Restoring Power After An Unexpected Shutdown - IBM TotalStorage DS4100 Installation, User's, And Maintenance Manual

3. Stop all I/O activity to the storage server and attached expansion units. Make
4. Before the storage server is powered off, use the operating system software to
5. If applicable, use the operating system software to disconnect the storage
6. Turn off the power to each device based on the following shutdown sequence:
7. After you perform the necessary maintenance procedures, turn on the power

Restoring power after an unexpected shutdown

The storage server might shut down unexpectedly under any of the following
conditions:
Attention:
v The internal temperature of the storage server exceeds the maximum operating
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
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IBM TotalStorage DS4100 Storage Server: Installation, User's, and Maintenance Guide
sure that:
v All of the green Drive active LEDs on the front of the storage server (and on
all attached expansion units) are not flashing.
v The green Cache active LEDs on the back of the storage server are 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 6 for the proper shutdown sequence.
either disconnect the storage server logical drives from the host or to flush the
logical drive data cache in the host server memory.
server logical drives from the host before the storage server is powered off.
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.
using the procedure in "Turning on the storage server" on page 66.
There might be data loss in each of the following cases:
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 DS4000 Storage Manager client 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).
shutdown procedures (listed in "Turning off the storage server" on page 67)
because of an emergency situation.