Server Status with Keyboard LEDs
This page describes how you can use keyboard LEDs to monitor the status of a linux server.Martin writes:Instead, I use some software running on each linux box, to toggle the keyboard LEDs on and off to indicate status information. Instead of having a full-size keyboard plugged into each server, I disassemble the keyboard, and remove all the unnecessary components, leaving just the circuitry required for controlling the LEDs. The standard LEDs are replaced with new LEDs that are easier to mount, and an additional power LED is added, allowing the three LEDs (NumLock, CapsLock, ScrollLock) to be used to indicate various status information.
   Server Status with Keyboard LEDs
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