To create a Fabric Group – login using the configurationadmin. As mentioned before – I am using the default tenant (which is supported now).
Navigate to Infrastructure > Endpoints > Fabric Groups
Click 
Enter a descriptive name, add a Fabric Admin (here again I am using my admin group) and select the cluster you want to give permissions to. Here I only have one. I also add the local configurationadmin.
Note: IF you don’t see your cluster yet, then the data collection has not yet finished. I forced the data collection by simply restarting my IIS box. I am still in the process to find out if there is a way to do this manually. A data collection can be executed manually once you got your Compute Resources, but to get those, you need the Fabric Group – bit of a catch 22 ..
If you have Endpoints pointing to external systems (such as Cisco UCS Manager), you can initiate a collection on the Endpoint – but for agent based endpoints, such as vSphere – you don’t have that option.
Anyway, here I do have my resources and gave it a name.
Click OK
That’s it .. Easy …