IBM TotalStorage DS4000 Hardware Maintenance Manual page 140

2. Check the system documentation for all the hardware devices you intend to
3. Turn on the power to each device, based on the startup sequence.
4. Turn on both power supply switches on the back of the unit.
Turning off the expansion unit
Attention: Except in an emergency, never turn off the power if any Fault LEDs
are lit on the expansion unit. Correct the fault before you turn off the power, using
the proper troubleshooting or servicing procedure. This action ensures that the
expansion unit will power up correctly later. For guidance, see "Symptom-to-FRU
index" on page 115.
The expansion unit is designed to run continuously, 24 hours a day. After you turn
on the expansion unit, do not turn it off. Turn off the power only when:
v Instructions in a hardware or software procedure require you to turn off the
v A service technician tells you to turn off the power.
v A power outage or emergency situation occurs (see "Performing an emergency
CAUTION:
The power control button on the device and the power switch on the power
supply do not turn off the electrical current supplied to the device. The device
also might have more than one power cord. To remove all electrical current from
the device, ensure that all power cords are disconnected from the power source.
Perform the following steps to turn off the power:
1. Check the system documentation for all hardware devices you intend to turn
2. Make sure that all I/O activity has stopped.
3. Make sure that all amber Fault LEDs are off. If any Fault LEDs are lit (drives,
4. Turn off both power supply switches on the back on the expansion unit.
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c. The tray number switches on the expansion unit are set correctly. (See the
IBM Product Installation Guide for more information.)
turn on and determine the proper startup sequence.
Note: Be sure to turn on the IBM FAStT EXP500 before you turn on the server.
Attention: If you are restarting the system after a normal shutdown, wait at
least 10 seconds before you turn on the power supply switches.
The expansion unit might take a few seconds to power up. During this time,
you might see the amber and green LEDs on the expansion unit turn on and
off intermittently. When the startup sequence is complete, only the green LEDs
on the front and back and the amber Bypass LEDs for unconnected GBIC ports
should remain on. If other amber LEDs remain lit, see "Symptom-to-FRU
index" on page 115.
power.
shutdown" on page 113).
off and determine the proper power-down sequence.
power supplies, or fans), correct the problem before you turn off the power. For
guidance, see "Symptom-to-FRU index" on page 115.