NonStop S-Series Planning and Configuration Guide (G06.29+)

System Components
HP NonStop S-Series Planning and Configuration Guide—523303-021
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Disk Drive Enclosure Components
Each Fibre Channel disk drive accesses both the X and Y fabrics by way of the
FCSAs.
In a NonStop S-series server, all disks can be in disk drive enclosures except the
system disk and its backup disk. These two disks must be internal SCSI disk drives
located in system enclosures.
Disk Drive Enclosure, Front View
These components are located in the rear of a disk drive enclosure:
•
Two blowers draw cooling air through the disk drive enclosure from front to rear.
•
One Environmental Monitoring Unit (EMU) is located at the left of the enclosure.
The EMU monitors the enclosure and detects conditions such as failed power
supplies, blowers, elevated temperatures, and external air sense faults.
•
Two Fibre Channel arbitrated loop I/O modules (FC-AL I/O A and FC-AL I/O B),
located on either side of the blowers, route data to and from the disk drives using
Loop A and Loop B. The FC-AL I/O modules pass Fibre Channel signals from
FCSAs in the IOAME to the disks in the disk drive enclosure and to any disk drive
enclosures daisy-chained to the first disk drive enclosure.
•
Two power supplies, located behind the blowers, power the disk drive enclosure
components.
•
Connections between IOAM enclosures and disk drive enclosures are made by
MMF cables.
•
Two AC power cords bring power from the PDU to the power supplies in the disk
drive enclosure.
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