Turning Off Power to All Devices

You need to turn off power to all system devices when you do the following:

• Replace or add hardware.

• Move the system from one location to another.

• Prepare for an expected power outage or natural disaster such as an approaching electrical storm.

Turn off the power to system devices, including the CPU, the monitor, and external devices such as disks, tapes, and printers.

Before you turn off the power to all system devices, shut down the system cleanly, as described in the preceding sections.

How to Turn Off Power to All Devices

1. Select one of the following methods to shut down the system:
   • If you are shutting down a server, see How to Shut Down a Server.
   • If you are shutting down a stand-alone system, see How to Shut Down a Stand-Alone System.
2. Turn off the power to all devices after the system is shutdown. If necessary, also unplug the power cables.
3. After power can be restored, use the following steps to turn on the system and devices.
   1. Plug in the power cables.
   2. Turn on the monitor.
   3. Turn on disk drives, tape drives, and printers.
   4. Turn on the CPU.

      The system is brought to run level 3.