The UCS Dashboard Client is based on the popular Prometheus Node Exporter, which exposes a wide variety of hardware- and kernel-related metrics.
Additionally the App installs a collector for UCS specific metrics like UCS version and role.
The "UCS Dashboard Client" App needs to be installed on all UCS servers which should be available in the "UCS Dashboard" App. The "UCS Dashboard" App itself needs to installed on one of the UCS servers.