Operating instructions

SEPTEMBER 2005 MAGNUM 1X7 LTO AUTOLOADER
3-7
UNDERSTANDING THE CARTRIDGE INVENTORY
SCSI Element Reservation
Using the RESERVE (16h or 56h) command, an initiator can either reserve the
entire autoloader as a unit or specific elements for its exclusive use. The
autoloader uses three fields to indicate element reservation by an initiator:
Reserved The Reserved flag indicates whether the element is reserved by an
initiator, as follows:
0 – The element is not reserved
1 – The element is reserved
Host ID The Host ID field contains the SCSI ID of the initiator that reserved
the element.
Reservation ID The Reservation ID field contains the reservation ID as set in
the RESERVE command.
Note: When the autoloader is reset, all reservation information is cleared. For
more information about the RESERVE command, see Chapter 20.
Tape Drive Accessible
The Tape Drive Accessible flag indicates whether the tape drive is empty, a
cartridge is loaded in the tape drive, or the cartridge is ejected, as follows:
0 – A cartridge may be loaded in the drive
1 – The drive is empty, or the cartridge is unloaded or ejected and ready to be
picked
This flag is set to 0 when the autoloader loads a cartridge in the tape drive and
after the autoloader is reset or the cartridge access port door is opened.
This flag is set to 1 when the autoloader detects that the tape drive is
accessible. The autoloader can detect that the drive is accessible after a move
operation, after a cartridge scan operation, or when the tape drive notifies the
autoloader that it is accessible.
Cartridge Pick and Put Retry Counts
The Cartridge Pick Retry Counts and Cartridge Put Retry Counts fields
indicate the total number of pick/put operation retries for each element
location. Note that the pick from one element location and put to another are
accomplished in a single motion. These fields are cleared when the autoloader
is reset.