HP MSA 30 User Manual page 13

System and Components
Figure 1-2: System, rear view
Item Description
1 Environmental Monitoring Unit (EMU)
2 Power supply units
3 I/O module (single-port or dual-port)
4 Blowers
Each system has either one or two internal SCSI buses, depending on the I/O module
installed. Each bus supports the Ultra320, Ultra3, and Ultra2 protocols.
IMPORTANT: The system does not support single-ended (SE) drives. Installing an SE drive
creates an error condition.
The system fault bus is supported by the HP StorageWorks HS series of array
controllers. Thus the controller, in conjunction with the EMU, can monitor the status
of the system components (primarily the power supply units and blowers) and report
any error conditions by causing the component and system LEDs to be illuminated
appropriately. Additionally, the controller can detect when a disk drive has been
removed or installed.
1-2 HP StorageWorks Modular Smart Array 30 User Guide