Metrics for MQTT broker
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MQTT broker provides a set of observability metrics that you can use to monitor and analyze the health of your solution. This article describes the available metrics for MQ and the MQ cloud connector.
MQ metrics
| Metric name | Definition |
|---|---|
| aio_mq_publishes_received | On the front end, represents how many incoming publish packets have been received from clients. For the backend, represents how many internal messages have been sent from the front end nodes. |
| aio_mq_publishes_sent | On the front end, represents how many outgoing publish packets have been sent to clients. If multiple clients are subscribed to the same topic, this metric counts each message sent, even if they have the same payload. The metric does not count ack packets. For the backend, this metric represents how many internal messages have been sent to the front end nodes. |
| aio_mq_authorization_allow | Counts how many times an authenticated client has successfully authorized. This should always be less than or equal to authentication_successes. |
| aio_mq_authorization_deny | Counts how many times an authenticated client has been denied. This should always be less than or equal to authentication_successes. |
| aio_mq_total_sessions | On the front end and single node broker, represents how many client sessions there are. The metric does not include disconnected persistent sessions, because a client might reconnect to a different front end node. For the backend, this represents its connections to the other nodes in its chain. On the operator, represents how many front and back end nodes are connected. For the authentication server, represents how many front end workers are connected (one per front end per thread). |
| aio_mq_store_total_sessions | This is a back end specific metric that represents how many sessions are managed by the backend's chain. Backend nodes in the same chain should report the same number of sessions, and the sum of each chain should equal the sum of the front end's total_sessions. |
| aio_mq_connected_sessions | Similar to aio_mq_total_sessions, except that it represents only sessions that have an active connection. |
| aio_mq_backpressure_packets_rejected | This is a count of how many packets rejected in MQTT back pressure. |
| aio_mq_store_connected_sessions | Similar to aio_mq_store_total_sessions, except that it only refers to sessions that have an active connection. If is_persistent is false, this should be equal to total sessions. |
| aio_mq_total_subscriptions | On the front end, represents how many subscriptions the currently connected sessions have. This does not include disconnected persistent sessions, because a client might reconnect to a different front end node. For the backend, represents other nodes in its chain connecting to it. On the operator, this represents the front and back end nodes. For the authentication server, this represents how many front end workers are connected (one per front end per thread). |
| aio_mq_store_total_subscriptions | This is a back end specific metric that represents how many subscriptions are managed by the backend's chain. Backend nodes in the same chain should report the same number of subscriptions. This will not necessarily match the front end's total_subscriptions, since this metric tracks disconnected persistent sessions as well. |
| aio_mq_authentication_successes | Counts how many times a client has successfully authenticated. |
| aio_mq_authentication_failures | Counts how many times a client has failed to authenticate. For an errorless authentication server: authentication_successes + authentication_failures = publishes_received = publishes_sent. |
| aio_mq_authentication_deny | Counts how many times a client has denies to authenticate. |
| aio_mq_number_of_routes | Counts number of routes. |
| aio_mq_connect_route_replication_correctness | Describes if a connection request from a self test client is replicated correctly along a specific route. |
| aio_mq_connect_latency_route_ms | Describes the time interval between a self test client sending a CONNECT packet and receiving a CONNACK packet. This metric is generated per route. The metric is generated only if a CONNECT is successful. |
| aio_mq_connect_latency_last_value_ms | An estimated p99 of connect_latency_route_ms. |
| aio_mq_connect_latency_mu_ms | The mean value of connect_latency_route_ms. |
| aio_mq_connect_latency_sigma_ms | The standard deviation of connect_latency_route_ms. |
| aio_mq_subscribe_route_replication_correctness | Describes if a subscribe request from a self test client is replicated correctly along a specific route. |
| aio_mq_subscribe_latency_route_ms | Describes time interval between a self test client sending a SUBSCRIBE packet and receiving a SUBACK packet. This metric is generated per route. The metric is generated only if a SUBSCRIBE is successful. |
| aio_mq_subscribe_latency_last_value_ms | An estimated p99 of subscribe_latency_route_ms. |
| aio_mq_subscribe_latency_mu_ms | The mean value of subscribe_latency_route_ms. |
| aio_mq_subscribe_latency_sigma_ms | The standard deviation of subscribe_latency_route_ms. |
| aio_mq_unsubscribe_route_replication_correctness | Describes if a unsubscribe request from a self test client is replicated correctly along a specific route. |
| aio_mq_unsubscribe_latency_route_ms | Describes the time interval between a self test client sending a UNSUBSCRIBE packet and receiving a UNSUBACK packet. This metric is generated per route. The metric is generated only if a UNSUBSCRIBE is successful. |
| aio_mq_unsubscribe_latency_last_value_ms | An estimated p99 of unsubscribe_latency_route_ms. |
| aio_mq_unsubscribe_latency_mu_ms | The mean value of unsubscribe_latency_route_ms. |
| aio_mq_unsubscribe_latency_sigma_ms | The standard deviation of subscribe_latency_route_ms. |
| aio_mq_publish_route_replication_correctness | Describes if an unsubscribe request from a self test client is replicated correctly along a specific route. |
| aio_mq_publish_latency_route_ms | Describes the time interval between a self test client sending a PUBLISH packet and receiving a PUBACK packet. This metric is generated per route. The metric is generated only if a PUBLISH is successful. |
| aio_mq_publish_latency_last_value_ms | An estimated p99 of publish_latency_route_ms. |
| aio_mq_publish_latency_mu_ms | The mean value of publish_latency_route_ms. |
| aio_mq_publish_latency_sigma_ms | The standard deviation of publish_latency_route_ms. |
| aio_mq_backend_replicas | This set of metrics tracks the overall state of the broker. These are paired metrics, where the first metric represents the desired state and the second metric represents the current state. These metrics show how many pods are healthy from the broker's perspective, and might not match with what k8s reports. |
| aio_mq_backend_replicas_current | This set of metrics tracks the overall state of the broker. These are paired metrics, where the first metric represents the desired state and the second metric represents the current state. These metrics show how many pods are healthy from the broker's perspective, and might not match with what k8s reports. |
| aio_mq_frontend_replicas | This set of metrics tracks the overall state of the broker. These are paired metrics, where the first metric represents the desired state and the second metric represents the current state. These metrics show how many pods are healthy from the broker's perspective, and might not match with what k8s reports. |
| aio_mq_frontend_replicas_current | This set of metrics tracks the overall state of the broker. These are paired metrics, where the first metric represents the desired state and the second metric represents the current state. These metrics show how many pods are healthy from the broker's perspective, and might not match with what k8s reports. |
| aio_mq_payload_bytes_received | Counts the message payload in bytes received. |
| aio_mq_payload_bytes_sent | Counts the message payload in bytes sent. |
| aio_mq_payload_check_latency_last_value_ms | An estimated p99 of latency check of the last value. |
| aio_mq_payload_check_latency_mu_ms | The mean value of latency check. |
| aio_mq_payload_check_latency_sigma_ms | The standard deviation of latency of the payload. |
| aio_mq_payload_check_total_messages_lost | The count of payload total message lost. |
| aio_mq_payload_check_total_messages_receieved | The count of total number of message received. |
| aio_mq_payload_check_total_messages_sent | The count of total number of message sent. |
| aio_mq_ping_correctness | Describes whether the ping from self-test client works correctly. |
| aio_mq_ping_latency_last_value_ms | An estimated p99 of ping operation of the last value. |
| aio_mq_ping_latency_mu_ms | The mean value of ping check. |
| aio_mq_ping_latency_route_ms | The ping latency in milliseconds for a specific route. |
| aio_mq_ping_latency_sigma_ms | The standard deviation of latency of the ping operation. |
| aio_mq_publishes_processed_count | Describes the processed counts of message published. |
| aio_mq_publishes_received_per_second | Counts the number of published messages received per second. |
| aio_mq_publishes_sent_per_second | Counts the number of sent messages received per second. |
| aio_mq_qos0_messages_dropped | Counts QoS0 messages dropped. |
| aio_mq_state_store_deletions | Counts the number of messages deleted that are stored in the system. |
| aio_mq_state_store_insertions | Counts the number of messages inserted that are stored in the system. |
| aio_mq_state_store_modifications | Counts the number of messages modified that are stored in the system. |
| aio_mq_state_store_retrievals | Counts the number of messages retrieved that are stored in the system. |
| aio_mq_store_retained_bytes | Contains the number in bytes of messages retained in the system. |
| aio_mq_store_retained_messages | Contains the number of messages retained in the system. |
| aio_mq_store_will_bytes | Contains the bytes that cover the payload of the will messages in the system. |
Cloud connector metrics
MQTT Bridge
| Metric name | Definition |
|---|---|
| aio_mq_mqttbridge_active_connections_count | Count of active connection to the Azure Event Grid MQTT broker. |
| aio_mq_mqttbridge_number_of_routes | Count of routes to the Azure Event Grid MQTT broker. |
| aio_mq_mqttbridge_publish_bytes | The number in bytes of messaged published to the Azure Event Grid MQTT broker. |
| aio_mq_mqttbridge_publishes_processed_count | Count of processed messages published to the Azure Event Grid MQTT broker. |
Event Hubs and Kafka
| Metric name | Definition |
|---|---|
| aio_mq_kafka_cloud_bytes_received | Messages in bytes received from MQTT broker to Azure Event Hubs. |
| aio_mq_kafka_cloud_bytes_sent | Messages in bytes sent from Azure Event Hubs to MQTT broker. |
| aio_mq_kafka_cloud_publishes_received | Count of messages published from MQTT broker to Azure Event Hubs. |
| aio_mq_kafka_cloud_publishes_sent | Count of messages from Azure Event Hubs to MQTT broker. |
| aio_mq_kafka_dmqtt_bytes_received | Messages in bytes received from Azure Event Hubs to MQTT broker. If the connector is online, this metric should equal the value of aio_mq_kafka_cloud_bytes_sent. |
| aio_mq_kafka_dmqtt_bytes_sent | Messages in bytes published from MQTT broker to Azure Event Hubs. If the connector is online, this metric should equal the value of aio_mq_kafka_cloud_bytes_received. |
| aio_mq_kafka_dmqtt_publishes_received | Counts of messages received from Azure Event Hubs to MQTT broker. If the connector is online, this metric should equal the value of aio_mq_kafka_cloud_publishes_sent. |
| aio_mq_kafka_dmqtt_publishes_sent | Counts of messages published from MQTT broker to Azure Event Hubs. If the connector is online, this metric should equal the value of aio_mq_kafka_cloud_publishes_received. |
Data Lake
| Metric name | Definition |
|---|---|
| aio_mq_datalake_cloud_publishes_sent | Count of messages published from Azure Data Lake to MQTT broker. |
| aio_mq_datalake_dmqtt_bytes_received | The number in bytes of messages that MQTT broker received from Azure Data Lake. |
| aio_mq_datalake_dmqtt_publishes_received | The number in bytes of messages published from MQTT broker to Azure Data Lake. |