Hi, may this would help.
I have the same error... Drive me crazy for a log time ... not harmful indeed but very annoying. This is my situation:
Added this template: \NAS\QNAP\FileSystem (right from the template in the Server container )
With the same variables as FileSystem template in \Server container:
This works: i can see the graph and all that stuff in the device view. But with the warning on events tab of the Zenoss server:
The threshold high disk usage in template /zport/dmd/Devices/Server/rrdTemplates/FileSystem has caused an exception.
Then this morning I tried this: I changed data sources names in my template (and thresholds reference accordingly):
That seems to help...
Would this be the solution?