Dell E08J Series RAID Controller Module-Additional Features, Storage Array Thermal Shutdown

Item	Indicator, Button, or	Icon	Description
	Connector
5	SAS OUT port		Provides SAS connection for cabling to a downchain
			expansion enclosure.
6	Diagnostic LED		The numeric display consists of two seven-segment LEDs
			that provide information about enclosure identification
			and diagnostics.

7Controller power indicator

8Service action required indicator (system)

9Service action allowed indicator

The controller power indicator lights green when controller power is on.

The service action required indicator lights amber when there is a fault in one of the components in the system.

CAUTION: Remove the expansion module from the system only if the service action allowed indicator lights blue. Removing the expansion module from the system when the service action allowed indicator is off may damage the system.

Blue	Indicates that you can safely
	remove the expansion module
	from the system.

Off	Indicates that you cannot remove
	the expansion module from the
	system.

RAID Controller Module—Additional Features

Battery Backup Unit

Each RAID controller module contains a two-cell Lithium ion nanopolymer battery backup unit (BBU). It provides power to the RAID controller module in the event of a power outage.

NOTE: For virtual disks, the controller firmware changes the data cache setting based on the state of the battery. If the battery is missing or does not have sufficient charge, the controller flushes the cache and sets the Write-Cache attribute to Write-Through for all virtual disks. When the battery is replaced, Write-Back is re-enabled.

Storage Array Thermal Shutdown

The system automatically shuts down when system temperature exceeds the safe threshold. The battery backup unit protects against data loss by providing power to offload cache to non-volatile memory in the event of power loss.

Temperature threshold values determine the temperature at which shutdown occurs. These thresholds cannot be changed.

NOTE: It is not necessary to shut down any expansion enclosures attached to the storage array when thermal shutdown occurs.

19