IBM System Storage TS3500, Introduction And Planning Manual

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Table 65. Valid Loop IDs and their associated AL_PAs for Ultrium tape drives and 3592 tape drives in the IBM
System Storage TS3500 Tape Library (continued)
7-bit Loop ID
(decimal)
8-bit AL_PA
(hexadecimal)
7-bit Loop ID
(decimal)
8-bit AL_PA
(hexadecimal)
7-bit Loop ID
(decimal)
8-bit AL_PA
(hexadecimal)
38 X'AA' 81 X'54' 124 X'02'
39 X'A9' 82 X'53' 125 X'01'
40 X'A7' 83 X'52' 126 X'00'
41 X'A6' 84 X'51' 127 – –
42 X'A5' 85 X'4E' – – – –
LUN assignments
This section defines the logical unit number (LUN) for a Sequential Access device
(drive) and the Medium Changer device (library).
The logical unit number (LUN) for the Sequential Access device (the SCSI term for
a drive) is always LUN 0, and the LUN for the Medium Changer device (the SCSI
term for the library) is always LUN 1 (all other LUNs are invalid addresses). These
devices are compatible with the SCSI-2 or SCSI-3 standard. For information about
the SCSI commands for the tape drives, see the
IBM TotalStorage LTO Ultrium Tape
Drive SCSI Reference or IBM System Storage 3592 Tape Drive SCSI Reference . For
information about the SCSI commands for the library, see the IBM System Storage
TS3500 Tape Library SCSI Reference .
Note: The Medium Changer SCSI ID is the same as the SCSI ID for Drive 1, Frame
1. You can enable additional drives to optionally provide Medium Changer (LUN
1) addressing by configuring more than one logical library or by enabling
additional control paths (refer to the sections about configuring the library with
partitions or changing a control path in the
IBM System Storage TS3500 Tape Library
with ALMS Operator Guide ).
Using World Wide Names
This section discusses the World Wide Name (WWN) addresses that the TS3500
Tape Library assigns to drives. The WWN does not change when the drive is
swapped or replaced, and host parameters do not need to be changed or
reconfigured.
Normally, blocks of World Wide Name (WWN) addresses are assigned to
manufacturers by the IEEE Standards Committee, and are built into devices during
manufacture. In the case of the TS3500 Tape Library, however, the library assigns
World Wide Node Names and World Wide Port Names to the drives. This
technique is referred to as “library-centric world wide names.” Potential drive slots
are each assigned a WWN which does not change when a drive is swapped or
replaced.
In the TS3500 Tape Library, a WWN for a drive is implemented through an
algorithm that uses the frame serial number of the library and the drive's position
within the library. Only the last two digits change within the library. The
second-to-the-last digit represents the frame number (starting at 0 for Frame 1) and
the last digit is the drive row (starting at 1). The WWN of the drive is
location-dependent and not device-dependent. That is, each time that the drive is
reset or powered on, the library reestablishes the WWN so that a drive in frame x,
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IBM System Storage TS3500 Tape Library with ALMS: Introduction and Planning Guide