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To avoid the receiving broker’s metrics rate-limiter discarding this out-of-profile push, the PushTelemetryRequest.Terminating
field must be set to true. A broker must only allow one such unthrottled metrics push for each combination of client instance ID and SubscriptionId.
In the event that the client's metric subscription has changed and the final metrics push fails with error code UNKNOWN_SUBSCRIPTION_ID
, the terminating client can choose to obtain a new subscription ID by sending a GetTelemetrySubscriptionsRequest and then immediately sending a PushTelemetryRequest with the Terminating flag set to true, or it can choose to abandon sending a final metrics push.
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