For example, if the data area specified is -05:15MYTIMEZONE, the operating system attempts to create a time zone description named MYTIMEZONE with an offset of negative five hours and 15 minutes. If this step fails, the system proceeds to 2.

2. The system attempts to retrieve the time zone from the offset from UTC (QUTCOFFSET) system value.
   If the data area QWCTIMZON does not exist, or if the preceding steps fail, the operating system attempts to use the value specified in the QUTCOFFSET system value. The following steps are performed:

   1. The system attempts to find a time zone description object whose name is derived from the offset specified in the QUTCOFFSET system value. See 1.b for information about how this name is derived. If this step fails, the system proceeds to 2.b.
   2. The system attempts to create a new time zone description whose name was derived in the previous step 2.a and whose offset matches the information specified in the QUTCOFFSET system value. This time zone description does not support daylight saving time.

If all of the preceding steps fail, the QTIMZON system value is not set. In System i Navigator, the Time Zone field is blank, and in the character-based interface, the time zone parameter is set to *N (not available). In addition, the offset from Coordinated Universal Time (UTC) value is set to 0. Then, the system's local system time is set to the current UTC.