LED Indicators and Switches
Non-Maskable Interrupt Switch
Crash dump analysis is an essential part of eliminating reliability problems such as hangs or
crashes in operating systems, device drivers, and applications. Many crashes freeze a system,
requiring you to do a hard reset. Resetting the system erases any information that supports
root cause analysis.
Systems running the Microsoft Windows NT operating system experience a blue screen trap
when the operating system crashes. When this happens, Microsoft recommends that system
administrators perform a non-maskable interrupt (NMI) event by pressing a dump switch.
The NMI event allows a hung system to once again become responsive.
The NMI switch, or SW4, is used only in the event of a service emergency that requires a
complete data dump in preparation for recovering the system from a blue screen or other
catastrophic event.
NOTE: Pressing the NMI switch during normal operation will crash the server.
HP ProLiant ML370 Generation 3 Server Maintenance and Service Guide 4-15