IBM Ultrium Gen 6, Installation And User Manual

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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 LTO-CM storage capacity of the LTO Ultrium 6 is 16320 bytes, LTO Ultrium 4
and 5 is 8160 bytes, and Ultrium 1, 2, and 3 is 4096 bytes.
Write-protect switch
The position of the write-protect switch on the tape cartridge determines whether
you can write to the tape.
See Chapter 4, “Using Ultrium media,” on page 43 for the location of the switch.
If possible, use your server's application software to write-protect your cartridges
(rather than manually setting the write-protect switch). This allows the server's
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 the switch is in the locked position, (solid red), data cannot be written to the
tape. If the switch is in the unlocked position (black void), data can be written to
the tape.
If you must manually set the write-protect switch, slide it left or right to the
desired position.
Capacity scaling
To control the capacity of the cartridge (for example, to obtain a faster seek time)
issue the SCSI command
SET CAPACITY
.
For information about this command, refer to the IBM TotalStorage LTO Ultrium
Tape DriveSCSI Reference in the IBM Support portal.
WORM (Write Once, Read Many) cartridge
Certain records-retention and data-security applications require a Write Once, Read
Many (WORM) method for storing data on tape. The LTO Ultrium generation 4, 5,
and 6 drives enable WORM support when a WORM tape cartridge is loaded into
the drive.
Because standard read/write media are incompatible with the WORM feature, a
specially formatted WORM tape cartridge is required. Each WORM cartridge has a
unique, worldwide cartridge identifier (WWCID), which is comprised of the
unique CM chip serial number and the unique tape media serial number. Ultrium
6 WORM cartridges are two-tone black and silvery-gray.
Chapter 4. Using Ultrium Media
45