In the vCenter Adapter, there is resource attribute hostuuid under the resource group summary.
I have tried the curl expression and able to get the resoirce key object
curl --request POST -u <user_UI_VM>:<pwd_UI_VM> --insecure https://<IP_UI_VM>/HttpPostAdapter/OpenAPIServlet --data "action=lookupResourceByProperty&adapterKindKey=VMWARE&resourceKindKey=HostSystem&metricKey=summary|hostuuid&propertyValues=<HOSTUUID>"
So In API need to define the correct metric key to fetch the resource key.
ResourceKey object of vCenter adapter will be available.
But the issue is that how can we use/combine that resource key object in out custom dashboard.xml? to show up the resource as "HOST SYSTEM" ???