Admin Alert: Changing Your Mind When Loading Group PTFs

by Joe Hertvik

Most administrators are familiar with the standard PTF application process, where OS/400 PTFs are loaded on a partition and then applied during the next unattended IPL. But there may be times when you need to skip IPL PTF application because of a bad PTF or a tight IPL schedule. Is there a way to back out of IPL PTF processing and delay PTF application for another time?

The answer is yes. IBM gives you a green-screen option for loading PTFs onto your system and then picking and choosing which PTFs to apply and which PTFs to skip during an IPL. It's a relatively easy procedure that involves nothing more than the judicious application of the Apply Program Temporary Fix command (APYPTF).

This technique is best used when applying large groups of PTFs to your system, such as may happen when you are loading group PTFs or a cumulative PTF package. With a large PTF order, you traditionally use option 8, Install Program Temporary Fix Package, from the Program Temporary Fix menu to load the PTFs onto your system and mark them for application. The Program Temporary Fix menu is accessed through the following Go to Menu command (GO):

GO MENU(PTF)

Option 8 loads the group or cumulative PTFs onto your system and marks them for application during the next IPL. Each PTF that is loaded onto your system has an IPL action flag that is set to 'Yes', and the IPL process reads those flags to determine which PTFs to apply. You can view loaded PTFs and their associated IPL action flags by using option 5, Display a program temporary fix, from the Program Temporary Fix menu. You can also see the same information by using the Display Program Temporary Fix command (DSPPTF).

If you change your mind about applying the entire PTF group or an individual PTF to your system, it's fairly easy to modify that flag so that your target PTF (or PTFs) remains loaded on your system but it is not applied during IPL. You may want to do this to bypass applying a potentially bad PTF or to defer PTF application for a later IPL. You do this by using the APYPTF command in the following ways.

To turn off the IPL action flag for one or more specific PTFs that are scheduled to be applied to a single product, you can run APYPTF this way:

APYPTF LICPGM(licensed_program_number) SELECT(PTF_number)
      DELAYED(*YES) APY(*TEMP) IPLAPY(*NO)

The key to making this command work lies in setting the IPL apply options parameter (IPLAPY) to *NO. IPLAPY specifies which action to perform for these PTFs at the next unattended IPL. Setting it to *NO cancels any previous requests to apply these PTFs at IPL time by turning off the PTF's IPL action flag. This means that the PTFs will remain loaded on the system but they will not be applied during the next IPL.

You can also use APYPTF to turn off the IPL action flag for multiple PTFs that are scheduled to be applied to the same OS/400 licensed product. If you want to forego PTF application for several individual PTFs that will be applied against different licensed products, you must enter one APYPTF command for each product's PTFs that you want to turn off the IPL action flag off for.

If you want to turn off the IPL action flags for all PTFs that are waiting to be applied, you would run the APYPTF command like this:

APYPTF LICPGM(*ALL) APY(*TEMP) DELAYED(*YES) IPLAPY(*NO)

And the system will skip PTF application altogether during its next IPL.

To turn the IPL action flags back on, you simply reverse the process by running the APYPTF commands in the following ways:

If you want to turn the IPL action flag back on for a specific PTF that is already loaded on the system, you would run APYPTF this way.

APYPTF LICPGM(licensed_program_number) SELECT(PTF_number)
      DELAYED(*YES) APY(*TEMP) IPLAPY(*YES)

And setting the IPLAPY parameter to *YES changes the IPL action flag back to Yes for these unapplied PTFs.

To turn on the IPL action flag for all loaded but unapplied PTFs on your system, run the APYPTF command this way:

So this is the simple way to change your mind and bypass PTF application, even after you have loaded group PTFs onto your system. You may not use this technique often, but it certainly comes in handy when you need it.