1-2
Compaq StorageWorks SSL2000 Series LIbrary Maintenance and Service Guide
The drives used in the Library read from and write to 8 mm AIT 2 data tape cartridges with a
native capacity of 35 GB or 50 GB (see Table 1-1).
Table 1-1
Library Models
Model Number
Configuration
175195-B21
175195-B22
1 Drive, AIT 2 50 GB, tabletop, LVD/SE
2 Drive, AIT 2 50 GB, tabletop, LVD/SE
175196-B21
175196-B22
1 Drive, AIT 2 50 GB, rackmount, LVD/SE
2 Drive, AIT 2 50 GB, rackmount, LVD/SE
Multi-Unit Library Systems
The Library features SmartScale Storage™ , an architecture that lets you combine multiple units
into an integrated library system. This architecture enables the robotics in each of the Library
units to exchange cartridges by means of a vertical PTM. Under the control of the unit you
configure to be the master unit, the PTM integrates the robotics in the individual slave units into
a single high-performance library robotics system. For more information, see Appendix C,
“Installation.”
The SmartScale Storage architecture gives you a truly scaleable library that can smoothly
expand to meet your growing storage needs. You can start with a system configured to your
present requirements, confident that as your storage needs evolve, adding units and extending
the PTM can easily modify the Library. Add drives for faster performance or magazine space
for greater capacity, as needed. Then just turn on the power, and immediately the system
updates the system map so the host is informed of the expanded capability. The SmartScale
Storage architecture has built-in redundancy so that if the master unit fails, a slave unit (slave 0)
can be configured to take over as the master unit. This is done without having to make hardware
changes except moving the motor cable to the new master.
Tape Cartridge Magazine Mail Slot
If your host software permits, you can use the front slot in the tape cartridge magazine (the first
slot you see when you open the door) as a mail slot for inserting or removing a single cartridge
without interrupting host operations in progress. The mail slot is implemented as the SCSI
IMPORT/EXPORT commands.
SCSI Interface
The unit presents the following to the host:
■
A single SCSI medium changer device with a single SCSI medium transport element
■
A number of SCSI storage elements equal to the total number of cartridge magazine slots
■
A single SCSI import/export element
■
A number of SCSI data transfer elements equal to the total number of drives in the Library
