Raid Controller Module-Additional Features; Battery Backup Unit; Storage Array Thermal Shutdown - Dell PowerVault MD3860f Owner's Manual

Item Indicator, Button, or
Connector
5 SAS OUT port
6 Diagnostic LED
7 Controller power
indicator
8 Service action required
indicator (system)
9 Service action allowed
indicator
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.
Icon Description
Provides SAS connection for cabling to a downchain
expansion enclosure.
The numeric display consists of two seven-segment LEDs
that provide information about enclosure identification
and diagnostics.
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
Off
Indicates that you can safely
remove the expansion module
from the system.
Indicates that you cannot remove
the expansion module from the
system.
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