Hi Fabrice -
I see the point of your question - you have Harvest and can't collect data for an ONTAP 9.x cluster or from an OCUM 7.x server. The versions are the key - I've had similar issues as new ONTAP/OCUM versions get released.
Harvest uses a series of template files that are specific to the version being collected from. The template files contain details of what counters to collect from each version. The Harvest I first installed supported OCUM 6.3 for instance, and when I installed OCUM 6.4, Harvest could no longer find a matching template. Same held true when I bumped OCUM 6.4 to OCUM 7.0 RC1.
Template files are located at /opt/harvest/template/default as I recall - I don't have an installed Harvest to check at the moment. For example, one such template file is /opt/harvest/template/default/ocum-6.4.0.conf which you see lists a product ocum and a version 6.4.0. The quick and dirty solution is to simply copy an existing template to a new template with the corect version - for instance
cp /opt/harvest/template/default/ocum-6.4.0.conf /opt/harvest/template/default/ocum-7.0.0.conf
I used that copy to get my OCUM 7.0 up and running without issue. Copy an 8.3 ONTAP template with a 9.0 name to get a similar result for collecting from the Cluster. While the template won't colelct anything new, and it might try to colelct some counters that no longer exist or were modified, it should collect enough to get things started. I hadn't hyet updated to 9.0 when I was working with Harvest at a previous position so I can't comment how well the 8.3 cDoT template covers 9.0 ONTAP. The OCUM template worked perfectly - all the standard dashboards for Harvest/Grafana had the data they need.
The templating facility is really nice by the way. You can build custom templates for specific circumstances - for instance a particular set of controllers need to grab only very basic data but others need additional specific performance data not typically collected. Using the Harvest configuration file you can direct controllers based on a number of properties to non-default collection templates. It's really a well thought out design for data analysis.
Hope this helps.
Bob Greenwald
Senior Systems Engineer | cStor
NCIE SAN ONTAP, Data Protection
Kudos and accepted solutions are always appreciated.