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v The green Cache active LEDs on the back of the storage server are off.
b. If applicable, use the operating system software to disconnect the storage
server logical drives from the host before the storage server is powered off.
Attention: To turn off all power to the storage server, you must turn off both
power-supply switches and disconnect both power cords. Use the procedure in
step 4 for the proper shutdown sequence.
4. Turn off the power to each device based on the following shutdown sequence:
a. Turn off power to the host before the storage server. If the host must stay
powered on to support an existing network, see the operating system
documentation for information about disconnecting the storage server logical
drives from the host before the storage server is powered off.
b. Turn off power to the storage server before you turn off power to the
expansion units. Turn off both power supply switches on the back of the
storage server.
c. 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 server.
5. After you perform the necessary maintenance procedures, turn on the power
using the procedure in “Turning on the storage server” on page 35.
Restoring power after an unexpected shutdown
The storage server might shut down unexpectedly under any of the following
conditions:
Attention: There might be data loss in each of the following cases:
v The internal temperature of the storage server exceeds the maximum operating
temperature (an over-temperature condition).
If both fan CRUs fail or are unable to maintain an internal temperature below
70°C (158°F), one or both of the power supplies in the storage server will shut
down. If both power supplies shut down, the unit is inoperable.
The storage-management software warns you if the temperature of the unit is
rising, before it has risen sufficiently to shut down the power supplies. The first
warning comes when the storage server internal temperature exceeds 45°C
(113°F). The storage server shuts down if the temperature rises to 70°C (158°F).
v There is a general power failure or a loss of power to the unit.
v You are forced to shut down the storage server without performing the normal
shutdown procedures (listed in “Turning off the storage server” on page 36)
because of an emergency situation.
Attention: To avoid damage to the hardware, take special care when restarting
the system after an unexpected shutdown.
If the storage server shuts down unexpectedly, go to “Restoring power after an
over-temperature shutdown” on page 38. Otherwise, go to “Restoring power after an
emergency shutdown” on page 38.
Chapter 4. Operating the storage server 37