Sun Microsystems StorageTek T10000, Operator'S Manual

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T10000 Cartridges
30 T10000 Operator’s Guide • July 2008 Revision EA • 96174
Cleaning Cartridges
As the name implies, you would use these cleaning cartridges to clean a drive’s
read/write head up to 50 times. An attempt to use a cleaning cartridge beyond that
results in the tape drive rejecting the cleaning cartridge and posting an error message to
the host. You can identify these cleaning cartridges by a white leader access door
(see
FIGURE 1-4
).
Note – It is recommended that you clean the T10000B tape drive every ten full file
operations due to its higher linear density and capacity. This is three times more
frequent than with the T10000A tape drive.
Diagnostic Cartridges
These are a special-use version of the standard data cartridge with a special label. The
diagnostic cartridge is typically used by a service representative and most libraries
store one or more of these diagnostic cartridges.
(See “Diagnostic Cartridge Labels” on page 86 .)
Media Information Region
The T10000A/B tape drives use information recorded on each tape cartridge to reduce
access times and manage the useful life of the cartridge. This information is recorded in
the cartridge’s radio frequency identification (RFID) chip and at the beginning of tape
in an area known as the media information region (MIR). The information stored in the
RFID is a proper subset of the information stored in the MIR. The media information
falls into two categories: statistical counters and data pointers.
Statistical Counters
Statistical counters reflect the usage of the cartridge and includes read/write activity,
error activity, cumulative mounts, and other information about its use.
Data pointers
The data pointer information is basically a directory (map) used to locate the customer
(logical) data on the physical tape media. Since customer data is compressed and
written in drive controlled blocks on the tape, a map is needed to efficiently locate the
data after it is written. This map provides an index between customer data and the
physical block on the tape media. Once data is written the drive accesses this map to
optimize access to the customer data.
To locate/space to customer data, the logical object that identifies the block is translated
to the physical location on the tape media and the drive determines the quickest
method to read the block. If the block is some physical distance from the current
location, a calculation results in a high-speed locate to the block location and is
followed by a normal speed read.