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I manage 3 windows servers for my dad's business, and occasionally they lock up. I work remotely and would like to send commands to the motherboard to reboot using the buttons on the chasis. I have access to the network remotely.

All 3 servers are Supermicro servers, and two are the X7DB models with a serial port on the front. Can I send a reboot command using a device through the serial port? Would such a command work even with the OS is locked up and unresponsive?

I write some Python and do a little BASH and DOS scripting, so I probably have enough skill so compose some commands. But I don't know where to start reading about this topic.

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You should probably be looking to purchase some kind of smart power switch like mentioned in this question. – Zoredache Jan 27 '12 at 20:33
Yes, I wrote that question. But I desire to reboot gracefully instead of cycling power if possible. I found this product which advertises programmatic control of the power button and reset button on the chassis. I want to learn more on this subject. – steampowered Jan 27 '12 at 20:46
Doh, I didn't notice that. Honestly, I think you should just a go with one of those switches. Unless your system is really broken it doesn't seem like something you would use often enough to have to worry about it. And if something is broken that badly, and there is no option to reinstall/fix, I might be tempted to move the broken install into a VM instead, that way you can simply restart the VM. No hard-reboot required at all. – Zoredache Jan 27 '12 at 20:48
I have two concerns about recycling power. 1) Does it hurt the raid? There is a hardware raid running on a card installed. I am not concerned about data loss because I believe all of the data is written to the disk after the OS sits locked up for a few minutes with no interaction. 2) Will the power cycle leave the server in a shutdown state? Last time I pulled the plug on a computer, the computer did not turn back on when I plugged it back in. – steampowered Jan 27 '12 at 21:15
1) It shouldn't hurt the RAID, worst case, it may just decide it needs to do a verify and be slower for a while, the same thing would happen during an un-expected soft-reset. 2) in the BIOS/Setup options of your server there is almost certainly a configuration option to configure the behavior after a power loss. Usually all you have to do is configure it to power-up after AC outage. – Zoredache Jan 27 '12 at 21:20
up vote 0 down vote accepted

Obviously, if the OS is frozen you can't rely on anything but a hardwired mecanism into the motherboard.

Some uninterruptible power supply can be remotely controlled.
You can also use a watchdog PCI card.
You can find tons of devices like these:

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It seems you are saying there is no way to command a reboot if the OS is locked up. I found some products which advertise "out of band" rebooting, and this one specifically mentions control through buttons on the chasis. Maybe I am misunderstanding. – steampowered Jan 27 '12 at 20:44
IPMI is out of band, to the server hardware and OS. That's what it's for. Look at DRAC, iLo, etc. – mfinni Jan 27 '12 at 21:21

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