Table of content

Introduction

PTF is an update provided by IBM to correct a specific bug or add a new function to the software or the hardware. PTF can be handled one at a time (Single/Individual) or in groups (Group, Cumulative, Technology Refresh).

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Cumulative PTF packages (CUM) contain fixes for all LPPs. CUMs are heavily tested and has the lowest level of risk

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When applying PTFs

PTF packaging

An application of a PTF may, add objects to the system, replace multiple objects or remediate a problem by running a specific program.

When downloading the PTF package, it contains a SAVF + Cover letter. Once loaded, cover letters live in QGPL/QAPZCOVER:

• Cover letter has the same name as the PTF number but preceded with the letter ‘Q’
• If a new function is provided, the cover letter will describe how to enable the function (like changing a system value or restarting a service)

Temporary and Permanent PTF

• Temporarily applied PTF can be unapplied or removed

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PTFs that have been Temporarily applied for some time (usually long enough to prove that they aren’t defective) are usually Permanently applied to save disk space

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• Permanently applied PTF may be removed in only two ways:
  • Restore the system to a point prior to the PTF’s application
  • Get a new PTF from IBM that “undoes” the PTF that needs to be uninstalled (this only occurs with defective PTF)

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Prerequisite and co-requisite: if a PTF is being permanently applied, prerequisite PTF must also be also permanently applied

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Code bases

In order to understand the PTF application, we must understand the 3 code bases of IBM i system.