Health status reason codes reference

When Azure IoT Operations resources report Degraded or Unavailable health status, they include a reason code that identifies the underlying issue. This reference helps you troubleshoot health status problems more effectively by providing detailed explanations and recommended actions for each reason code.

Note

In the following descriptions, placeholders such as {error}, {e}, or {err} represent the actual error message returned at runtime.

Data flows

Reason code	Description	Recommended action
DataflowTransformSourceSchemaRetrievalFailed	Failed to retrieve the source schema for a transform.	Verify schema reference and schema registry connectivity.
DataflowTransformTargetSchemaRetrievalFailed	Failed to retrieve the target schema for a transform.	Verify schema reference and schema registry connectivity.
DataflowTransformConfigurationFailed	Failed to build the transform pipeline.	Review the data flow transform configuration.
DataflowTransformEnrichDataFailed	Failed to enrich data during transform processing.	Check Broker state store connectivity and dataset configuration.
DataflowTransformSourceChannelClosed	Source input channel closed unexpectedly.	Restart the data flow pipeline if the issue persists.
DataflowTransformMapperFailed	One or more transform steps failed during processing.	Review transform configuration and restart the pipeline.
DataflowGraphModuleDownloadFailed	Failed to download the WASM graph module.	Verify graph artifact availability and registry connectivity.
DataflowGraphModuleDownloadChannelClosed	Internal channel closed during graph artifact download.	Check pod logs and restart the pod.
DataflowGraphInstantiationFailed	WASM runtime failed to instantiate the graph.	Verify module compatibility and resource availability; restart the pod.
DataflowGraphConfigurationFailed	Failed to build the graph pipeline.	Validate graph topology and operation configuration.
DataflowGraphSinkChannelClosed	Output channel closed unexpectedly.	Restart the pod to recover.
DataflowGraphOutputSendFailed	Failed to forward processed messages to the target connector.	Check downstream pipeline and restart the pod.
DataflowGraphProcessingFailed	Unrecoverable error during graph message processing.	Check WASM module logs and restart the pod.
DataflowGraphSourceChannelClosed	Source input channel disconnected unexpectedly.	Verify source connector health and restart the pod.
DataflowGraphSourceSchemaRetrievalFailed	Failed to retrieve source schema for the graph.	Verify schema registry connectivity and configuration.
DataflowGraphNoInputHandle	No input handle found for the graph.	Restart the pod to recover.
DataflowGraphModuleDownloadTimeout	Graph artifact download didn't complete within the timeout.	Verify artifact existence and controller availability.
DataflowGraphModuleRuntimeFault	WASM module panicked during execution.	Check pod logs and backtrace; restart the pod.
DataflowMqttSourceConnectionFailed	MQTT source failed to connect to the broker.	Verify MQTT endpoint, authentication, and network connectivity.
DataflowMqttSourceConfigurationError	MQTT source failed due to a configuration error.	Review MQTT source configuration.
DataflowMqttSourceSubscriptionFailed	MQTT subscription request failed.	Verify topic existence and permissions.
DataflowKafkaSourceConnectionFailed	Kafka source failed to connect to the broker.	Verify broker availability, authentication, and consumer group configuration.
DataflowMqttTargetConfigurationError	MQTT target encountered a fatal configuration error.	Review target configuration and endpoint settings.
DataflowMqttTargetConnectionFailed	MQTT target failed to connect to the broker.	Verify endpoint and authentication settings.
DataflowKafkaTargetConfigurationError	Kafka target failed due to a configuration error.	Review Kafka target configuration.
DataflowKafkaTargetConnectionFailed	Kafka target failed to connect to the broker.	Verify broker availability and authentication.
DataflowKafkaTargetSendFailed	Failed to send data to Kafka.	Check broker health and retry behavior.
DataflowKafkaTargetEndpointUnreachable	Kafka target encountered a fatal client error.	Verify endpoint reachability and restart the client.
DataflowAdxTargetAuthenticationFailed	Failed to authenticate to Azure Data Explorer.	Verify identity and permissions.
DataflowAdxTargetConfigurationError	ADX target encountered a configuration or channel error.	Review target configuration and connectivity.
DataflowAdxTargetSendFailed	Failed to write data to Azure Data Explorer.	Verify ingestion endpoint and retry behavior.
DataflowOtelTargetConfigurationError	Failed to create OpenTelemetry exporter.	Verify OTEL endpoint and configuration.
DataflowOtelTargetProcessingError	Failed to process or batch telemetry data.	Review payload format and OTEL configuration.
DataflowOtelTargetSendFailed	Failed to send telemetry data.	Verify OTEL endpoint reachability.
DataflowObjectStoreTargetAuthenticationFailed	Authentication failed for object storage.	Verify credentials and permissions.
DataflowObjectStoreTargetConfigurationError	Object store configuration is missing or invalid.	Review store configuration.
DataflowObjectStoreTargetSendFailed	Failed to write data to object storage.	Verify endpoint availability and retry behavior.
DataflowDeltaLakeTargetConnectionTimeout	Delta Lake target connection timed out.	Verify endpoint reachability.
DataflowDeltaLakeTargetAuthenticationFailed	Delta Lake authentication failed.	Verify identity and permissions.
DataflowDeltaLakeTargetConfigurationError	Delta Lake configuration is missing or invalid.	Review Delta Lake configuration.
DataflowDeltaLakeTargetSendFailed	Failed to write data to Delta Lake.	Verify storage endpoint and retry behavior.

Assets, devices, and connectors

Reason code	Description	Suggested action
RestConnectorHttpClientCreationFailure	Failed to create REST client: {error}.	Check TLS configuration and authentication settings.
RestConnectorHttpRequestFailure	HTTP request failed after retries: {error}.	Verify endpoint availability and network connectivity.
RestConnectorSchemaGenerationFailure	Failed to create message schema. Response data might be malformed or in an unexpected format.	Validate the response payload format and schema expectations.
RestConnectorWasmProcessingFailure	WASM graph processing failed: {err}.	Check WASM module configuration and input data format.
SseConnectorSchemaGenerationFailure	Failed to create message schema. Event data might be malformed or in an unexpected format.	Validate the event payload and schema configuration.
SseConnectorStreamClosed	SSE client stream closed unexpectedly.	Verify endpoint stability and restart the connector if needed.
SseConnectorStreamError	SSE stream error: {e}.	Check endpoint availability and network connectivity.
MqttConnectorActionNotReady	Management action is not ready: {reason}.	Verify that the management action prerequisites are satisfied.
MqttConnectorPublishFailed	PUBACK indicated failure: {e}.	Check broker connectivity, topic configuration, and permissions.
MqttConnectorPublishFailed	Failed to complete publish: {e}.	Verify MQTT broker availability and authentication settings.
MqttConnectorPublishFailed	Failed to publish: {e}.	Validate topic configuration and broker health.
MqttConnectorSchemaCreationFailed	Failed to create message schema, likely due to malformed data.	Inspect input payload and schema definitions.
MqttConnectorSchemaReportingFailed	Failed to report message schema, likely due to malformed data.	Validate schema reporting configuration and payload format.
MqttConnectorWasmGraphCreationFailed	Failed to create or load WASM graph for data transformation.	Verify WASM graph configuration and availability.
MqttConnectorWasmGraphUpdateFailed	Failed to update WASM graph for data transformation.	Check WASM graph update process and dependencies.
MqttConnectorWasmProcessingFailed	WASM graph failed to process message: {err}.	Inspect WASM module logs and input data.
MqttConnectorWasmSchemaCreationFailed	Failed to create message schema from WASM-processed data.	Validate WASM output and schema expectations.
OpcUaConnectorAssetConnected	The asset is connected and data collection is active.	No action required.
OpcUaConnectorAssetDisconnected	The asset lost connectivity to the OPC UA server.	Check the device endpoint health. If the endpoint is also unavailable, resolve the endpoint issue first. If the endpoint is healthy, review the asset's OPC UA node configuration.
OpcUaConnectorInboundEndpointInvalidConfiguration	The endpoint configuration is invalid and the connector cannot establish a connection.	Review the endpoint configuration in your device resource. Check the endpoint URL, security mode, and authentication settings.
OpcUaConnectorCertificateRejected	The OPC UA server rejected the connector's certificate, or the connector rejected the server's certificate.	Ensure that certificates are properly configured and trusted on both the connector and the OPC UA server.
OpcUaConnectorInboundEndpointConnected	The connector successfully connected to the OPC UA server endpoint.	No action required.
OpcUaConnectorInboundEndpointDisconnected	The connector lost its connection to the OPC UA server endpoint.	Check that the OPC UA server is running and reachable from the edge cluster. Verify network connectivity and firewall rules.
OpcUaConnectorInboundEndpointInvalidConfiguration	The endpoint configuration is invalid and the connector cannot establish a connection.	Review the endpoint configuration in your device resource. Check the endpoint URL, security mode, and authentication settings.
OpcUaConnectorCertificateRejected	The OPC UA server rejected the connector's certificate, or the connector rejected the server's certificate.	Ensure that certificates are properly configured and trusted on both the connector and the OPC UA server.

Broker

Reason code	Description	Suggested action
BrokerReplicaFailed	Broker is in a failed state.	Collect and review the support bundle.
BrokerPartitionFailed	At least one backend replica is down.	Check broker replica health and restart failed replicas if necessary.
BrokerProbeFailed	Probe failed: Failed Operation CONNECT (1/8).	Verify broker connectivity, configuration, and network conditions.

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