Compaq 3000 manual Device I/O Module

RAID Array 3000 Controller Shelf

The controller supports one (for a single controller) or two (for dual-controllers) standard 72-pin cache SIMMs of up to 64 MB. In a dual-controller setup, both controllers must have identical cache configurations and the total usable cache (per controller) will be half the amount installed due to mirroring. Thus, in a sin- gle controller setup the maximum usable cache is 128 MB while a redundant setup has a maximum usable cache of 64 MB (per controller).

The RAID Array 3000 controller contains the following features:

∙Single PCB form factor for inclusion in the shelf

∙Support for dual hot-swap controller operation

∙Dual differential Ultra-Wide SCSI host channels

∙Dual single-ended Ultra-Wide SCSI disk channels

∙RAID level 0, 1, 0+1, 4, 5, and JBOD support

∙Voltage/temperature monitoring and support

∙Cluster support for specific operating systems

∙32 Logical Units (LUNs) per host channel (some operating systems may be limited to 8)

∙Support for spare disks

∙UPS backed write caching

∙Per LUN write cache/write back selection

∙Configuration/Maintenance via serial or host SCSI channel using (SWCC) StorageWorks Command Console (refer to the operating system platform kit for details).

∙Update of firmware via host channel

1.5.2 Device I/O Module

The device I/O module (Figure 1–5) provides the electrical interface between the RAID controller and the device buses. The module resides in the far right slot of the Shelf and has the following features:

∙Ability to electrically isolate the controller shelf and the device SCSI buses

∙Single channel, single shelf, single-ended bus operation

∙Single channel, single-ended bus operation for two Device Expansion Shelves using a Trilink adapter

∙External 16-bit data bus connections

∙Switch selectable 16-bit, 8-bit, or no SCSI bus termination

1–8 EK–SMCPQ–UG. C01