IBM TotalStorage Ultrium 3580 H23, Руководство по настройке и эксплуатации

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In addition to using LTO Ultrium 2 Tape Cartridges with up to 200 GB capacity,
the tape drive reads and writes to certified LTO Ultrium Tape Cartridges that have
capacities of 100, 50, 30, and 10 GB. If you want to control the capacity of the
cartridge (for example, if you want to limit the capacity to obtain a faster seek
time) you can do so by issuing the SCSI command SET CAPACITY. For
information about this command, refer to the IBM TotalStorage LTO Ultrium Tape
Drive SCSI Reference.
To ensure that your tape drive conforms to IBM’s specifications for reliability, use
only IBM LTO Ultrium Tape Cartridges. You may use other LTO-certified data
cartridges, but they may not meet the standards of reliability that are established
by IBM. The IBM TotalStorage LTO Ultrium 200 GB Data Cartridge cannot be
interchanged with the media used in other IBM non-LTO Ultrium tape products.
Data Cartridge
The IBM Ultrium 2 Data Cartridge is purple, and the Ultrium 1 Data Cartridge is
black. Both generations contain 1/2-inch, dual-coat, metal-particle tape. The
Ultrium 1 cartridge has a native data capacity of 100 GB (200 GB at 2:1
compression); the Ultrium 2 cartridge has a native data capacity of 200 GB (400 GB
at 2:1 compression).
When processing tape in the cartridges, the Ultrium Tape Drives use a linear,
serpentine recording format. The Ultrium 1 drive reads and writes data on 384
tracks, eight tracks at a time; the Ultrium 2 drive reads and writes data on 512
tracks, eight tracks at a time The first set of eight tracks is written from near the
beginning of the tape to near the end of the tape. The head then repositions to the
next set of eight tracks for the return pass. This process continues until all tracks
are written and the tape is full, or until all data is written.
Both generations of the IBM LTO Ultrium Data Cartridges include a Linear
Tape-Open Cartridge Memory (LTO-CM) chip (
1
in Figure 7 on page 25), that
contains information about the cartridge and the tape (such as the name of the
manufacturer that created the tape), as well as statistical information about the
cartridge’s use. The LTO-CM enhances the efficiency of the cartridge. For example,
the LTO-CM stores the end-of-data location which, when you next insert a
cartridge and issue the Write command, enables the drive to quickly locate the
recording area and begin recording. The LTO-CM also aids in determining the
reliability of the cartridge by storing data about its age, how many times it has
been loaded, and how many errors it has accumulated. Whenever you unload a
tape cartridge, the tape drive writes any pertinent information to the cartridge
memory. The storage capacity of the LTO-CM is 4096 bytes.
The cartridge door
2
protects the tape from contamination when the cartridge is
out of the drive. Behind the door, the tape is attached to a leader pin
3
. When
you insert the cartridge into the drive, a threading mechanism pulls the pin (and
tape) out of the cartridge, across the drive head, and onto a non-removable takeup
reel. The head can then read or write data from or to the tape.
The write-protect switch
4
prevents data from being written to the tape
cartridge. On the data cartridge, the switch is red; on the cleaning cartridge, the
switch is gray. The label area
5
provides a location for you to place a label. Affix
only a bar code label. When affixing a label, place it only in the recessed label area.
A label that extends outside of the recessed area can cause loading problems in the
internal drive or in the 3580 Ultrium 2 Tape Drive. The insertion guide
6
is a
large, notched area that prevents you from inserting the cartridge incorrectly.
26
IBM 3580 Ultrium Tape Drive Setup and Operator Guide