IBM 84875MU, User 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 is shut down; however, the server
can respond to remote requests to turn on the server. The power-on LED flashes to
indicate that the server is connected to an ac power source but is not turned on
(standby mode).
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 (ASM)
interconnect network that contains at least one server with an optional Remote
Supervisor Adapter II installed, the server can be turned on from the Remote
Supervisor Adapter II user interface.
v
If the operating system supports the systems-management software for an
optional Remote Supervisor Adapter II, the systems-management software can
turn on the server.
v If the operating system supports the Wake on LAN
®
feature, the Wake on LAN
feature can turn on the server.
v
If an optional Remote Supervisor Adapter II is installed in the server, the server
can be turned on from the Remote Supervisor Adapter II user interface.
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 remote requests 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 the operating-system documentation for information about shutting down the
operating system.
Chapter 1. Introduction
7