PTFs are applied temporarily by default. The system keeps two versions of the system objects affected by PTFs. The old one is in IPL area A and the new one is in area B. Because the system has the two versions, you can go back to a status prior to the application of a particular PTF.
When you apply a PTF permanently, however, the system replaces the original object with the new one. You cannot go back. If you apply a PTF temporarily and then decide to apply it permanently, the objects that were in IPL area B are copied to area A, and the space in area B is freed. Applying PTFs permanently gives you additional disk space.
Before applying PTFs permanently, you can remove them using the Remove PTF (RMVPTF) command that is discussed next. Make sure that the PTFs you have applied temporarily are, in fact, working before you apply them permanently. Sometimes IBM issues PTFs that do more damage than good. These PTFs are reported in the HIPER PTF packages as "PTFs in error."
If you think you are ready to apply PTFs permanently, you can use the DSPPTF to find out which PTFs have an "applied temporarily" status. You must apply these PTFs permanently (either all or some, as you decide). Armed with this information, you can run the Apply PTF (APYPTF) command, as follows:
APYPTF LICPGM(...) SELECT(...) APY(*PERM) DELAYED(*YES) +IPLAPY(*YES *APYPERM)
In the LICPGM parameter, enter the licensed program number fixed by the PTFs you are going to apply permanently. For example, use 5738SS1 for i5/OS.
The SELECT parameter can have a list of up to 50 PTF numbers you want to apply, or you can enter *ALL if you prefer to apply all PTFs for the licensed program number indicated in the LICPGM parameter.
DELAYED(*YES) IPLAPY(*YES *APYPERM) means that the application of the PTFs will be delayed until the next unattended IPL. At that time, the system will apply all selected PTFs permanently.