Page History

...

If GetTelemetrySubscriptionsResponse.RequestedMetrics indicates that no metrics are desired (RequestedMetrics is Null) the client should send a new GetTelemetrySubscriptionsResponse after the  the PushIntervalMs has expired.

If GetTelemetrySubscriptionsResponse.RequestedMetrics is non-empty but does not match any metrics the client provides then the client should PushTelemetryRequests at the indicated PushIntervalMs interval with an empty metrics blob. This is needed so that a broker side metrics plugin can differentiate between non-responsive or buggy clients and clients that don't have metrics matching the subscription set.

Connection selection

The client may send telemetry requests to any broker, but shall prefer using an already available connection rather than creating a new connection - to keep the number of cluster connections down.

...