LTO 8 Type M cartridge (M8)
The LTO program introduced a new capability with LTO 8 tape drives: the ability
to write 9 TB (native) on a brand new LTO Ultrium 7 cartridge instead of 6 TB
(native) as specified by the LTO 7 format. Such a cartridge is called an LTO 7
initialized LTO 8 Type M cartridge. These LTO 8 Type M cartridges are identifiable
by using an automation barcode label ending with the last 2 characters M8.
Hereafter, these cartridges will be referred to as L8, M8, and L7, respectively.
Only new, unused LTO Ultrium 7 cartridges can be initialized as M8 cartridges.
Once a cartridge is initialized as M8, it cannot be changed back to L7. Initialized
M8 cartridges can only be written and read in an LTO 8 tape drive; LTO7 tape
drives cannot read initialized M8 cartridges.
M8 cartridges can be purchased as either pre-initialized (also referred to as
"labeled and initialized") M8 data cartridges or un-initialized M8 data cartridges
(M8 WORM cartridges are not supported). For either option, the barcode label is
included; however, the un-initialized M8 data cartridge must first be initialized in
tape libraries that support the automatic initialization of un-initialized M8
cartridges while under the control of ISV applications that recognize the M8 barcode
label.
A tape cartridge is initialized when it is first loaded into a compatible tape drive
and data is written by the ISV application at the beginning of tape (sometimes
referred to as "labeling a tape" or "writing from BOT"). The tape drive establishes
the density of the media at that time.
If an un-initialized M8 cartridge is not initialized in a tape library that supports
un-initialized M8 cartridges, then the cartridge may inadvertently and silently be
initialized at the L7 density (i.e., at a 6 TB native capacity) even if the barcode label
states M8. This could occur with the usage of non-TS4500 tape libraries, stand-alone
LTO 7 tape drives, stand-alone LTO 8 tape drives, down-level LTO 8 tape drive
firmware, down-level TS4500 tape library firmware, or down-level ISV software
that does not recognize that M8 cartridges should only be mounted in LTO 8 tape
drives. M8 cartridges that are inadvertently initialized at the L7 density can
continue to be read and written in LTO 7 and LTO 8 tape drives; however, they
will remain limited to the 6 TB native capacity.
TS4500 tape library firmware version 1.4.1.2 added support for un-initialized M8
cartridges in addition to support for pre-initialized M8 cartridges. The TS3500 tape
library only supports pre-initialized M8 cartridges. In any tape product with M8
cartridges, the minimum LTO 8 tape drive firmware version is HB82.
116
IBM TS4500: Introduction and Planning Guide
Table 44. LTO 7 and LTO 8 cartridge types
Cartridge/
density type
Barcode label
L8
xxxxxxL8
M8
xxxxxxM8
L7
xxxxxxL7
Cartridge
packaging/
silkscreen
labeling
Native capacity
LTO Ultrium 8
12 TB
LTO Ultrium 7
9 TB
LTO Ultrium 7
6 TB
Tape drive
compatibility
LTO 8
LTO 8
LTO 7, LTO 8