IBM 7145, Installation And User Manual

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Locator LED: Use this LED to visually locate the server among other servers. You
can use IBM Systems Director to light this LED remotely.
In a two-node configuration, this LED is lit on the primary server and flashes on the
secondary server during POST.
You can press this button or use an IPMI command to turn this LED on or off.
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 integrated
management module (IMM) is shut down; however, the server can respond to
requests from the IMM, 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.
In a two-node configuration, connect both servers to an ac power source as close
to the same time as possible to ensure optimum operation.
Turning on the server
Approximately 5 minutes, or up to 8 minutes in a 2-node configuration, after the
server is connected to ac power, the power-control button becomes active, and one
or more fans might start running to provide cooling while the server is connected to
power. You can turn on the server and all nodes in the partition and start the
operating system by pressing the power-control button.
If you are restarting a two-node server after it has been turned off, you must allow
extra time for the hardware to synchronize before you turn on the server again.
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
The systems-management software can turn on the server remotely.
v If your operating system supports the Wake on LAN feature, the Wake on LAN
feature can turn on the server.
Note: 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 IMM, such as a remote request to turn on the server.
While the server remains connected to ac power, one or more fans might continue
to run. To remove all power from the server, you must disconnect it from the power
source.
Important: To view the error LEDs on the system board, leave the server
connected to a 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 1. The System x3850 X5 and x3950 X5 server
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