IBM Eserver 345 Series, Option Installation Manual

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Server power features
When the server is connected to an ac power source but is not turned on, the
operating system does not run, and all core logic except for the service processor is
shut down; however, the server can respond to requests from the service processor,
such as a remote request to turn on the server. The power-on LED flashes to
indicate that the server is connected to ac power but not turned on.
Turning on the server
Approximately 20 seconds after the server is connected to ac power, the
power-control button becomes active, and you can turn on the server and start the
operating system by pressing the power-control button. The server can also be
turned on in any of the following ways:
v If a power failure occurs while the server is turned on, the server will restart
automatically when power is restored.
v If the server is connected to an Advanced System Management interconnect
network that contains at least one server with an optional Remote Supervisor
Adapter installed, the server can be turned on from the Remote Supervisor
Adapter user interface.
v
If your operating system supports the system-management software for an
optional Remote Supervisor Adapter, the system-management software can turn
on the server.
v If your operating system supports the Wake on LAN
®
feature, the Wake on LAN
feature can turn on the server.
Note: When 4 GB or more of memory (physical or logical) is installed, some
memory is reserved for various system resources and is unavailable to the
operating system. The amount of memory that is reserved for system
resources depends on the operating system, the configuration of the server,
and the configured PCI options.
Turning off the server
When you turn off the server and leave it connected to ac power, the server can
respond to requests from the service processor, such as a remote request to turn
on the server. To remove all power from the server, you must disconnect it from the
power source.
Some operating systems require an orderly shutdown before you turn off the server.
See your operating-system documentation for information about shutting down the
operating system.
Chapter 2. Installing options
13