# Broker and Controller Metrics This topic describes JMX metrics for Kafka brokers, KRaft mode, and controllers. These metrics are useful for monitoring the health and performance of your Kafka cluster. For information about how to configure JMX, see [Configure JMX for Monitoring](configure-jmx.md#configure-jmx). ## Search for a metric

## Broker metrics There are many metrics reported at the broker and controller level that can be monitored and used to troubleshoot issues with your cluster. At minimum, you should monitor and set alerts on `ActiveControllerCount`, `OfflinePartitionsCount`, and `UncleanLeaderElectionsPerSec`. ### AtMinIsr MBean: `kafka.cluster:type=Partition,topic={topic},name=AtMinIsr,partition={partition}` : The number of partitions whose in-sync replicas count is equal to the `minIsr` value. ### Bandwidth quota MBean: `kafka.server:type={Produce|Fetch},user={userName},client-id={clientId}` : Use the attributes of this metric to measure the bandwidth quota. This metric has the following attributes:
- `throttle-time`: the amount of time in milliseconds the client was throttled. Ideally = 0. - `byte-rate`: the data produce/consume rate of the client in bytes/sec. - For (`user`, `client-id`) quotas, specify both `user` and `client-id`. - If a `per-client-id` quota is applied to the client, do not specify `user`. - If a `per-user` quota is applied, do not specify `client-id`. ### BrokerRegistrationState MBean: `kafka.controller:type=KafkaController,name=BrokerRegistrationState,broker=X` : A per-broker metric that displays the following state values: : - `10` indicates that the broker is fenced - `20` indicates that the broker is in controlled shutdown - `30` indicates that the broker is active
This metric is added when a broker registers and is removed when it unregisters. This state is derived from the registration records contained in the metadata log. ### BytesInPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=BytesInPerSec,topic={topicName}` : The incoming byte rate from clients, per topic. Omitting ‘topic={…}’ will yield the all-topic rate. ### BytesOutPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=BytesOutPerSec,topic={topicName}` : The outgoing byte rate to clients per topic. Omitting ‘topic={…}’ will yield the all-topic rate. ### BytesRejectedPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=BytesRejectedPerSec,topic={topicName}` : The rejected byte rate per topic, due to the record batch size being greater than `max.message.bytes` configuration. Omitting ‘topic={…}’ will yield the all-topic rate. ### clientSoftwareName/clientSoftwareVersion

MBean: kafka.server:clientSoftwareName=(name),clientSoftwareVersion=(version),
listener=(listener),networkProcessor=(processor-index),type=(type)

The name and version of client software in the brokers. For example, the Kafka 2.4 Java client produces the following MBean on the broker: ```none kafka.server:clientSoftwareName=apache-kafka-java,clientSoftwareVersion=2.4.0,listener=PLAINTEXT,networkProcessor=1,type=socket-server-metrics ``` ### connection-count

MBean: kafka.server:type=socket-server-metrics,listener={listener_name},networkProcessor={#},
name=connection-count

The number of currently open connections to the broker. ### connection-creation-rate

MBean: kafka.server:type=socket-server-metrics,listener={listener_name},networkProcessor={#},
name=connection-creation-rate

The number of new connections established per second. ### consumer-lag-offsets

MBean: kafka.server:type=tenant-metrics,member={mbrId},topic={tpcName},consumer-group={gpName},
partition={Id},client-id={cliId},group-protocol={grpProtocol}

Attribute: consumer-lag-offsets

This metric is the difference between the last offset stored by the broker and the last committed offset for a specific consumer group name, client ID, member ID, partition ID, topic name, and group protocol. The group protocol specifies the rebalance protocol used by the consumer group, currently either `classic` or `consumer`. For more information about the rebalance protocols, see [Consumer Rebalance Protocols](/kafka/design/consumer-design.html#consumer-rebalance-protocols-and-partition-assignments). This metric provides the consumer lag in offsets only and does not report latency. In addition, it is not reported for any groups that are not alive or are empty. To enable this metric, you must set the following server properties. ```none confluent.consumer.lag.emitter.enabled=true # default is false confluent.consumer.lag.emitter.interval.ms=60000 # default is 60000 ``` For more information about this metric, see [Monitor Consumer Lag in Confluent Platform](../monitor/monitor-consumer-lag.md#consumer-lag). ### share-lag-offsets

MBean: kafka.server:type=tenant-metrics,group-protocol=share,partition={partitionid},
group-id={sharegroupid},topic={topicname}

Attribute: share-lag-offsets

This metric represents the number of offsets in a partition that are not delivery complete for a specific share group ID, partition ID, topic name, and group protocol (share). The group protocol specifies the rebalance protocol used by the group, currently `share`. This metric reports share lag in offsets only and does not report latency. In addition, it is not reported for any groups that are not alive or are empty. To enable share lag, set `confluent.share.lag.calculator.enabled` to `true`. This property enables share lag monitoring, and is `false` by default. This high-cardinality metric could impact systems consuming it. Additionally, `org.apache.kafka.common.metrics.JmxReporter` must be added as part of the `metric.reporters` broker configuration to see the metric in JMX. ### ConsumerLag

MBean: kafka.server:type=FetcherLagMetrics,name=ConsumerLag,clientId=([-.\\w]+),
topic={topicName},partition=([0-9]+)

The lag in number of messages per follower replica. This is useful to know if the replica is slow or has stopped replicating from the leader and if the associated brokers need to be removed from the In-Sync Replicas list. ### ControlledShutdownBrokerCount MBean: `kafka.controller:type=KafkaController,name=ControlledShutdownBrokerCount` : The number of brokers currently in controlled shutdown. ### CurrentControllerId MBean: `kafka.server:type=MetadataLoader,name=CurrentControllerId` : Outputs the ID of the current controller, or -1 if none is known. Reports the current controller ID on broker and controller nodes. ### ElectionFromEligibleLeaderReplicasPerSec MBean: `kafka.controller:type=ControllerStats,name=ElectionFromEligibleLeaderReplicasPerSec` : The Eligible Leader Replicas (ELR) election rate. It increments by one when a leader is elected. ### ElectionRateAndTimeMs MBean: `kafka.controller:type=ControllerStats,name=LeaderElectionRateAndTimeMs` : The broker leader election rate and latency in milliseconds. This is non-zero when there are broker failures. ### FailedFetchRequestsPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=FailedFetchRequestsPerSec` : The fetch request rate for requests that failed. ### FailedProduceRequestsPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=FailedProduceRequestsPerSec` : The produce request rate for requests that failed. ### InSyncReplicasCount MBean: `kafka.cluster:type=Partition,topic={topic},name=InSyncReplicasCount,partition={partition}` : A gauge metric that indicates the in-sync replica count per topic partition leader. ### InvalidMagicNumberRecordsPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=InvalidMagicNumberRecordsPerSec` : The message validation failure rate due to an invalid magic number. This should be 0. ### InvalidMessageCrcRecordsPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=InvalidMessageCrcRecordsPerSec` : The message validation failure rate due to incorrect Crc checksum ### InvalidOffsetOrSequenceRecordsPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=InvalidOffsetOrSequenceRecordsPerSec` : The message validation failure rate due to non-continuous offset or sequence number in batch. Normally this should be 0. ### IsrExpandsPerSec MBean: `kafka.server:type=ReplicaManager,name=IsrExpandsPerSec` : Measures the expansion of in-sync replicas per second. When a broker is brought up after a failure, it starts catching up by reading from the leader. Once it is caught up, it gets added back to the ISR. ### IsrShrinksPerSec MBean: `kafka.server:type=ReplicaManager,name=IsrShrinksPerSec` : Measures the reduction of in-sync replicas per second. If a broker goes down, ISR for some of the partitions will shrink. When that broker is up again, ISR will be expanded once the replicas are fully caught up. Other than that, the expected value for both ISR shrink rate and expansion rate is 0. ### LeaderCount MBean: `kafka.server:type=ReplicaManager,name=LeaderCount` : The number of leaders on this broker. This should be mostly even across all brokers. If not, set `auto.leader.rebalance.enable` to `true` on all brokers in the cluster. ### linux-disk-read-bytes MBean: `kafka.server:type=KafkaServer,name=linux-disk-read-bytes` : The total number of bytes read by the broker process, including reads from all disks. The total doesn’t include reads from page cache. **Available only on Linux-based systems.** ### linux-disk-write-bytes MBean: `kafka.server:type=KafkaServer,name=linux-disk-write-bytes` : The total number of bytes written by the broker process, including writes from all disks. **Available only on Linux-based systems.** ### MaxLag MBean: `kafka.server:type=ReplicaFetcherManager,name=MaxLag,clientId=Replica` : The maximum lag, across all follower replicas fetched by this broker, between a follower’s log end offset and the leader’s log end offset. Each broker reports this metric. Reassigning partitions causes this metric to jump to a value corresponding to the size of the partition, then slowly decay as the reassignment progresses. If this value slowly rises rather than falls over time, the replication throttle is set too low. For more information, see [Metrics for monitoring a rebalance](../clusters/sbc/index.md#sbc-monitoring-metrics). ### MessageConversionsPerSec

MBean: kafka.server:type=BrokerTopicMetrics,name={Produce|Fetch}MessageConversionsPerSec,
topic=([-.\\w]+)

The message format conversion rate, for Produce or Fetch requests, per topic. Omitting ‘topic={…}’ will yield the all-topic rate. ### MessagesInPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=MessagesInPerSec,topic={topicName}` : The incoming message rate per topic. Omitting ‘topic={…}’ will yield the all-topic rate. ### NoKeyCompactedTopicRecordsPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=NoKeyCompactedTopicRecordsPerSec` : The message validation failure rate due to no key specified for compacted topic. This should be 0. ### PartitionCount MBean: `kafka.server:type=ReplicaManager,name=PartitionCount` : The number of partitions on this broker. This should be mostly even across all brokers. ### PartitionsWithLateTransactionCount MBean: `kafka.server:type=ReplicaManager,name=PartitionsWithLateTransactionsCount` : The number of partitions that have open transactions with durations exceeding the `transaction.max.timeout.ms` property value set on the broker. ### PurgatorySize (fetch) MBean: `kafka.server:type=DelayedOperationPurgatory,delayedOperation=Fetch,name=PurgatorySize` : The number of requests waiting in the fetch purgatory. This is high if consumers use a large value for `fetch.wait.max.ms` ### PurgatorySize (produce) MBean: `kafka.server:type=DelayedOperationPurgatory,delayedOperation=Produce,name=PurgatorySize` : The number of requests waiting in the producer purgatory. This should be non-zero when `acks=all` is used on the producer. ### queue-size MBean: `kafka.server:type=Produce,name=queue-size` : The number of producer clients currently being throttled. The value can be any number greater than or equal to `0`.
#### IMPORTANT For monitoring quota applications and throttled clients, use the [Bandwidth quota](#bandwidth-quota) and [Request quota](#request-quota) metrics. ### ReassigningPartitions MBean: `kafka.server:type=ReplicaManager,name=ReassigningPartitions` : The number of reassigning partitions. ### ReassignmentBytesInPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=ReassignmentBytesInPerSec` : The incoming byte rate of reassignment traffic. ### ReassignmentBytesOutPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=ReassignmentBytesOutPerSec` : The outgoing byte rate of reassignment traffic. ### ReplicasCount MBean: `kafka.cluster:type=Partition,topic={topic},name=ReplicasCount,partition={partition}` : A gauge metric that indicates the replica count per topic partition leader. ### ReplicationBytesInPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=ReplicationBytesInPerSec,topic={topicName}` : The incoming byte rate from other brokers per topic. Omitting ‘topic={…}’ will yield the all-topic rate. ### ReplicationBytesOutPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=ReplicationBytesOutPerSec` : The byte-out rate to other brokers. ### Request quota MBean: `kafka.server:type=Request,user={userName},client-id={clientId}` : Use the attributes of this metric to measure request quota. This metric has the following attributes:
- `throttle-time`: the amount of time in milliseconds the client was throttled. Ideally = 0. - `request-time`: the percentage of time spent in broker network and I/O threads to process requests from client group. - For (`user`, `client-id`) quotas, specify both `user` and `client-id`. - If a `per-client-id` quota is applied to the client, do not specify `user`. - If a `per-user` quota is applied, do not specify `client-id`. ### RequestHandlerAvgIdlePercent MBean: `kafka.server:type=KafkaRequestHandlerPool,name=RequestHandlerAvgIdlePercent` : The average fraction of time the request handler threads are idle. Values are between `0` meaning all resources are used and `1` meaning all resources are available. ### TimeSinceLastHeartbeatReceivedMs MBean: `kafka.controller:type=KafkaController,name=TimeSinceLastHeartbeatReceivedMs,broker=X` : A per-broker metric that reports the time in milliseconds since the last heartbeat received by the controller.
- The maximum value is the heartbeat session timeout limit. This is because the map whose values are being exposed removes the broker’s contact time when the broker gets fenced. - The default session timeout is nine seconds. - This metric is only reported in the active controller because it’s soft state is contained in the BrokerHeartbeatTracker.
This metric is added when a broker registers and removed when it unregisters. ### TotalFetchRequestsPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=TotalFetchRequestsPerSec` : The fetch request rate per second. ### TotalProduceRequestsPerSec MBean: `kafka.server:type=BrokerTopicMetrics,name=TotalProduceRequestsPerSec` : The produce request rate per second. ### UncleanLeaderElectionsPerSec MBean: `kafka.controller:type=ControllerStats,name=UncleanLeaderElectionsPerSec` : The unclean broker leader election rate. Should be 0. ### UnderMinIsr MBean: `kafka.cluster:type=Partition,topic={topic},name=UnderMinIsr,partition={partition}` : The number of partitions whose in-sync replicas count is less than `minIsr`. These partitions will be unavailable to producers who use `acks=all`. ### UnderMinIsrPartitionCount MBean: `kafka.server:type=ReplicaManager,name=UnderMinIsrPartitionCount` : The number of partitions whose in-sync replicas count is less than `minIsr`. ### UnderReplicated MBean: `kafka.cluster:type=Partition,topic={topic},name=UnderReplicated,partition={partition}` : The number of partitions that are under replicated meaning the number of in-sync replicas is less than the replica count. ### UnderReplicatedPartitions MBean: `kafka.server:type=ReplicaManager,name=UnderReplicatedPartitions` : The number of under-replicated partitions (| ISR | < | current replicas |). Replicas that are added as part of a reassignment will not count toward this value. Alert if the value is greater than 0. ## KRaft broker metrics These metrics are only produced for a broker when running in KRaft mode. ### last-applied-record-lag-ms MBean: `kafka.server:type=broker-metadata-metrics,name=last-applied-record-lag-ms` : The difference between now and the timestamp of the last record from the cluster metadata partition that was applied by the broker. ### last-applied-record-offset MBean: `kafka.server:type=broker-metadata-metrics,name=last-applied-record-offset` : The offset of the last record from the cluster metadata partition that was applied by the broker. ### last-applied-record-timestamp MBean: `kafka.server:type=broker-metadata-metrics,name=last-applied-record-timestamp` : The timestamp of the last record from the cluster metadata partition that was applied by the broker. ### metadata-apply-error-count MBean: `kafka.server:type=broker-metadata-metrics,name=metadata-apply-error-count` : The number of errors encountered by the `BrokerMetadataPublisher` while applying a new `MetadataImage` based on the latest `MetadataDelta`. ### metadata-load-error-count MBean: `kafka.server:type=broker-metadata-metrics,name=metadata-load-error-count` : The number of errors encountered by the `BrokerMetadataListener` while loading the metadata log and generating a new `MetadataDelta` based on it. ## KRaft Quorum metrics The set of metrics that allow monitoring of the KRaft quorum and metadata log. These metrics are reported on both controllers and brokers in a KRaft cluster. ### CurrentMetadataVersion MBean: `kafka.server:type=MetadataLoader,name=CurrentMetadataVersion` : Outputs the feature level of the current effective metadata version. ### HandleLoadSnapshotCount MBean: `kafka.server:type=MetadataLoader,name=HandleLoadSnapshotCount` : The total number of times we have loaded a KRaft snapshot since the process was started. ### MetadataLoaderIdleRatio MBean: `kafka.server:type=MetadataLoader,name=MetadataLoaderIdleRatio` : The fraction of time the metadata loader thread spends waiting for new metadata images, where 0.0 means the thread is always busy and 1.0 means the thread is always idle. Use this metric to diagnose delays in how quickly a broker applies updates from the KRaft controller. Following are attributes of the `kafka.server:type=raft-metrics` MBean: ### append-records-rate MBean: `kafka.server:type=raft-metrics` Attribute: `append-records-rate` : The average number of records appended per sec by the leader of the raft quorum. ### commit-latency-avg MBean: `kafka.server:type=raft-metrics` Attribute: `commit-latency-avg` : The average time in milliseconds to commit an entry in the raft log. ### commit-latency-max MBean: `kafka.server:type=raft-metrics` Attribute: `commit-latency-max` : The maximum time in milliseconds to commit an entry in the raft log. ### current-epoch MBean: `kafka.server:type=raft-metrics` Attribute: `current-epoch` : The current quorum epoch. ### current-leader MBean: `kafka.server:type=raft-metrics` Attribute: `current-leader` : The current quorum leader’s id; -1 indicates unknown. ### current-state MBean: `kafka.server:type=raft-metrics` Attribute: `current-state` : The current state of this member; possible values are leader, candidate, voted, follower, unattached, observer. ### current-vote MBean: `kafka.server:type=raft-metrics` Attribute: `current-vote` : The current voted leader’s id; -1 indicates not voted for anyone. ### election-latency-avg MBean: `kafka.server:type=raft-metrics` Attribute: `election-latency-avg` : The average time in milliseconds spent on electing a new leader. ### election-latency-max MBean: `kafka.server:type=raft-metrics` Attribute: `election-latency-max` : The maximum time in milliseconds spent on electing a new leader. ### fetch-records-rate MBean: `kafka.server:type=raft-metrics` Attribute: `fetch-records-rate` : The average number of records fetched from the leader of the raft quorum. ### high-watermark MBean: `kafka.server:type=raft-metrics` Attribute: `high-watermark` : The high watermark maintained on this member; -1 if it is unknown. ### log-end-epoch MBean: `kafka.server:type=raft-metrics` Attribute: `log-end-epoch` : The current raft log end epoch. ### log-end-offset MBean: `kafka.server:type=raft-metrics` Attribute: `log-end-offset` : The current raft log end offset. ### number-of-voters MBean: `kafka.server:type=raft-metrics` Attribute: `number-of-voters` : The number of voters in the KRaft quorum, which equals the total number of registered KRaft controller nodes. Both brokers and controllers report this metric. ### number-unknown-voter-connections MBean: `kafka.server:type=raft-metrics` Attribute: `number-unknown-voter-connections` : The number of unknown voters whose connection information is not cached. This value of this metric is always 0. ### poll-idle-ratio-avg MBean: `kafka.server:type=raft-metrics` Attribute: `poll-idle-ratio-avg` : The average fraction of time the client’s poll() is idle as opposed to waiting for the user code to process records. ### LatestSnapshotGeneratedAgeMs MBean: `kafka.server:type=SnapshotEmitter,name=LatestSnapshotGeneratedAgeMs` : The interval in milliseconds since the latest snapshot that the node has generated. If no snapshot has been generated yet, this is the approximate time delta since the process was started. ### LatestSnapshotGeneratedBytes MBean: `kafka.server:type=SnapshotEmitter,name=LatestSnapshotGeneratedBytes` : The total size in bytes of the latest snapshot that the node has generated. If a snapshot has not been generated yet, this is the size of the latest snapshot that was loaded. If no snapshots have been generated or loaded, this is 0. ## Controller metrics The following metrics are exposed by a controller. For more about monitoring KRaft, see [Monitor KRaft](../kafka-metadata/config-kraft.md#monitor-kraft). ### ActiveBrokerCount MBean: `kafka.controller:type=KafkaController,name=ActiveBrokerCount` : The number of active brokers as observed by this controller. ### ActiveControllerCount MBean: `kafka.controller:type=KafkaController,name=ActiveControllerCount` : The number of active controllers in the cluster. Valid values are ‘0’ or ‘1’. Alert if the aggregated sum across all brokers in the cluster is anything other than 1 because there should be exactly one controller per cluster. ### EventQueueOperationsStartedCount MBean: `kafka.controller:type=KafkaController,name=EventQueueOperationsStartedCount` : For KRaft mode, the total number of controller event queue operations that were started. This includes deferred operations. ### EventQueueOperationsTimedOutCount MBean: `kafka.controller:type=KafkaController,name=EventQueueOperationsTimedOutCount` : For KRaft mode, the total number of controller event queue operations that timed out before they could be performed. ### EventQueueProcessingTimeMs MBean: `kafka.controller:type=ControllerEventManager,name=EventQueueProcessingTimeMs` : A Histogram of the time in milliseconds that requests spent being processed in the Controller Event Queue. ### EventQueueSize MBean: `kafka.controller:type=ControllerEventManager,name=EventQueueSize` : Size of the controller’s event queue. ### AvgIdleRatio MBean: `kafka.controller:type=ControllerEventManager,name=AvgIdleRatio` : The fraction of time the controller event manager thread spends idle, where 0.0 means the thread is always busy and 1.0 means the thread is always idle. ### EventQueueTimeMs MBean: `kafka.controller:type=ControllerEventManager,name=EventQueueTimeMs` : Time that an event (except the Idle event) waits, in milliseconds, in the controller event queue before being processed. ### FencedBrokerCount MBean: `kafka.controller:type=KafkaController,name=FencedBrokerCount` : In KRaft mode, the number of fenced, but registered brokers as observed by this controller. ### GlobalPartitionCount MBean: `kafka.controller:type=KafkaController,name=GlobalPartitionCount` : The number of partitions across all topics in the cluster. ### GlobalTopicCount MBean: `kafka.controller:type=KafkaController,name=GlobalTopicCount` : The number of global topics as observed by this Controller. ### LastAppliedRecordLagMs MBean: `kafka.controller:type=KafkaController,name=LastAppliedRecordLagMs` : The difference, in milliseconds, between now and the timestamp of the last record from the cluster metadata partition that was applied by the controller. For active controllers the value of this lag is always zero. ### LastAppliedRecordOffset MBean: `kafka.controller:type=KafkaController,name=LastAppliedRecordOffset` : The offset of the last record from the cluster metadata partition that was applied by the Controller. ### LastAppliedRecordTimestamp MBean: `kafka.controller:type=KafkaController,name=LastAppliedRecordTimestamp` : The timestamp of the last record from the cluster metadata partition that was applied by the controller. ### LastCommittedRecordOffset MBean: `kafka.controller:type=KafkaController,name=LastCommittedRecordOffset` : The offset of the last record committed to this Controller. ### MetadataErrorCount MBean: `kafka.controller:type=KafkaController,name=MetadataErrorCount` : The number of times this controller node has encountered an error during metadata log processing. ### NewActiveControllersCount MBean: `kafka.controller:type=KafkaController,name=NewActiveControllersCount` : For KRaft mode, counts the number of times this node has seen a new controller elected. A transition to the “no leader” state is not counted here. If the same controller as before becomes active, that still counts. ### OfflinePartitionsCount MBean: `kafka.controller:type=KafkaController,name=OfflinePartitionsCount,partition={partition}` : The number of partitions that don’t have an active leader and are therefore not writable or readable. Alert if value is greater than 0. ### PreferredReplicaImbalanceCount MBean: `kafka.controller:type=KafkaController,name=PreferredReplicaImbalanceCount` : The count of topic partitions for which the leader is not the preferred leader. ### ReplicasIneligibleToDeleteCount MBean: `kafka.controller:type=KafkaController,name=ReplicasIneligibleToDeleteCount` : The number of ineligible pending replica deletes. ### ReplicasToDeleteCount MBean: `kafka.controller:type=KafkaController,name=ReplicasToDeleteCount` : Pending replica deletes. ### TimedOutBrokerHeartbeatCount MBean: `kafka.controller:type=KafkaController,name=TimedOutBrokerHeartbeatCount` : For KRaft mode, the number of broker heartbeats that timed out on this controller since the process was started. Note that only active controllers handle heartbeats, so only they will see increases in this metric. ### TopicsIneligibleToDeleteCount MBean: `kafka.controller:type=KafkaController,name=TopicsIneligibleToDeleteCount` : Ineligible pending topic deletes. ### TopicsToDeleteCount MBean: `kafka.controller:type=KafkaController,name=TopicsToDeleteCount` : Pending topic deletes. ## Self-Balancing Clusters metrics Self-Balancing Clusters (Self-Balancing) exposes the following key metrics, which the broker controller that is running the active data balancer instance reports. You can see the full list of Self-Balancing metrics by running JConsole and navigating to the `kafka.databalancer` node. For more information on configuring JConsole, see [Configure JMX for Monitoring](configure-jmx.md#configure-jmx). For more on monitoring Self-Balancing, see [Metrics for monitoring a rebalance](../clusters/sbc/index.md#sbc-monitoring-metrics). ### ActiveBalancerCount MBean: `kafka.databalancer:type=KafkaDataBalanceManager,name=ActiveBalancerCount` : Indicates whether the Self-Balancing balancer is active on this broker: `1` when active, `0` when inactive, and `-1` when disabled by configuration. ### BalancerState MBean: `kafka.databalancer:type=ConfluentDataBalanceEngine,name=BalancerState,broker={brokerId}` : The current state of the Self-Balancing balancer on this broker. For example, `NOT_CONTROLLER`. ### BrokerRemovalOperationState MBean: `kafka.databalancer:type=ConfluentDataBalanceEngine,name=BrokerRemovalOperationState,broker={brokerId}` : The current state of a broker removal operation. For example, `NOT_STARTED`. ### replica-action-in-progress MBean: `kafka.databalancer:type=Executor,name=replica-action-in-progress` : The number of in-progress reassignment tasks currently tracked by Self-Balancing. ### replica-action-pending MBean: `kafka.databalancer:type=Executor,name=replica-action-pending` : The number of pending reassignment tasks currently tracked by Self-Balancing. ## Related content - [Monitor Kafka with JMX in Confluent Platform](monitoring.md#kafka-monitoring) - [Configure JMX for Monitoring](configure-jmx.md#configure-jmx) - [Log and Network Metrics](log-network-metrics.md#log-network-metrics) - [Group Coordinator Metrics](group-coordinator-metrics.md#group-coordinator-metrics) - [Producer Metrics](producer-metrics.md#producer-metrics) - [Consumer Metrics](consumer-metrics.md#consumer-metrics) - [Security Metrics](security-metrics.md#security-metrics) - Confluent Support: [The top 5 Broker JMX metrics you should be watching](https://support.confluent.io/hc/en-us/articles/360039629271) - Confluent Support: [Kafka Broker Performance Diagnostics](https://support.confluent.io/hc/en-us/articles/360001447266)