Setup for Python 3.x to Query LM looking at Arista Voltage Sensors - Just PowerSupply

ok, easy peasy. 

The strategy mentioned before is still the recommended way. You'd clone the datasource and modify the new datasource to include a discovery filter where the sensor_owner (which is the attribute that determines instance group membership) starts with "PowerSupply". There's not a "starts with" option, but there's a "RegexMatch" option. So it would look like this:

This should result is basically the same datasource as you had before, but will only discover the instances where the sensor_owner is a power supply. Use the "Test Active Discovery" button to make sure you're getting the right instances. You might not need the "auto." at the beginning, i can't test without an arista device.

Once you've got that new clone working, set your threshold on the volt datapoint.

Once that's all working, there's no need to monitor those instances with the old datasource, so go add a filter that filters them out of that one. Something like this:

I think I understand .

But - this will duplicate the devices that are being monitored - adding more devices to our license -
One of the devices will be able to alert on the powersupply voltage if it is low -
The other would have everything else being monitored.

We still need the other objects being monitored - like the traffic on the interfaces and other items like BGP etc. All the normal stuff.
If I do the RegexNotMatch - then won't it exclude all the other items from being monitored?

It will add more datasources to the same device, not add more devices. 

Before (top) and after (bottom). You are licensed by device, not by instance. We count the number of devices your collector talks to, not how much data we gather from that device. Besides, the total number of instances isn't actually changing.

OK - thanks for helping me understand the process. I see that I also have the ability to set the alert. 

As an aside -
I noticed that the allowed ranges were 0 to 207 volts. - - I'm seeing actual voltage values higher than 207 though - it is a 240 volt source.
In rolling through the devices - I see some at 210 for instance. 

I'm not seeing a max on the datapoint definition nor on the axis in any of the graph definitions. Normally, if you don't set a max, it just auto adjusts to a decent height so everything is visible on the graph. You can hard code that, or leave it automatic.