Kafka

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Integrations

Kafka (Exporter)

Learn how the Kafka (Exporter) integration connects with Netdata and how to configure it.

Kafka (go.d.plugin prometheus)

Learn how the Kafka (go.d.plugin prometheus) integration connects with Netdata and how to configure it.

Guides

Guides overview 1 page

Kafka Operations Guides

Practical guides for running, troubleshooting, and monitoring Apache Kafka in production.

Kafka Operations Guides 32 pages

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Kafka __consumer_offsets growing huge: compaction failure on the offsets topic

Diagnose and fix unbounded growth of Kafka's __consumer_offsets topic caused by a stalled or crashed log cleaner thread.

Kafka ActiveControllerCount not equal to 1: no controller or split brain

Diagnose and recover when the cluster-wide sum of Kafka ActiveControllerCount deviates from 1, indicating no active controller or split brain.

Kafka Broker May Not Be Available: How To Fix It

Diagnose why Kafka clients fail with 'Broker may not be available' even when the bootstrap server is reachable. Covers advertised.listeners misconfiguration, TLS and SASL handshake failures, firewall blocks, and genuine broker outages.

Kafka Broker Out Of Disk: How To Fix It

Diagnose and recover when a Kafka broker exhausts disk space on its log directories, including the cliff-edge shutdown behavior, uneven directory fill, and silent compaction failures.

Kafka CommitFailedException: rebalanced-out consumers and poll loop timeouts

Operational guide to diagnosing CommitFailedException caused by consumers evicted after exceeding max.poll.interval.ms during slow batch processing, and stopping rebalance storms.

Kafka consumer group lag growing: detection, lag-as-time, and root causes

Diagnose growing Kafka consumer group lag, convert offsets to time, and identify root causes from slow consumers to broker-side page cache and disk bottlenecks.

Kafka consumer group rebalancing too often: heartbeats, session timeout, and assignors

Diagnose and fix Kafka consumer groups that rebalance too frequently. Covers heartbeat timeouts, session expiry, max.poll.interval.ms, assignor behavior, and static membership.

Kafka consumer rebalance storm: stuck in PreparingRebalance and max.poll.interval.ms

Diagnose and fix Kafka consumer groups that oscillate between Stable and PreparingRebalance, driven by max.poll.interval.ms timeouts and client-side processing delays.

Kafka controller event queue backing up: overwhelmed controller and stalled metadata

Diagnose and recover when the Kafka controller's event queue backs up, stalling leader elections and metadata propagation.

Kafka disk I/O latency high: await, LocalTimeMs, and the slow-disk broker

Diagnose elevated disk I/O latency on Kafka brokers using iostat await and LocalTimeMs. Distinguish disk degradation from page cache misses and transient load.

Kafka FailedProduceRequestsPerSec rising: the single best 'producers are hurting' signal

Diagnose rising Kafka FailedProduceRequestsPerSec, correlate with ISR and replication health, and stop producer-visible failures before they cascade.

Kafka fetch request latency high: FetchConsumer vs FetchFollower and page cache misses

Diagnose elevated Kafka fetch request latency by distinguishing consumer fetches from replica fetches and identifying page cache misses as the root cause.

Kafka ISR shrinking: IsrShrinksPerSec, flapping, and the cascade to offline

Diagnose ISR shrink storms, flapping replicas, and the cascade to offline partitions in Kafka production clusters.

Kafka JVM heap and Full GC pauses: ISR drops, session timeouts, and right-sizing the heap

Diagnose and fix Kafka broker JVM heap pressure and Full GC pauses that trigger ISR shrinks, ZooKeeper session timeouts, and request latency spikes.

Kafka KRaft quorum has no leader: current-leader = -1 and frozen metadata

Diagnose and recover a KRaft quorum that has lost its leader when current-leader drops to -1 and metadata updates freeze.

Kafka LEADER_NOT_AVAILABLE: causes during elections, restarts, and topic creation

Diagnose transient and persistent Kafka LEADER_NOT_AVAILABLE errors by correlating leader elections, controller health, ISR state, and offline partitions.

Kafka log compaction falling behind: the dead cleaner thread and unbounded disk growth

Diagnose and fix silent Kafka log cleaner thread crashes that cause compacted topics like __consumer_offsets to grow without bound.

Kafka Log directory failed / OfflineLogDirectoryCount > 0: disk errors and JBOD recovery

Troubleshoot Kafka brokers with offline log directories due to disk I/O errors, JBOD failures, and recover partition availability without data loss.

Kafka min.insync.replicas and acks: configuring durability you actually have

Why acks=all without min.insync.replicas only guarantees leader durability, and how to configure Kafka replication for real fault tolerance without blocking writes.

Kafka monitoring checklist: the signals every production cluster needs

A production monitoring checklist for Apache Kafka organized by maturity level: survival, operational, mature, and expert signals every SRE should watch.

Kafka NetworkProcessorAvgIdlePercent low: network thread saturation and TLS overhead

Diagnose and fix low NetworkProcessorAvgIdlePercent in Kafka, including network thread saturation from TLS handshakes, connection storms, and large fetch responses.

Kafka NOT_LEADER_FOR_PARTITION: stale metadata, controller lag, and client retries

Diagnose persistent NOT_LEADER_FOR_PARTITION errors by distinguishing transient leader elections from controller event queue backup and broker metadata desync.

Kafka NotEnoughReplicasException: acks=all writes rejected below min.insync.replicas

Diagnose and fix Kafka NotEnoughReplicasException when acks=all writes fail because the ISR shrank below min.insync.replicas.

Kafka OfflinePartitionsCount > 0: partitions with no leader and how to recover

Diagnose and recover Kafka partitions with no active leader when OfflinePartitionsCount is nonzero.

Kafka OffsetOutOfRangeException: when retention deletes data before the consumer reads it

Fix and prevent Kafka OffsetOutOfRangeException when consumer lag outruns log retention, causing data loss or forced offset resets.

Kafka RecordTooLargeException / MESSAGE_TOO_LARGE: message size limits across the path

Fix Kafka message-size rejections by aligning producer, broker, topic, replica, and consumer limits end to end.

Kafka replica MaxLag growing: slow followers and replica fetcher health

Diagnose and fix growing Kafka replica fetcher lag before it triggers ISR shrinks and write rejections.

Kafka REQUEST_TIMED_OUT: produce requests that expire before replication completes

Diagnose and fix Kafka REQUEST_TIMED_OUT errors when acks=all produce requests expire waiting for replication, request queue backup, or slow disk.

Kafka Too many open files: file descriptor exhaustion from segments and connections

Diagnose and fix Kafka broker file descriptor exhaustion caused by log segments and network connections, including quick checks, fixes, and prevention.

Kafka UncleanLeaderElectionsPerSec > 0: confirmed silent data loss

What to do when Kafka's UncleanLeaderElectionsPerSec metric rises above zero, confirming silent data loss, and how to recover without deepening the damage.

Kafka UnderMinIsrPartitionCount: confirming the write path is blocked

How to read Kafka's UnderMinIsrPartitionCount metric, distinguish it from under-replication, and confirm producers are actively blocked.

Kafka UnderReplicatedPartitions > 0: the most important metric and how to clear it

Troubleshoot and clear Kafka under-replicated partitions by identifying lagging followers, correlating disk, network, and GC signals, and applying the right fix without causing further ISR shrink.

Apache ZooKeeper Operations Guides 1 page

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ZooKeeper KeeperErrorCode = NoNode: operating on a path that doesn't exist

Triage ZooKeeper NoNode errors: separate application bugs from session-expiration cascades with read-only checks and mntr signals.

Academy

Apache Kafka Consumer Lag: Troubleshooting & Fixes

A deep dive into the causes of consumer lag- how to monitor it- and how to tune your Kafka consumers for optimal performance

What Is Apache Kafka Used For Everything You Need To Know

Unpacking the power of Apache Kafka for modern data pipelines - from real-time analytics to robust messaging systems.

Kafka Consumer Lag Monitoring

Learn everything about monitoring & troubleshooting Kafka Consumer Lag, what metrics are important to monitor and why, and how to monitor Kafka Consumer Lag with Netdata.

Kafka Monitoring

Learn everything about monitoring & troubleshooting Kafka, what metrics are important to monitor and why, and how to monitor Kafka with Netdata.

Kafka ZooKeeper Monitoring

Learn everything about monitoring & troubleshooting Kafka ZooKeeper, what metrics are important to monitor and why, and how to monitor Kafka ZooKeeper with Netdata.

Resources

Best Kafka Monitoring Tools: 10 Ranked for 2026

We ranked 10 Kafka monitoring tools on consumer lag depth, collection resolution, alerting, and cost. See where Netdata, Prometheus, and Datadog land.