IBM DCS3700, Installation, User'S, And Maintenance Manual

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Attention: To avoid potential data loss, make sure that the storage system and the expansion
enclosure power switches are turned off before you reset circuit breakers in the rack. Resetting circuit
breakers after an emergency situation while the storage system and the 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 “Powering on the DCS3700” on page 68 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 DCS3700 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.
4. Turn on both of the power-supply switches on DCS3700 expansion enclosures and make sure that no
ESM or power-supply fault LEDs are lit before you power on the DCS3700 storage system.
In addition, consider the following items:
v
The storage subsystem supports simultaneous power-on of the system components; however,
always check the system documentation of the hardware devices that you want to turn on and
determine the correct startup sequence.
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 arrays are not displayed in the Storage Manager
graphical user interface.
– The storage subsystem logical drives and arrays do not come online.
– The storage subsystem logical drives and arrays seem to be degraded.
5. Turn on both of the power-supply switches on the DCS3700 storage system. See “Solving problems”
on page 129.
Recovering from an overheated power supply
Each storage enclosure 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 40°C (50°F to 104°F), the fans in the power supplies 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:
v
An unusually high room temperature
v
Fan failures in the power supplies
v
Defective circuitry in a power supply
v Blocked air vents
v
Failures in other devices in the configuration or rack
If a fan failure causes overheating, the system-error LED and overtemperature LEDs on the front bezel
are lit. The fault LED on the power supply might also be lit.“Checking the LEDs” on page 73 shows the
location of the LEDs on the DCS3700.
If the storage subsystem temperature exceeds 45°C (113°F), the storage management software displays a
Needs Attention icon in the Subsystem Management window. If the air temperature inside the rack
reaches 65°C (149°F), the power supplies automatically shut down. If event monitoring is enabled and
event notification is configured, the software issues two critical-problem notifications.
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IBM System Storage DCS3700: Installation, User, and Maintenance Guide