Temperature Sensor

A reoccurring problem with the air conditioning system that cools the helios cluster is that it occasionally just shuts off. We do not own the unit, so we cannot fix the problem ourselves. Until the problem is fixed, we have to have some way of monitoring the temperature of the room. If it gets too hot, we want to shut down all of the machines to prevent damage. While we could use the temperature sensor of the IPMI cards, there are problems associated with that that made it unfeasible.

In my quest to find a USB temperature sensor that worked under Linux, I came across a tutorial for making a Linux USB driver for the Go!Temp USB device. The device itself can be purchased at the manufacturer's website.

We purchased this thermometer and, using the driver created in that tutorial, connected it to our admin machine. With all of the nodes OFF, it is 85°F in the room at the moment. In other words, it's way too dang hot in there.

Eventually, we'll have an automated system that emails us after the temperature reaches a certain threshold, and shuts off the machines at another threshold. And, the sensor will probably be moved to the gateway machine. No point in having extra load be put on the admin machine.

I think the ldusb driver can be used (instead of the one created using that tutorial), but I personally do not know how to use it, so this works for our needs for now.