ElectroRF
The idea is not necessarily to turn the PC off, but to use the ON/OFF nature of the strip and the control of the strip ti be the interface.
e.g. You make something that when power is applied, the servo does it's thing.
So, check out Moxa or Lantronix:
https://www.moxa.com/product/NE-4100T.htm These have a few TTL I/O ports.
So, let's say you have a program on the PC that resets a watchdog timer. The watchdog timer goes off an an email is sent to you. Alternatively, the linux box could use Ping. Then by connecting to the serial server, you could activate a TTL port.
The device you build, just has to look at a TTL
So ask yourself a few questions:
1. How much automation do I want?
e.g. email notification that server is down, automatic
2. How can I tell server is down?
a) Ping and is ping allowed?
b) Watchdog timer. Server talks to device every so often and when it fails, a reset happens.
Boot time + 50% could be the watchdow time.
c) The applications no worky
3) How many do I need? How cost effective using learning curve issues etc.
4) Can I use commercial hardware?
5) Yes, you did mention an RC servo, but you have to convert rotary to linear motion. Why not go linear from the start"
Options:
a) Linear: **broken link removed**
b) Floppy drive linear actuator fitted possibly with a spring.
6) Who is going to use it? How user friendly does it have to be? Is it more like person A discovers server down and makes a phone call to your IT department where 1 or 2 people are allowed to operate the device.
7) How secure does the activation have to be? That's where ssh comes in to play. You can set ssh up so that passwords are not required on machines that use it. Certificates are used instead. They may have to be Linux boxes or Windows boxes using Cygwin.
I once set Cygwin up for a man-in-the middle where an external access via VPN (allowed access to a machine that had access to a secure server), but I wanted to access the secure server via VPN directly. Specifically, I wanted to be able to transfer files from the secure server to my laptap logged in from home via VPN without transferring it to an intermediate machine first. It worked for while until they fixed it.
They are ideas and ideas that may not work, but 99% of the connectivity stuff may be done for you.
It's possible that the only glue might be a small PICAXE program that responds to a TTL port.