IBM System Storage DS5020, Installation, User'S, And Maintenance Manual

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The Service Action Allowed status LED automatically turns on or off as conditions
change. Wait at least two minutes after you replace each component for the
controller to recognize the new component and update the LED status. In most
cases when a single component fails, the Service Action Allowed status LED turns
on steadily when the Needs Attention status LED is turned on for the component.
Replacing a controller
Attention: Before you replace a controller, verify the following:
v
The replacement controller part number matches the part number of the
controller to be replaced. To provide full functionality, the two controllers must
have the same cache memory capacity, same number of host ports, same types
of host ports (FC or iSCSI), and same FRU part number. Inserting a
non-compatible controller causes the controller to be placed in a lockout state by
the other controller in the DS5020 chassis.
Note: The DS5020 storage subsystem controller FRU is not compatible with the
DS4200 Express or DS4700 storage subsystem controller FRU. See the
“Parts listing” on page 166 for more information about compatible
controllers.
v
Both power supply and fan units must be connected and powered on with no
Needs Attention LEDs lit. Make sure that the Power LEDs on each of the power
supply and fan units are lit. If either of the power supply and fan units is not
optimal, replace that component before you proceed with the controller
replacement procedure.
v If you are replacing an optimal controller, first make sure that the other controller
is optimal and that the Fibre Channel path from the hosts to the other controller
is also optimal.
Each controller has a unique hardware Ethernet address, which is printed on a label
on the front.
Before you begin, ensure that you wear an anti-static wrist strap.
Use the following procedure to replace a controller in an DS5020 storage
subsystem:
1. Use the DS Storage Manager client software to print a storage subsystem
profile. Move logical drive ownership to the other controller. If the controller you
are replacing has failed but is still operating, move the failed controller to an
Offline state.
Attention: Never remove a controller unless the Service Action Allowed
status LED is turned on. Doing so can result in a potential loss of data.
2. Locate the failed controller by checking the Needs Attention status LEDs on
the controllers in the storage subsystem.
3. Is the Service Action Allowed status LED turned on?
v
Yes – Go to step 4 on page 125.
v No – Another component might require attention before you can remove the
controller. Use the Recovery Guru function in the DS5020 Subsystem
Management window to identify and correct any additional failures. If there
are none, proceed with step 4 on page 125 to replace the controller.
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IBM System Storage DS5020 Storage Subsystem: Installation, User’s, and Maintenance Guide