IBM LTO Ultrium 4, Installation And User Manual

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Each generation of data cartridge is identified by case color, native data capacity,
recording format and nominal cartridge life.
Data cartridge Case color Native data
capacity Recording format* Nominal cartridge life
(load/unload cycles)
Ultrium 4 Green 800 GB (1600 GB at
2:1 compression) Reads and writes data on 896
tracks, sixteen tracks at a time. 20,000
Ultrium 3 Slate Blue 400 GB (800 GB at
2:1 compression) Reads and writes data on 704
tracks, sixteen tracks at a time 20,000
Ultrium 2 Purple 200 GB (400 GB at
2:1 compression) Reads and writes data on 512
tracks, eight tracks at a time 10,000
Ultrium 1 Black 100 GB (200 GB at
2:1 compression) Reads and writes data on 384
tracks, eight tracks at a time 5,000
* The first set of tracks (sixteen for Ultrium 4 and 3; eight for Ultrium 2 and 1) 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 tracks for the return pass. This
process continues until all tracks are written and the cartridge is full, or until all data is written.
Cartridge Memory chip (LTO-CM)
All generations of the LTO Ultrium Data Cartridges include a Linear Tape-Open
Cartridge Memory (LTO-CM) chip (
1
in Figure 7 on page 37), 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 use. The LTO-CM enhances the efficiency of the cartridge. For example,
the LTO-CM stores the end-of-data location which, when the next time this
cartridge is inserted and the WRITE command is issued, 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 a
tape cartridge is unloaded, the tape drive writes any pertinent information to the
cartridge memory.
The storage capacity of the LTO Generation 4 LTO-CM is 8160 bytes. LTO
Generations 1, 2, and 3 have an LTO-CM capacity of 4096 bytes.
Write-protect switch
The position of the write-protect switch on the tape cartridge (see
4
in Figure 7
on page 37) determines whether you can write to the tape. If the switch is set to:
v
The locked position (solid red), data cannot be written to the tape.
v
The unlocked position (black void), data can be written to the tape.
If possible, use your server application software to write-protect your cartridges
(rather than manually setting the write-protect switch). This allows the server
software to identify a cartridge that no longer contains current data and is eligible
to become a scratch (blank) data cartridge. Do not write-protect scratch (blank)
cartridges; the tape drive will not be able to write new data to them.
If you must manually set the write-protect switch, slide it left or right to the
desired position.
38
LTO Ultrium 4 Half High Tape Drive