Kafka 4.2 → 4.3 Upgrade Guide

Kafka 4.3 brings 26 new configs, removes 0, and changes 0 defaults compared to 4.2.

+26 configs 25 KIPs

New Configurations

Config	Category	Default
controller.quorum.fetch.max.bytes	broker	1048576 (1 mebibyte)
controller.quorum.fetch.snapshot.max.bytes	broker	1048576 (1 mebibyte)
cordoned.log.dirs	broker
follower.fetch.last.tiered.offset.enable	broker	false
follower.replication.throttled.rate	broker	9223372036854775807
group.consumer.assignment.interval.ms	broker	1000 (1 second)
group.consumer.max.assignment.interval.ms	broker	15000 (15 seconds)
group.consumer.min.assignment.interval.ms	broker	0
group.coordinator.background.threads	broker	2
group.coordinator.cached.buffer.max.bytes	broker	1048588
group.share.assignment.interval.ms	broker	1000 (1 second)
group.share.max.assignment.interval.ms	broker	15000 (15 seconds)
group.share.max.delivery.count.limit	broker	10
group.share.max.partition.max.record.locks	broker	4000
group.share.min.assignment.interval.ms	broker	0
group.share.min.delivery.count.limit	broker	2
group.share.min.partition.max.record.locks	broker	100
group.streams.assignment.interval.ms	broker	1000 (1 second)
group.streams.max.assignment.interval.ms	broker	15000 (15 seconds)
group.streams.min.assignment.interval.ms	broker	0
leader.replication.throttled.rate	broker	9223372036854775807
replica.alter.log.dirs.io.max.bytes.per.second	broker	9223372036854775807
share.coordinator.cached.buffer.max.bytes	broker	1048588
dsl.store.format	stream	DEFAULT
processing.exception.handler.global.enabled	stream	false
state.cleanup.dir.max.age.ms	stream	-1

Protocol Changes

DescribeLogDirs v5 · DescribeLogDirs v5 · BrokerHeartbeat v2 · BrokerHeartbeat v2

KIPs Released

KIP-1035 StateStore managed changelog offsets
KIP-1066 Mechanism to cordon brokers and log directories
KIP-1196 Introduce group.coordinator.append.max.buffer.size config
KIP-1208 Add prefix to TopicBasedRemoteLogMetadataManagerConfig to enable setting admin configs
KIP-1211 Align the behavior of num.partitions and default.replication.factor for topic creation
KIP-1219 Configurations for KRaft Fetch and FetchSnapshot Byte Size
KIP-1235 Correct the default min.insync.replicas to 2 for the __remote_log_metadata topic
KIP-1237 Deprecate group.coordinator.rebalance.protocols config
KIP-1239 Batch offset translation in RemoteClusterUtils
KIP-1240 Additional group configurations for share groups
KIP-1244 Drop support for streams-scala in Kafka 5.0 (deprecate in 4.3)
KIP-1247 Make Bytes utils class part of the public API
KIP-1250 Add metric to track size of in-memory state stores
KIP-1251 Assignment epochs for consumer groups
KIP-1257 Partition Size Percentage Metrics for Storage Monitoring
KIP-1258 Add Support for OAuth Client Assertion to client_credentials Grant Type
KIP-1259 Add configuration to wipe Kafka Streams local state on startup
KIP-1263 Group Coordinator Assignment Batching and Offload
KIP-1264 Configurable TTL for Tiered Storage Index Cache
KIP-1270 Extend ProcessExceptionalHandler for GlobalThread
KIP-1271 Allow to Store Record Headers in State Stores
KIP-1273 Improve Connect configurable components discoverability
KIP-1274 Deprecate and remove support for Classic rebalance protocol in KafkaConsumer
KIP-1280 Update MirrorMaker to use KIP-877 to emit metrics
KIP-1285 DSL Opt-in Support for Headers-Aware State Stores