- IBM switch Users and Maintenance Guide

Attention: To avoid damage to the hardware, take special care when you restart
the system after an unexpected shutdown.
If the storage server shuts down unexpectedly, go to “Restoring power after an
over-temperature shutdown.” Otherwise, go to “Restoring power after an emergency
shutdown.”
Note: Unattended restoration of power is supported; however, if power restoration
is attended, you should follow the best practices guidelines and the power
restoration sequence in “Turning on the storage server” on page 66.
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 will help safeguard your equipment from potential damage due to electrical
surges when power is restored. If the storage server loses power unexpectedly, it
might be due to a hardware failure in the power system or midplane (see Chapter 6,
“Hardware maintenance,” on page 111).
Use this procedure to shut down the storage server during an emergency:
1. If you have time, stop all I/O activity to the storage server by shutting down the
host or disconnecting the storage server logical drives through the host.
2. Check the LEDs (front and back). Make note of any Fault LEDs that are on so
you can correct the problem when you turn on the power again.
3. Turn off all power-supply switches; then unplug the power cords from the
storage server.
Restoring power after an emergency shutdown
Use this procedure to restart the storage server if you turned off the power-supply
switches during an emergency shutdown, or if a power failure or a power outage
occurred:
1. After the emergency situation is over or power is restored, check the storage
server for damage. If there is no visible damage, continue with step 2;
otherwise, have your system serviced.
2. After you have checked for damage, ensure that the power-supply switches are
off; then plug in the storage-server power cords.
3. Complete step 2 on page 66 to determine the proper power-on sequence for
your system.
4. Complete steps 3 and 4 on page 66 to turn on power to the devices in your
system and to check the status of the storage server.
Restoring power after an over-temperature shutdown
Use this procedure to restart the storage server after an unexpected shutdown due
to an over-temperature condition:
1. Make sure that the power-supply switches on the back of the storage server are
turned off.
2. Do whatever is necessary to cool the unit (replace the fans, use external fans to
cool the room, and so on).
3. Check all components and cables for visible damage. Do not start the storage
server if you find evidence of damage.
Chapter 4. Operating the storage server 69