IBM System Storage DS3300, Installation, User'S, And Maintenance Manual

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v
Yes: Do not continue with this procedure. Contact your IBM technical-support
representative for assistance. Depending on the current service agreements,
you might have to return the equipment to the factory or local service center
for repair.
v
No: Go to step 2.
Attention: To avoid potential data loss, make sure that the storage
subsystem and storage expansion enclosure power switches are turned off
before you reset circuit breakers in the rack cabinet. Resetting circuit
breakers after an emergency situation while the storage subsystem and
storage expansion enclosure power switches are turned on can cause data
loss, because the configuration components might not be powered-on in the
correct sequence. See “Turning on the storage subsystem” on page 44 for
details about the correct power-on sequence.
2. After you check the storage subsystem for damage, make sure that the power
switches are off; then connect the DS3300 power cables, if required.
3. Check the system documentation of the hardware devices that you want to turn
on and determine the correct startup sequence.
Be sure to turn on all of the storage expansion enclosures and make sure that
no ESM or power-supply fault LEDs are lit before you turn on the DS3300.
In addition, consider the following items:
v The storage subsystem supports simultaneous power-on of the system
components; however, always follow the power-on sequence that is described
in the “Turning on the storage enclosure" section of the applicable
Installation, User’s, and Maintenance Guide during any attended power-on
procedure.
v
A storage subsystem in an optimal state recovers automatically from an
unexpected shutdown and unattended simultaneous restoration of power to
system components. After power is restored, contact your IBM
technical-support representative if any of the following conditions occur:
– The storage subsystem logical drives and subsystems are not displayed in
the Storage Manager graphical user interface.
– The storage subsystem logical drives and subsystems do not come online.
– The storage subsystem logical drives and subsystems seem to be
degraded.
4. Turn on the power to each device, according to the startup sequence.
5. Turn on both of the power-supply switches on the DS3300. The green LEDs on
the front and the rear of the DS3300 should remain lit. If other amber LEDs are
lit, see Chapter 6, “Solving problems,” on page 95.
Recovering from an overheated power supply
Each storage subsystem contains two power supplies. Each power supply contains
a built-in temperature sensor to prevent the power supply from overheating. Under
normal operating conditions, with an ambient air temperature range of 10°C to 35°C
(50°F to 95°F), the fans in the power-supply units maintain a suitable operating
temperature inside the module.
If the internal temperature reaches 65°C (149°F), the power supply shuts down
automatically. If both power supplies shut down because of overheating, the storage
subsystem has no power, and all LEDs are off.
The following factors can cause the power supplies to overheat:
Chapter 4. Operating the storage subsystem
57