When you replace your software with the new release, by default the server keeps changes that you made to some IBM-supplied objects.
Certain job descriptions and subsystem descriptions are restored during the installation process. The installation process creates these libraries (if they do not already exist):
The system copies your current customized descriptions from library QSYS to library QINSYS. The descriptions are installed from the installation media into library QSYS. The system compares those values with the descriptions in QINSYS. If there are any differences, the system uses your customized value from QINSYS to update the QSYS version. If there are conflicts in certain values, the system uses the value from the installation media, and the conflicting value remains in QINSYS. QINMEDIA holds the description from the installation media. QINPRIOR holds the descriptions from the prior release level so that you can compare the current and previous release descriptions.
Use the PRTSYSINF command before you upgrade to have a copy of the IBM-supplied objects. After the upgrade you can change these objects back to the previous customization.
If you have made changes to any of the IBM-supplied descriptions shown in the following table, the system optionally keeps your changes.
| Job descriptions | Subsystem descriptions |
|---|---|
| QCTL (Controlling subsystem job description) | QBASE (Basic controlling) |
| QCTLIJBD (Controlling subsystem ICG job description) | QBATCH (Batch) |
| QESAUTON (Automatic problem notification) | QCMN (Communications) |
| QFSIOPWK (File server I/O processor) | QCTL (Controlling subsystem) |
| QMSF (Used by QPGMF job) | QINTER (Interactive) |
| QPDAUTOPAR (Used for automatic problem analysis) | QPGMR (Programmer) |
| QQQTEMPS (DB2® UDB for iSeries™ job description used by QSYSWRK) | QSNADS (Systems Network Architecture (SNA) Distribution) |
| QSPLERROR (Spooling error) | QSPL (Spooling subsystem) |
| QSTRUPJD (Auto start) | QSYSWRK (System subsystem) |
| QSYSWRK (System subsystem job description) | QUSRWRK (User subsystem) |
| QTMSNMP (Simple Network Management Protocol (SNMP) job description) | |
| QZMFEJBD (QSYSWRK autostart job entry) |