Add Dell Hardware OMSA exporter

[galexrt]

Signed-off-by: Alexander Trost galexrt@googlemail.com

This adds my galexrt/dellhw_exporter exporter to the hardware exporter section.
The exporter can export metrics from Dell Hardware using Dell's OpenManage Server Administrator service.

If needed, I can provide the /metrics output in a few days from a Dell server.

[brian-brazil]

Thanks!

I can't see the exporter metrics, but I'm wondering if things like volts and temperature have appropriate units. Also, if things like storage controllers should have a label for the controller in question.

[galexrt]

@brian-brazil Thank you very much for the feedback and the merge!

Volts and temps are exported as floats (e.g.,
https://github.com/galexrt/dellhw_exporter/blob/master/collector/volts.go#L29-L38, https://github.com/galexrt/dellhw_exporter/blob/master/collector/temps.go#L29-L38).
Looking at the other collectors right now, the metrics are mostly exposed as floats right now. "appropriate unit" for the metrics is definitely a point, which I will look into again soon, e.g., that the simpler three way state (0, 1, 2) metrics are using a better type than float.

The storage controllers and alike, have their id added as a label, e.g., https://github.com/galexrt/dellhw_exporter/blob/master/pkg/omreport/omreport.go#L169-L177 the label as added to the created Prometheus metrics.

[SuperQ]

@galexrt By "units", Brian meant "Celsius" or "Fahrenheit", not float. 😄

[galexrt]

Haha. I see, the temperatures are in Celsius. I'll add that to the readme of the temperature collector on the weekend.