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If you're up for DIY, it's easy to turn a sufficiently long serial break into a toggle on a reset line and/or power button with a couple of discrete components.

A serial break is the only situation in which an RS232 line is driven +ve with greater than 90% duty cycle: charge a cap slowly on +ve, discharge quickly on -ve (diode), drive a mosfet gate to pull reset line low only when it's been +ve for quarter of a second or so.

Easily the hardest part of doing this is finding a 'clean' way to get a wire attached to the serial RX and GND pins from the inside the case rather than bodging something really ugly. Some boards have a front-facing serial port, though, which has a pin header and cable => easy to tap into.

I'd soldered onto the little legs on a stand off board DB9 port on one batch of machines I installed, and then ended up being thwarted on the next batch of boards which had a slightly different (more enclosed) style of DB9 port that made it much harder to get at the pins.

Whatever you do along these lines will be infinitely better than the insecure, overengineered catastrophe of vendor IPMI/BMC firmware. I wish someone less lazy than me would make a product along these lines... ;-)



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