User's Manual

Configuring and Operating the DLT4700 Mini-Library
DLT4000/DLT4500/DLT4700 Cartridge Tape Subsystem 5-7
5.4.2 Automatic Mode
This is the default or normal mode of the DLT4700 mini-library. This mode allows
the DLT4700 mini-library to load and unload cartridges as needed during backup
procedures.
When the user engages the Automatic Mode a SCSI ‘unload’ command is issued, not
only is the currently loaded cartridge unloaded from the drive and restored to its
position in the magazine, the next higher-numbered cartridge is loaded into the drive.
A SCSI ‘load’ command is unnecessary, except to load the lowest-numbered cartridge
upon inserting the magazine.
When you copy data to the tape, operations stop if one of the following happens:
• Storage capacity of the last tape cartridge is exceeded
• No tape cartridge is in the next sequential slot in the magazine
To lock the DLT4700 mini-library into its normal operating position in the enclosure,
but leave the receiver unlocked, set the Mode Select key to Automatic mode.
The following results of setting the Mode Select key to Automatic mode are:
• The OCP pushbuttons are enabled.
• SCSI media changer commands are enabled.
• Cartridges are sequentially loaded by the SCSI ‘unload’ command, but the lowest-
numbered cartridge is not automatically loaded upon magazine insertion.
Behavior in this mode is modified by the EEPROM parameters
ENALDRAUTOLD (1) and DISLDRAUTOLDMC (0), which enable both
sequential and random-access functionality.
5.4.3 Manual Mode
Automatic loading and unloading of cartridges does not occur in this mode. You must
press the Load/Unload button to move each cartridge. This mode is most useful for,
but not restricted to, copying specific files to or from tape. Basically, only the OCP
pushbuttons are enabled, as SCSI commands are disabled.
To lock the DLT4700 mini-library into the enclosure, set the Mode Select key to
Manual mode.
The following results of setting the Mode Select key to Manual mode are:
• The receiver is unlocked and can be opened.
• The OCP pushbuttons are enabled.