IBM TotalStorage DS4400, User Manual

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Fault-B
Amber light indicates
controller fault.
Normal status: Off
Problem status: On
Power
Green light indicates that
power is on.
Normal status: On
Problem status: Off
Heartbeat
Green light indicates that the
controller is working.
Normal status: On (blinking)
Problem status: On
Status
(8 lights including the Heartbeat)
Green lights indicate controller
status.
Controller status
indicator lights
Reset switch
Controller A
Controller B
Servicing notes
Consider the following when servicing the controllers in the DS4400 Storage Server:
v
The DS4400 Storage Server supports two controller CRUs, which attach to hosts
through Fibre Channel connections.
v You can hot swap or replace a failed controller while the DS4400 Storage Server
is in operation as long as the host has a Fibre Channel connection to the
functioning controller and is in a “passive” or “offline” status in the
storage-management software.
v If cache mirroring is enabled in redundant controllers and one controller fails, the
second controller assumes processing functions without data loss. However,
some or all data might be lost if cache mirroring is disabled and a failure occurs
before data is written from cache memory to disk.
v If you replace the controller CRU and still experience problems, the DS4400
Storage Server might have other defective components or connections. Check
the storage-management software for indications of other component failures.
v When a controller CRU fails, the fault light on the affected controller is lit. For
more information about indicator lights, see “RAID controller indicator lights” on
page 29.
v The two controllers are automatically synchronized when you replace a failed
controller. The storage-management software automatically synchronizes the
firmware between the existing controller and the new controller.
Figure 33. Controller status indicator lights
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IBM TotalStorage DS4400 Fibre Channel Storage Server: User’s Guide