This chapter describes the processes for handling the backup media. The
subjects include:
Preparing the Backup Device
Replying to a Media Request
Automatically Assigning Devices
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 | NOTE:
Instructions for using backup devices in this chapter are general procedures
that apply to most devices. Your devices may operate differently. Refer to
the documentation for each device for exact instructions and additional
information. |
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Unless your backup devices are configured to be automatically allocated,
when a user (or a user's program) needs to use a backup device, you see
a media request at the console. For example:
?16:04/#S37/23/LDEV# FOR "T" ON MEDIA (NUM)?
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The media request asks you to assign an LDEV number to the file named in
the request. This process is called allocating the device. The request
above asks you to assign a logical device to the file T.
It tells you the time it arrived (16:04 in the example above), the
job or session that sent it (#S37 in the example above), and the
process identification number (called the PIN) of the program or command
that sent the request (23 in the example).
Depending upon your system configuration, the system may or may not
answer media requests automatically. Refer to "Automatically Assigning
Devices" later in this chapter. If it does, you need only to prepare
the backup device for use. If the system does not answer media requests
automatically, you must prepare the backup device and reply as explained
in "Replying to a Media Request," below.