Understanding The Msc Leds And Switches - Silicon Graphics 2400 Owner's Manual

Chapter 7: Using the System Controller

Understanding the MSC LEDs and Switches

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The System Controller has one keyswitch, two push buttons, and four LED indicators.
The following paragraphs provide information on the use or significance of each control
or indicator.
The
Front Panel Keyswitch
The push button initiates a system-wide reset of the deskside. The
System Reset
keyswitch must be in the diagnostic position to use this button.
The
Non-Maskable Interrupt
system. The keyswitch must be in the diagnostic position to use this button.
The green LED lights when the system is plugged into an outlet and the AC
AC Power OK
circuit breaker is turned on. The Controller is receiving DC voltage (V_5 Aux) through
the midplane, as are other boards that require it.
The green LED lights three and one-half seconds after the keyswitch is
DC Power OK
turned to the On position. This indicates the system power supply is enabled and
operating properly.
The amber warning LED lights when the fans are running at high speed,
Fan Speed High
which may be an indication that ambient temperature is higher than optimal or a
non-critical fan has failed. When a non-critical fan fails, the remaining fans are set at full
speed to compensate. In this case, a service call should be placed immediately.
The
Over Temperature Fault
air temperature or fan failure detection causes a shutdown of the system. If the
environmental temperature exceeds the system's tolerance, or if a critical fan fails, the
controller shuts down the system. In some cases, a service call should be placed
immediately. See the section "MSC Shutdown" in Chapter 8 for tips on how to
troubleshoot this problem area.
selects Standby, On, or Diagnostic status for the system.
(NMI) switch issues a reset signal to all Node boards in the
amber warning LED lights when the controller's incoming