Specifications

Escala Tower PL & S, E, T System Hardware
Chapter 3: External Storage and SAN Subsystems 37/116
9es3s1c3.doc
Rev 5.9
02/12/2003
3.5. The DAS 2000 Series Cabinet
DAS2900 discontinued as of 31 December 2000
The DAS 2000 deskside cabinet includes space for 5 to 20 replace-under-power (hot plug) disk drives,
two SPs, one mid-plane, three DC power supplies, and one cooling assembly to support the array's
operation and replace-under-power features. DAS2900 cabinets manage room for a Battery Backup
Unit for write cache security.
Hot plug technology results in dynamic expansion ability. Users can expand capacity or add any other
component while the system remains on line and operating.
There is no difference between the cabinet models.
3.6. The DAS 1000 Series Cabinet
DAS1300 discontinued as of 31 December 2000
In the DAS 1000 Series cabinet 3 to 10 hot-plug disk modules and two Power Modules can be housed.
All other features of the 2000 Series cabinet are supported.
3.7. The Power Subsystem
It includes power supplies (VSCs) (three for the DAS 2000 and 3000 Series or up to two for the DAS
1000 Series), AC input and AC circuit breaker. The subsystem supports n+1 DC power supply
configuration to allow for automatic failover in the event of a single supply failure. Each DC power
supply is contained in a replace-under-power module and can be replaced without disrupting
subsystem operation. Power fault design ensures data integrity even in the event of power loss during a
write operation.
The third Power Module is automatically configured with every DAS 2000 and 3000 Series.
3.8. The Cooling Subsystem
Like the power subsystem, the DAS 1000, 2000 and 3000 Series incorporate an n+1 cooling design.
Two fan pack modules are contained in a single cooling subsystem (one for the DAS 1000 Series), and
each fan pack module consists of 3 fans and a fan monitoring PCB. One fan in the system can fail
without impacting operation of the disk array. The entire cooling subsystem can be detached from the
array cabinet and replaced while the system continues to operate.