IBM TotalStorage 3580 L33, Setup, Operator, And Service Manual

Page: 43 / 143

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 Drive SCSI Reference .
WORM (Write Once, Read Many)
Certain records retention and data security applications require a Write Once, Read
Many (WORM) method for storing data on tape. To meet this data storage
requirement, a new WORM feature has been made available on IBM LTO Ultrium
generation 3 drives. The WORM feature can be enabled by upgrading to
WORM-capable drive firmware and using a special WORM tape cartridge (see
“WORM Media”).
No physical hardware changes are required to make Ultrium 3 drives compatible
with the WORM feature; however, appropriate WORM-capable drive firmware
must be installed. See “Requirements” on page 26 for minimum drive firmware
requirements.
WORM Media
Because standard read/write media are incompatible with the WORM feature, a
specially formatted WORM tape cartridge (see Figure 9) is required. Each WORM
cartridge has a unique, worldwide cartridge identifier (WWCID), which comprises
the unique CM chip serial number and the unique tape media serial number. See
“Ordering Media Supplies” on page 42 for information on how to choose and
purchase the appropriate WORM tape cartridges for your library.
Data Security on WORM Media
Certain built-in security measures help ensure that the data written on a WORM
cartridge does not become compromised, for example:
v
The format of an IBM Ultrium 3 400 GB WORM Tape Cartridge is unlike that of
standard read/write media. This unique format prevents a drive that lacks
WORM-capable firmware from writing on a WORM tape cartridge.
v When the drive senses a WORM cartridge, the firmware prohibits the changing
or altering of user data already written on the tape. The firmware keeps track of
the last appendable point on the tape.
WORM Media Errors
The following conditions cause WORM media errors to occur:
a66ug050
Figure 9. Ultrium 3 WORM Tape Cartridge
Using Ultrium Media
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