IBM DS4800 User, Installation And Maintenance Manual page 123

Power-off overview
Review the following information before you continue with the power-off
procedure below.
Turn off the power to each device based on the following shutdown sequence:
1. Turn off power to the host before the storage subsystem. If the host must
stay powered on to support an existing network, see the operating system
documentation for information about disconnecting the storage subsystem
logical drives from the host before the storage subsystem is powered off.
2. Turn off power to the storage subsystem before you turn off power to the
storage expansion enclosures. Turn off both power supply switches on the
back of the storage subsystem.
3. Turn off power to other supporting devices (for example, management
stations, fibre-channel switches, or Ethernet switches).
Note: You do not need to perform this step if you are servicing only the
storage subsystem.
Use the following procedure to turn off power to one or more storage subsystems
for a planned shutdown. To turn off power for an unplanned shutdown, see
"Performing an emergency shutdown" on page 103.
Before proceeding, use the DS4000 Storage Manager client to determine the status
of the system components and special instructions. The operating system software
might require you to perform other procedures before you turn off the power.
1. Stop all I/O activity to the storage subsystems.
2. Determine the status of all storage subsystems and components in the
configuration by completing the following steps.
a. Check all LEDs on each component in the storage expansion enclosures.
Ensure that all the LEDs show normal status.
b. Check all LEDs on each component in the storage subsystem. Ensure that
all the LEDs show normal status. For information about LED status, see
"Checking the LEDs" on page 111.
c. Open the Subsystem Management Window for the configuration and display
the Physical View for the configuration.
d. Review the status of the configuration components shown in the Subsystem
Management Window by selecting the appropriate component button for
each storage subsystem.
The status for each component will be either Optimal or Needs Attention.
3. Are the LEDs indicating normal operation, and is the status Optimal on all the
configuration components?
v Yes – Go to step 5 on page 102.
v No – Go to step 4.
4. To diagnose and correct the fault, complete the following steps.
a. Run the Recovery Guru by selecting the Recovery Guru toolbar button in
the Subsystem Management Window.
b. Complete the recovery procedure.
If the Recovery Guru directs you to replace a failed component, use the
individual LEDs on the storage subsystem to locate the failed component.
Chapter 4. Operating the storage subsystem
101