Cutting power by software - what device do i need?

[diep]

Is it possible to control an individual usb port? If so, then you could use a usb controlled power strip. It monitors the 5 volt usb output and shuts down when the voltage ceases.

If not, then you might have to do what Bob suggested. Get a usb relay, and use that to control the power to an intermediate receptacle outlet which you plug the switch into. I found one here that is not too expensive:
http://www.pencomdesign.com/1ch_usb_relay.htm

I'm not such a fan of USB. Actually the motherboards have a com port, RS232, so maybe i can use some old fashioned thing there.

Same principle applies then i suppose.

Usually in bios i turn off usb entirely - too easy to hack machines that have usb enabled.

Now i want to control of course the fans of the switch, the next thing to also monitor is the fans i intend to build to blow air in and out of the room, though i have some months for that to go when it gets a tad hotter and it has to lose the cluster heat to outside - that will be a lot easier to control though and probably no relays needed as just have to shutdown the machines then.

p.s. the relays you advice seems a windoze only relay - not gonna work at linux here

[bob]

Is it possible to control an individual usb port? If so, then you could use a usb controlled power strip. It monitors the 5 volt usb output and shuts down when the voltage ceases.

If not, then you might have to do what Bob suggested. Get a usb relay, and use that to control the power to an intermediate receptacle outlet which you plug the switch into. I found one here that is not too expensive:
http://www.pencomdesign.com/1ch_usb_relay.htm

I'm not such a fan of USB. Actually the motherboards have a com port, RS232, so maybe i can use some old fashioned thing there.

Same principle applies then i suppose.

Usually in bios i turn off usb entirely - too easy to hack machines that have usb enabled.

Now i want to control of course the fans of the switch, the next thing to also monitor is the fans i intend to build to blow air in and out of the room, though i have some months for that to go when it gets a tad hotter and it has to lose the cluster heat to outside - that will be a lot easier to control though and probably no relays needed as just have to shutdown the machines then.

p.s. the relays you advice seems a windoze only relay - not gonna work at linux here

I have seen RS232 to USB and such scattered around over the years, although it might be less common today...

[diep]

Is it possible to control an individual usb port? If so, then you could use a usb controlled power strip. It monitors the 5 volt usb output and shuts down when the voltage ceases.

If not, then you might have to do what Bob suggested. Get a usb relay, and use that to control the power to an intermediate receptacle outlet which you plug the switch into. I found one here that is not too expensive:
http://www.pencomdesign.com/1ch_usb_relay.htm

I'm not such a fan of USB. Actually the motherboards have a com port, RS232, so maybe i can use some old fashioned thing there.

Same principle applies then i suppose.

Usually in bios i turn off usb entirely - too easy to hack machines that have usb enabled.

Now i want to control of course the fans of the switch, the next thing to also monitor is the fans i intend to build to blow air in and out of the room, though i have some months for that to go when it gets a tad hotter and it has to lose the cluster heat to outside - that will be a lot easier to control though and probably no relays needed as just have to shutdown the machines then.

p.s. the relays you advice seems a windoze only relay - not gonna work at linux here

I have seen RS232 to USB and such scattered around over the years, although it might be less common today...

The problem of todays operating systems, linux AND windows, is that some cheap USB driver produced in China that's in an usb device, it can take over your entire computer, as all drivers can control the kernel, the kernels are all monolithic. Linux and windows are total outdated there. Furthermore they are total behind in SMP logics; every packet, even UDP/RAW, gets central locked in the linux kernel. Total outdated way of working; little advantage in multiprocessing there is in this manner; and postings from Linus indicate he only believes in single processor logics, load balancing it over the different cores he just is total not interested in.

That will stop progress of linux bigtime.

Windows of course securitywise and moneywise is an even bigger disaster for now, so difficult to do statements about.

All this is not very helpful for low latency communication and basically takes care that Mellanox is the absolute king in low latency performance for a decent price.

But we would get in another discussion now, it seems your relays solution is the way to go and pretty cheap. No need for programming an entire legorobot

[bhlangonijr]

The USB relay solution looks workable, although not real cheap...

The USB relay solution is an awkward solution. It very much reminds me old cartoons of Gyro Gearloose and his inventions. I think there are other more standardized and simpler ways of solving this problem. BTW, an equivalent solution but way cheaper is installing a mousetrap triggered by a pressurized recipient with boiling water, caused by the heat produced within the device. The mousetrap would be equipped with blades that will cut the power wires off, interrupting power supplying... lol

Putting the jokes aside I wonder if there is a standard interface like ACPI in this switch, so that you can configure the thresholds for turning off the power supply.


The other option would be remotely monitoring the switch temperature by using a protocol like SNMP (or whatever protocol the device supports) and whenever occurs an overheat it sends a shutdown command directly to the UPS (it depends on what is your device's external power supply). There are plenty of cheap UPS that supports remote management.

[diep]

The USB relay solution looks workable, although not real cheap...

The USB relay solution is an awkward solution. It very much reminds me old cartoons of Gyro Gearloose and his inventions. I think there are other more standardized and simpler ways of solving this problem. BTW, an equivalent solution but way cheaper is installing a mousetrap triggered by a pressurized recipient with boiling water, caused by the heat produced within the device. The mousetrap would be equipped with blades that will cut the power wires off, interrupting power supplying... lol

Putting the jokes aside I wonder if there is a standard interface like ACPI in this switch, so that you can configure the thresholds for turning off the power supply.


The other option would be remotely monitoring the switch temperature by using a protocol like SNMP (or whatever protocol the device supports) and whenever occurs an overheat it sends a shutdown command directly to the UPS (it depends on what is your device's external power supply). There are plenty of cheap UPS that supports remote management.

I have an old picture of how it looks like that Switch. It seems only Bob realizes what i speak about

It's on my facebook, however talkchess doesn't allow to upload images it seems. Just urls allowed. So let me google for one.

Google for Mellanox MTS3600Q-1BNC

On ebay there is a good photo of it, showing the frontside and the back:

http://www.ebay.com/itm/MTS3600Q-1BNC- ... 230878343

Forget monitoring the switch temperature yourself.

That would mean you need to modify the switch - basically design a new switch. The switch already automatically monitors stuff like fanspeed by the way and turns itself off in case of specific problems.

However there is not 'off button' on the switch. This is internal electronic logics of the switch.

Another issue is logics for the fans that blow to outside of the building and inside into the room.

It seems there is for 40 euro some Relais stuff that can be controlled by rs232 or usb, allowing to monitor up to 8 devices.