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CHAPTER
Power On and Off
This chapter explains steps to perform before removing a customer replaceable unit
(CRU).
Powering Off the System
Before you begin any removal or replacement procedure, you must halt the system
in an orderly manner. The procedure to use depends on whether your system is
working normally or not, as described in the next sections.
Caution -
booted, do not use the Stop-a keys to halt the system. Using the Stop-a keys to abort
program execution can damage data files.
When the System Is Working Normally
To halt your system when it is working normally:
1. Save all your work.
Consult your software documentation for instructions on ending a work session
and saving your files. If you do not save your work, you could lose it when you
switch off the power.
2. Return to the operating system environment.
When the operating system or any other standalone program has already
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