A system shutdown does not imply turning off power to the computer hardware. Instead, system shutdown means stopping the computer's operating system. Stopping system activity makes the computer inaccessible to users. You would need to shut down the system for maintenance, for a physical move, for changing the system configuration, or for security reasons.
If done properly, a shutdown preserves all system and user files. Before the shutdown occurs, backlogged reports can be printed, or they can be saved to tape and replaced when the system is running again.
The shutdown procedure usually consists of several steps, including the following:
telling users well in advance of a planned shutdown
warning users a few minutes before the shutdown
preventing anyone from starting a new job or session, or
printing new reports
clearing the backlog of reports before the shutdown (This step is unnecessary unless you need the space that these reports are using.)
answering any console requests
shutting open communication lines
aborting remaining jobs and sessions
entering the =SHUTDOWN command
The next several sections describe procedures associated with shutting down a system. Read through the remainder of this chapter before attempting a shutdown based on these instructions. Become familiar with the commands and options used in each process. Examine the processes for areas that you may need to customize for your system.
