The tricky part of the release upgrade is actually doing it. Remember for your own protection that IBM's documentation always has the last word, and the procedure IBM suggests should be followed even if it is in conflict with advice you get from other sources, including this book.
The very first step you need to perform is to back up your entire system. Do not omit anything. Here is what you need to do (xxx represents the name of your tape device):
End all subsystems from the system console to obtain a dedicated system.
ENDSBS SBS(*ALL) OPTION(*IMMED)
Save the system:
SAVSYS DEV(xxx) ENDOPT(*UNLOAD)
Save all nonsystem libraries:
SAVLIB LIB(*NONSYS) DEV(xxx) ENDOPT(*UNLOAD)
The SAV command operates across all the file systems supported by the iSeries. To save all the Integrated File System objects excluding DB2 (QSYS.LIB) and Office documents (QDLS):
SAV DEV('/QSYS.LIB/TAP01.DEVD') OBJ(('/*') ('/QSYS.LIB' *OMIT) ('/QDLS' *OMIT))
IBM has provided a short-cut method for backing up the entire system: From a command line, type GO SAVE and press Enter to access the Save menu. Select option 21 to carry out a complete save.
Throughout the backup process, you should clean your tape drive to make sure you are creating a good backup. Clean the tape drive before using each tape, even continuation tapes for the steps that require more than one. It is better to waste a little time now (by doing something that may be useless) than to waste hours later (because you lost data, and your backups were useless).
Chapter 6 contains an explanation of how you can save your system configuration. It is a very short procedure that can save you from trouble if something goes wrong.
The reason to save the system values is that sometimes new releases incorporate new system values. The existing system values should not be changed, but it is better to be safe than sorry.
Sometimes new releases make changes in the internal structure of subsystem descriptions, and sometimes they are changed without your knowledge. To save yourself headaches, you should print the description of all your subsystems and save the printouts.
First, run the Work with Subsystem Descriptions (WRKSBSD) command, as follows:
This command presents a list of all subsystem descriptions in existence. Then enter an option 5 (display) next to each one (do not press Enter yet, but do press Roll Up to display more pages, if any). When you are done entering a 5 next to all subsystem names, move the cursor to the command line and type the following:
Then press Enter. Option 5 runs the Display Subsystem Description (DSPSBSD) command for each subsystem. When combined with OUTPUT(*PRINT), the description is printed instead of displayed. Keep the listing in a safe place. It will be voluminous.
Get the manual IBM sent with the tapes and find where it explains how to install the new release. Keep this manual open next to you throughout the installation process. Check off the steps as you execute them.
If you do not have a dedicated system by now, end all subsystems to make sure that no one is using the system. You will already have a dedicated system if you backed up your entire system today, as indicated at the beginning of this section. If not, do:
ENDSBS SBS(*ALL) OPTION(*IMMED)
Now make sure you do not need to back up again! Has anyone been on the system and made any changes to the database or to the system?
Before you start the upgrade, you must run the Apply PTF (APYPTF) command to permanently apply all the PTFs you have temporarily applied to your current release.
Then you need to IPL the system:
APYPTF LICPGM(*ALL) APY(*PERM) DELAYED(*YES) PWRDWNSYS OPTION(*IMMED) RESTART(*YES)
This step can be skipped if you have plenty of available disk space. There is no way to tell for sure how much "plenty" is. When in doubt, perform this step.
Now follow IBM's instructions to install the new release of the operating system. Follow the instructions in IBM's book carefully.
You will have to mount tapes in a certain order. Be sure you mount the proper tape, and be sure to clean your tape drive after each tape.
Next, you need to load the PTFs included in the cumulative ("cume") tape IBM sent you with the new release (if one is available). Follow the instructions provided by IBM. This tape contains fixes for all the bugs that users have discovered in the operating system and system products.
You will use the Load PTF (LODPTF) command.
Now apply all the PTFs you have loaded from the cume tape. You will use the APYPTF command as indicated in the instructions provided by IBM. Then IPL your system again to make sure that all PTFs are applied successfully.
Your system is now running the new release of the operating system.
Compare the listings of system values and subsystems you obtained against the real thing to check system values and subsystem descriptions. Configuration objects should not have changed; if they have, you can run the Restore Configuration (RSTCFG) command if the changes introduced by the release upgrade are for the worse. In making this evaluation, always keep in mind that the release upgrade might have introduced changes to support new features not available in the previous release. Do not undo these changes by accident.
If you changed some system (QSYS) objects before the upgrade, your changes are gone. You will have to perform all your changes again.
Usually it is a better idea to create duplicates of QSYS objects and place them in a user library that you place at the top of the system portion of the library list, so that the system uses your copies instead of the original QSYS objects. In this case, be sure to delete your copies from your user library, make fresh copies from QSYS again (which will incorporate the new features or other changes they may have), and perform your changes on the duplicates.
Finally, if everything went OK, you can now make the system available for use. Depending on what changes you had to redo on system values or other settings, you may need to IPL the system to make sure all the changes are effective. It is a good idea to IPL the system once again just to be sure:
PWRDWNSYS OPTION(*IMMED) RESTART(*YES)