Quantum DLT 2000 Handbook page 47

ical system administrator running a network backup application, more
capacity per cartridge means less need to swap cartridges.
More Reliable
While we were researching this book, we talked to end users and
network managers. Over and over again, they told us that they had
switched to DLTtape backup because the systems they had been
using just weren't reliable enough anymore. Under the pressure of
backing up big networks, 4mm and 8mm solutions just don't cut it.
This from the people whose necks are on the line when systems fail.
They say things like "too many midnight calls," or "every once in
a while an 8mm drive would go bang," or "our old 4mm drives
could not handle it." So, customers want DLTtape technology
because it is more reliable than any other backup technology.
Heavy Duty
Most drive makers base their performance and reliability figures on
drive utilization (duty cycle) as low as 10 percent. That means that
in a 7x24 operation, other drive makers base reliability figures on as
little as 2.5 hours of use during every 24-hour period. At Quantum,
we have traditionally calculated our reliability figures based on 100
percent usage. In fact, even at 100 percent duty-cycle, DLTtape dri-
ves are rated at up to 250,000 hours Mean Time Between Failures
(MTBF). Even when compared to a competing drive offering the
same MTBF, DLTtape drives are the clear winner, because we have
calculated MTBF assuming 100 percent usage. In practice, few dri-
ves will actually be subjected to non-stop operation. But, it's nice to
know you could run your DLTtape drive continuously if you had
to, without the worry of premature failure or data loss. (See
Chapter 5 for a complete discussion of DLTtape system reliability.)
Economy
Because DLTtape technology started life as a proprietary technolo-
gy, and because its market is primarily in the midrange and high-
QUANTUM DLTtape HANDBOOK 4.5