34 Planning: RAID Controller Modules
Host Channel LED Link/Rate Indications
Below eac h FC por t is a pa ir of LE D indicators. The status of any FC port can
be determined by applying Table3-1 to the condition of each LED pair.
RAID Controller Module—Additional Features

Battery Backup Unit

Each RAID controller 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, see "RAID Controller Module Backup Battery Unit"
on page 235.
NOTE: For virtual disks, the RAID 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.
20 FCIN port 0
LED 1 / LED 0
Displays link rate and port status per the accompanying
host channel LED link/rate table.
21 SAS OUT port
link/fault LED
Lights green when all four links are connected.
Lights amber when one to three links are disconnected.
Off when all links in the port are disconnected or cable is
disconnected.
Table 3-1. LED Status Indicators
LED 1 LED 0 CommRate
Off Off Link down
Off On 2 Gbps
On Off 4 Gbps
On On 8 Gbps
Item Component Function
book.book Page 34 Wednesday, June 8, 2011 5:01 PM