Digital Equipment StorageWorks UltraSCSI DS-BA370 Series, User Manual

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Single-Ended I/O Modules
UltraSCSI RAID Enclosure 5–5
Error Reporting
The EMU monitors the status of the I/O modules for the following error
conditions:
•
The installation of incompatible I/O modules
•
A TERMPOWER problem
Incompatible I/O Modules
An I/O module error condition exists whenever any of the following
conditions exists:
•
Fewer than six operational I/O modules are installed
•
The I/O modules are not the same type
When the EMU detects an error conditions it automatically reports the
problem to the controller. An operational controller will automatically turn
off without implementing procedures to clear the cache module. The result
is that the controller will cease to operate and be in an error state; a state
that can adversely affect the integrity of the data.
Only when all I/O modules are the same type can an UltraSCSI RAID
subsystem function properly. The DIGITAL UltraSCSI controller only
supports single-ended buses. Therefore, you can only use single-ended I/O
modules (DS–BA35X MN). The enclosure does not support the following
conditions:
•
Installing a single-ended I/O module improperly
•
Installing fewer than six single-ended I/O modules.
•
Installing a termination I/O module
•
Installing a differential I/O module