IBM RS/6000 7025 manual Data Cartridge Erasure, Tape Cartridge Data Capacity, Environments

Operating

in

Harsh

Environments

The 4-mm tape drive is ideally suited to

streaming operations, as opposed to tape

movement

operations

involving

multiple stop/starts and random

searches.

When

the

tape

is

used

for frequent stop and start

operations,

streaming

movement

is

beneficial

and

should be

used

whenever

possible.

This

can be accomplished by ensuring that

any save or restore operation is the only

active

operation performed by

a

device

connected

to

this

SCSI I/O controller.

Any tape that has been used outside the

ranges specified in the previous

table

for

extended

period

of

time

(50

passes in

40

hours of nonstop operation) should not be

used

as

an archival tape. Exposure to

the

environment will deteriorate the magnetic

and physical strength of the tape. Do

not

store important data on a tape that has

been used outside the specified ranges;

transfer

the

data to

a new

tape

for

relia

archiving.

4-mm	Data	Cartridge Erasure
Most	bulk	eraser	devices	do	not	have the	capability	to erase 4-mm data cartridges.
To properly erase an 4-mm				data		cartridge	with a bulk	eraser device, the erasure
rating must be			at least	2000	oersted.

The 4-mm tape drive erases residual data before writing new data on the data tape.

Tape Cartridge Data Capacity

The 4-mm tape cartridge capacity is defined as the amount of data that can be stored on the cartridge. The following variables affect the amount of data that can b stored on a tape cartridge:

Ÿ Size of the data file

Ÿ Number of file marks per file

Ÿ Compatibility mode (2GB or 4GB)

ŸMedia rewrites.

2-36IBM RS/6000 7025 F50 Series User's Guide