Performing An Emergency Shutdown; Restoring Power After An Unexpected Shutdown - IBM DS3500 Installation, User's, And Maintenance Manual

Performing an emergency shutdown

Attention: Emergency situations might include fire, flood, extreme weather conditions, or other
hazardous circumstances. If a power outage or emergency situation occurs, always turn off all power
switches on all computing equipment. This helps to safeguard your equipment from potential damage
due to electrical surges when power is restored. If the storage subsystem loses power unexpectedly, it
might be due to a hardware failure in the power system or in the midplane.
To shut down the system during an emergency, complete the following steps:
1. If you have time, stop all I/O activity to the storage subsystem by shutting down the host or
disconnecting the storage subsystem logical drives through the host.
2. Check the LEDs. Make note of any amber LEDs that are lit so that you can correct the problem when
you turn on the power again.
3. Turn off all power-supply switches, starting with the storage subsystem first and followed by the
storage enclosures. Then, disconnect the power cables from the storage subsystem.
4. If there are enclosures with dc power supplies in your storage subsystem, turn off the -48V disconnect
devices after turning off the power-supply switches.

Restoring power after an unexpected shutdown

To restore power to the storage subsystem in a configuration after an unplanned shutdown, complete the
following steps.
DANGER
Never turn on any equipment when there is evidence of fire, water, or structural damage.
1. After the emergency situation is over or power is restored, visually check the storage subsystem for
damage. Is there evidence of damage to any of the storage subsystem components, cables, or
equipment that is attached to the storage subsystem?
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
enclosure power switches are turned off before you reset circuit breakers in the rack. Resetting
circuit breakers after an emergency situation while the storage subsystem and storage 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 4-2 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 DS3500 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 enclosures and make sure that no ESM or power-supply fault
LEDs are lit before you turn on the storage subsystem.
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.
Chapter 4. Operating the storage subsystem and storage enclosure
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