Appendix A. Broker configuration parameters
zookeeper.connect
Type: string
Importance: high
Dynamic update: read-only
Specifies the ZooKeeper connection string in the form
hostname:port
where host and port are the host and port of a ZooKeeper server. To allow connecting through other ZooKeeper nodes when that ZooKeeper machine is down you can also specify multiple hosts in the formhostname1:port1,hostname2:port2,hostname3:port3
. The server can also have a ZooKeeper chroot path as part of its ZooKeeper connection string which puts its data under some path in the global ZooKeeper namespace. For example to give a chroot path of/chroot/path
you would give the connection string ashostname1:port1,hostname2:port2,hostname3:port3/chroot/path
.advertised.host.name
Type: string
Default: null
Importance: high
Dynamic update: read-only
DEPRECATED: only used when
advertised.listeners
orlisteners
are not set. Useadvertised.listeners
instead. Hostname to publish to ZooKeeper for clients to use. In IaaS environments, this may need to be different from the interface to which the broker binds. If this is not set, it will use the value forhost.name
if configured. Otherwise it will use the value returned from java.net.InetAddress.getCanonicalHostName().advertised.listeners
Type: string
Default: null
Importance: high
Dynamic update: per-broker
Listeners to publish to ZooKeeper for clients to use, if different than the
listeners
config property. In IaaS environments, this may need to be different from the interface to which the broker binds. If this is not set, the value forlisteners
will be used. Unlikelisteners
it is not valid to advertise the 0.0.0.0 meta-address.advertised.port
Type: int
Default: null
Importance: high
Dynamic update: read-only
DEPRECATED: only used when
advertised.listeners
orlisteners
are not set. Useadvertised.listeners
instead. The port to publish to ZooKeeper for clients to use. In IaaS environments, this may need to be different from the port to which the broker binds. If this is not set, it will publish the same port that the broker binds to.auto.create.topics.enable
Type: boolean
Default: true
Importance: high
Dynamic update: read-only
Enable auto creation of topic on the server.
auto.leader.rebalance.enable
Type: boolean
Default: true
Importance: high
Dynamic update: read-only
Enables auto leader balancing. A background thread checks the distribution of partition leaders at regular intervals, configurable by
leader.imbalance.check.interval.seconds
. If the leader imbalance exceedsleader.imbalance.per.broker.percentage
, leader rebalance to the preferred leader for partitions is triggered.background.threads
Type: int
Default: 10
Valid Values: [1,…]
Importance: high
Dynamic update: cluster-wide
The number of threads to use for various background processing tasks.
broker.id
Type: int
Default: -1
Importance: high
Dynamic update: read-only
The broker id for this server. If unset, a unique broker id will be generated.To avoid conflicts between zookeeper generated broker id’s and user configured broker id’s, generated broker ids start from reserved.broker.max.id + 1.
compression.type
Type: string
Default: producer
Importance: high
Dynamic update: cluster-wide
Specify the final compression type for a given topic. This configuration accepts the standard compression codecs ('gzip', 'snappy', 'lz4', 'zstd'). It additionally accepts 'uncompressed' which is equivalent to no compression; and 'producer' which means retain the original compression codec set by the producer.
control.plane.listener.name
Type: string
Default: null
Importance: high
Dynamic update: read-only
Name of listener used for communication between controller and brokers. Broker will use the control.plane.listener.name to locate the endpoint in listeners list, to listen for connections from the controller. For example, if a broker’s config is : listeners = INTERNAL://192.1.1.8:9092, EXTERNAL://10.1.1.5:9093, CONTROLLER://192.1.1.8:9094 listener.security.protocol.map = INTERNAL:PLAINTEXT, EXTERNAL:SSL, CONTROLLER:SSL control.plane.listener.name = CONTROLLER On startup, the broker will start listening on "192.1.1.8:9094" with security protocol "SSL". On controller side, when it discovers a broker’s published endpoints through zookeeper, it will use the control.plane.listener.name to find the endpoint, which it will use to establish connection to the broker. For example, if the broker’s published endpoints on zookeeper are : "endpoints" : ["INTERNAL://broker1.example.com:9092","EXTERNAL://broker1.example.com:9093","CONTROLLER://broker1.example.com:9094"] and the controller’s config is : listener.security.protocol.map = INTERNAL:PLAINTEXT, EXTERNAL:SSL, CONTROLLER:SSL control.plane.listener.name = CONTROLLER then controller will use "broker1.example.com:9094" with security protocol "SSL" to connect to the broker. If not explicitly configured, the default value will be null and there will be no dedicated endpoints for controller connections.
delete.topic.enable
Type: boolean
Default: true
Importance: high
Dynamic update: read-only
Enables delete topic. Delete topic through the admin tool will have no effect if this config is turned off.
host.name
Type: string
Default: ""
Importance: high
Dynamic update: read-only
DEPRECATED: only used when
listeners
is not set. Uselisteners
instead. hostname of broker. If this is set, it will only bind to this address. If this is not set, it will bind to all interfaces.leader.imbalance.check.interval.seconds
Type: long
Default: 300
Importance: high
Dynamic update: read-only
The frequency with which the partition rebalance check is triggered by the controller.
leader.imbalance.per.broker.percentage
Type: int
Default: 10
Importance: high
Dynamic update: read-only
The ratio of leader imbalance allowed per broker. The controller would trigger a leader balance if it goes above this value per broker. The value is specified in percentage.
listeners
Type: string
Default: null
Importance: high
Dynamic update: per-broker
Listener List - Comma-separated list of URIs we will listen on and the listener names. If the listener name is not a security protocol, listener.security.protocol.map must also be set. Specify hostname as 0.0.0.0 to bind to all interfaces. Leave hostname empty to bind to default interface. Examples of legal listener lists: PLAINTEXT://myhost:9092,SSL://:9091 CLIENT://0.0.0.0:9092,REPLICATION://localhost:9093.
log.dir
Type: string
Default: /tmp/kafka-logs
Importance: high
Dynamic update: read-only
The directory in which the log data is kept (supplemental for log.dirs property).
log.dirs
Type: string
Default: null
Importance: high
Dynamic update: read-only
The directories in which the log data is kept. If not set, the value in log.dir is used.
log.flush.interval.messages
Type: long
Default: 9223372036854775807
Valid Values: [1,…]
Importance: high
Dynamic update: cluster-wide
The number of messages accumulated on a log partition before messages are flushed to disk.
log.flush.interval.ms
Type: long
Default: null
Importance: high
Dynamic update: cluster-wide
The maximum time in ms that a message in any topic is kept in memory before flushed to disk. If not set, the value in log.flush.scheduler.interval.ms is used.
log.flush.offset.checkpoint.interval.ms
Type: int
Default: 60000 (1 minute)
Valid Values: [0,…]
Importance: high
Dynamic update: read-only
The frequency with which we update the persistent record of the last flush which acts as the log recovery point.
log.flush.scheduler.interval.ms
Type: long
Default: 9223372036854775807
Importance: high
Dynamic update: read-only
The frequency in ms that the log flusher checks whether any log needs to be flushed to disk.
log.flush.start.offset.checkpoint.interval.ms
Type: int
Default: 60000 (1 minute)
Valid Values: [0,…]
Importance: high
Dynamic update: read-only
The frequency with which we update the persistent record of log start offset.
log.retention.bytes
Type: long
Default: -1
Importance: high
Dynamic update: cluster-wide
The maximum size of the log before deleting it.
log.retention.hours
Type: int
Default: 168
Importance: high
Dynamic update: read-only
The number of hours to keep a log file before deleting it (in hours), tertiary to log.retention.ms property.
log.retention.minutes
Type: int
Default: null
Importance: high
Dynamic update: read-only
The number of minutes to keep a log file before deleting it (in minutes), secondary to log.retention.ms property. If not set, the value in log.retention.hours is used.
log.retention.ms
Type: long
Default: null
Importance: high
Dynamic update: cluster-wide
The number of milliseconds to keep a log file before deleting it (in milliseconds), If not set, the value in log.retention.minutes is used. If set to -1, no time limit is applied.
log.roll.hours
Type: int
Default: 168
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The maximum time before a new log segment is rolled out (in hours), secondary to log.roll.ms property.
log.roll.jitter.hours
Type: int
Default: 0
Valid Values: [0,…]
Importance: high
Dynamic update: read-only
The maximum jitter to subtract from logRollTimeMillis (in hours), secondary to log.roll.jitter.ms property.
log.roll.jitter.ms
Type: long
Default: null
Importance: high
Dynamic update: cluster-wide
The maximum jitter to subtract from logRollTimeMillis (in milliseconds). If not set, the value in log.roll.jitter.hours is used.
log.roll.ms
Type: long
Default: null
Importance: high
Dynamic update: cluster-wide
The maximum time before a new log segment is rolled out (in milliseconds). If not set, the value in log.roll.hours is used.
log.segment.bytes
Type: int
Default: 1073741824 (1 gibibyte)
Valid Values: [14,…]
Importance: high
Dynamic update: cluster-wide
The maximum size of a single log file.
log.segment.delete.delay.ms
Type: long
Default: 60000 (1 minute)
Valid Values: [0,…]
Importance: high
Dynamic update: cluster-wide
The amount of time to wait before deleting a file from the filesystem.
message.max.bytes
Type: int
Default: 1048588
Valid Values: [0,…]
Importance: high
Dynamic update: cluster-wide
The largest record batch size allowed by Kafka (after compression if compression is enabled). If this is increased and there are consumers older than 0.10.2, the consumers' fetch size must also be increased so that they can fetch record batches this large. In the latest message format version, records are always grouped into batches for efficiency. In previous message format versions, uncompressed records are not grouped into batches and this limit only applies to a single record in that case.This can be set per topic with the topic level
max.message.bytes
config.min.insync.replicas
Type: int
Default: 1
Valid Values: [1,…]
Importance: high
Dynamic update: cluster-wide
When a producer sets acks to "all" (or "-1"), min.insync.replicas specifies the minimum number of replicas that must acknowledge a write for the write to be considered successful. If this minimum cannot be met, then the producer will raise an exception (either NotEnoughReplicas or NotEnoughReplicasAfterAppend). When used together, min.insync.replicas and acks allow you to enforce greater durability guarantees. A typical scenario would be to create a topic with a replication factor of 3, set min.insync.replicas to 2, and produce with acks of "all". This will ensure that the producer raises an exception if a majority of replicas do not receive a write.
num.io.threads
Type: int
Default: 8
Valid Values: [1,…]
Importance: high
Dynamic update: cluster-wide
The number of threads that the server uses for processing requests, which may include disk I/O.
num.network.threads
Type: int
Default: 3
Valid Values: [1,…]
Importance: high
Dynamic update: cluster-wide
The number of threads that the server uses for receiving requests from the network and sending responses to the network.
num.recovery.threads.per.data.dir
Type: int
Default: 1
Valid Values: [1,…]
Importance: high
Dynamic update: cluster-wide
The number of threads per data directory to be used for log recovery at startup and flushing at shutdown.
num.replica.alter.log.dirs.threads
Type: int
Default: null
Importance: high
Dynamic update: read-only
The number of threads that can move replicas between log directories, which may include disk I/O.
num.replica.fetchers
Type: int
Default: 1
Importance: high
Dynamic update: cluster-wide
Number of fetcher threads used to replicate messages from a source broker. Increasing this value can increase the degree of I/O parallelism in the follower broker.
offset.metadata.max.bytes
Type: int
Default: 4096 (4 kibibytes)
Importance: high
Dynamic update: read-only
The maximum size for a metadata entry associated with an offset commit.
offsets.commit.required.acks
Type: short
Default: -1
Importance: high
Dynamic update: read-only
The required acks before the commit can be accepted. In general, the default (-1) should not be overridden.
offsets.commit.timeout.ms
Type: int
Default: 5000 (5 seconds)
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
Offset commit will be delayed until all replicas for the offsets topic receive the commit or this timeout is reached. This is similar to the producer request timeout.
offsets.load.buffer.size
Type: int
Default: 5242880
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
Batch size for reading from the offsets segments when loading offsets into the cache (soft-limit, overridden if records are too large).
offsets.retention.check.interval.ms
Type: long
Default: 600000 (10 minutes)
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
Frequency at which to check for stale offsets.
offsets.retention.minutes
Type: int
Default: 10080
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
After a consumer group loses all its consumers (i.e. becomes empty) its offsets will be kept for this retention period before getting discarded. For standalone consumers (using manual assignment), offsets will be expired after the time of last commit plus this retention period.
offsets.topic.compression.codec
Type: int
Default: 0
Importance: high
Dynamic update: read-only
Compression codec for the offsets topic - compression may be used to achieve "atomic" commits.
offsets.topic.num.partitions
Type: int
Default: 50
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The number of partitions for the offset commit topic (should not change after deployment).
offsets.topic.replication.factor
Type: short
Default: 3
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The replication factor for the offsets topic (set higher to ensure availability). Internal topic creation will fail until the cluster size meets this replication factor requirement.
offsets.topic.segment.bytes
Type: int
Default: 104857600 (100 mebibytes)
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The offsets topic segment bytes should be kept relatively small in order to facilitate faster log compaction and cache loads.
port
Type: int
Default: 9092
Importance: high
Dynamic update: read-only
DEPRECATED: only used when
listeners
is not set. Uselisteners
instead. the port to listen and accept connections on.queued.max.requests
Type: int
Default: 500
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The number of queued requests allowed for data-plane, before blocking the network threads.
quota.consumer.default
Type: long
Default: 9223372036854775807
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
DEPRECATED: Used only when dynamic default quotas are not configured for <user, <client-id> or <user, client-id> in Zookeeper. Any consumer distinguished by clientId/consumer group will get throttled if it fetches more bytes than this value per-second.
quota.producer.default
Type: long
Default: 9223372036854775807
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
DEPRECATED: Used only when dynamic default quotas are not configured for <user>, <client-id> or <user, client-id> in Zookeeper. Any producer distinguished by clientId will get throttled if it produces more bytes than this value per-second.
replica.fetch.min.bytes
Type: int
Default: 1
Importance: high
Dynamic update: read-only
Minimum bytes expected for each fetch response. If not enough bytes, wait up to replicaMaxWaitTimeMs.
replica.fetch.wait.max.ms
Type: int
Default: 500
Importance: high
Dynamic update: read-only
max wait time for each fetcher request issued by follower replicas. This value should always be less than the replica.lag.time.max.ms at all times to prevent frequent shrinking of ISR for low throughput topics.
replica.high.watermark.checkpoint.interval.ms
Type: long
Default: 5000 (5 seconds)
Importance: high
Dynamic update: read-only
The frequency with which the high watermark is saved out to disk.
replica.lag.time.max.ms
Type: long
Default: 30000 (30 seconds)
Importance: high
Dynamic update: read-only
If a follower hasn’t sent any fetch requests or hasn’t consumed up to the leaders log end offset for at least this time, the leader will remove the follower from isr.
replica.socket.receive.buffer.bytes
Type: int
Default: 65536 (64 kibibytes)
Importance: high
Dynamic update: read-only
The socket receive buffer for network requests.
replica.socket.timeout.ms
Type: int
Default: 30000 (30 seconds)
Importance: high
Dynamic update: read-only
The socket timeout for network requests. Its value should be at least replica.fetch.wait.max.ms.
request.timeout.ms
Type: int
Default: 30000 (30 seconds)
Importance: high
Dynamic update: read-only
The configuration controls the maximum amount of time the client will wait for the response of a request. If the response is not received before the timeout elapses the client will resend the request if necessary or fail the request if retries are exhausted.
socket.receive.buffer.bytes
Type: int
Default: 102400 (100 kibibytes)
Importance: high
Dynamic update: read-only
The SO_RCVBUF buffer of the socket server sockets. If the value is -1, the OS default will be used.
socket.request.max.bytes
Type: int
Default: 104857600 (100 mebibytes)
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The maximum number of bytes in a socket request.
socket.send.buffer.bytes
Type: int
Default: 102400 (100 kibibytes)
Importance: high
Dynamic update: read-only
The SO_SNDBUF buffer of the socket server sockets. If the value is -1, the OS default will be used.
transaction.max.timeout.ms
Type: int
Default: 900000 (15 minutes)
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The maximum allowed timeout for transactions. If a client’s requested transaction time exceed this, then the broker will return an error in InitProducerIdRequest. This prevents a client from too large of a timeout, which can stall consumers reading from topics included in the transaction.
transaction.state.log.load.buffer.size
Type: int
Default: 5242880
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
Batch size for reading from the transaction log segments when loading producer ids and transactions into the cache (soft-limit, overridden if records are too large).
transaction.state.log.min.isr
Type: int
Default: 2
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
Overridden min.insync.replicas config for the transaction topic.
transaction.state.log.num.partitions
Type: int
Default: 50
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The number of partitions for the transaction topic (should not change after deployment).
transaction.state.log.replication.factor
Type: short
Default: 3
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The replication factor for the transaction topic (set higher to ensure availability). Internal topic creation will fail until the cluster size meets this replication factor requirement.
transaction.state.log.segment.bytes
Type: int
Default: 104857600 (100 mebibytes)
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The transaction topic segment bytes should be kept relatively small in order to facilitate faster log compaction and cache loads.
transactional.id.expiration.ms
Type: int
Default: 604800000 (7 days)
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The time in ms that the transaction coordinator will wait without receiving any transaction status updates for the current transaction before expiring its transactional id. This setting also influences producer id expiration - producer ids are expired once this time has elapsed after the last write with the given producer id. Note that producer ids may expire sooner if the last write from the producer id is deleted due to the topic’s retention settings.
unclean.leader.election.enable
Type: boolean
Default: false
Importance: high
Dynamic update: cluster-wide
Indicates whether to enable replicas not in the ISR set to be elected as leader as a last resort, even though doing so may result in data loss.
zookeeper.connection.timeout.ms
Type: int
Default: null
Importance: high
Dynamic update: read-only
The max time that the client waits to establish a connection to zookeeper. If not set, the value in zookeeper.session.timeout.ms is used.
zookeeper.max.in.flight.requests
Type: int
Default: 10
Valid Values: [1,…]
Importance: high
Dynamic update: read-only
The maximum number of unacknowledged requests the client will send to Zookeeper before blocking.
zookeeper.session.timeout.ms
Type: int
Default: 18000 (18 seconds)
Importance: high
Dynamic update: read-only
Zookeeper session timeout.
zookeeper.set.acl
Type: boolean
Default: false
Importance: high
Dynamic update: read-only
Set client to use secure ACLs.
broker.id.generation.enable
Type: boolean
Default: true
Importance: medium
Dynamic update: read-only
Enable automatic broker id generation on the server. When enabled the value configured for reserved.broker.max.id should be reviewed.
broker.rack
Type: string
Default: null
Importance: medium
Dynamic update: read-only
Rack of the broker. This will be used in rack aware replication assignment for fault tolerance. Examples:
RACK1
,us-east-1d
.connections.max.idle.ms
Type: long
Default: 600000 (10 minutes)
Importance: medium
Dynamic update: read-only
Idle connections timeout: the server socket processor threads close the connections that idle more than this.
connections.max.reauth.ms
Type: long
Default: 0
Importance: medium
Dynamic update: read-only
When explicitly set to a positive number (the default is 0, not a positive number), a session lifetime that will not exceed the configured value will be communicated to v2.2.0 or later clients when they authenticate. The broker will disconnect any such connection that is not re-authenticated within the session lifetime and that is then subsequently used for any purpose other than re-authentication. Configuration names can optionally be prefixed with listener prefix and SASL mechanism name in lower-case. For example, listener.name.sasl_ssl.oauthbearer.connections.max.reauth.ms=3600000.
controlled.shutdown.enable
Type: boolean
Default: true
Importance: medium
Dynamic update: read-only
Enable controlled shutdown of the server.
controlled.shutdown.max.retries
Type: int
Default: 3
Importance: medium
Dynamic update: read-only
Controlled shutdown can fail for multiple reasons. This determines the number of retries when such failure happens.
controlled.shutdown.retry.backoff.ms
Type: long
Default: 5000 (5 seconds)
Importance: medium
Dynamic update: read-only
Before each retry, the system needs time to recover from the state that caused the previous failure (Controller fail over, replica lag etc). This config determines the amount of time to wait before retrying.
controller.socket.timeout.ms
Type: int
Default: 30000 (30 seconds)
Importance: medium
Dynamic update: read-only
The socket timeout for controller-to-broker channels.
default.replication.factor
Type: int
Default: 1
Importance: medium
Dynamic update: read-only
default replication factors for automatically created topics.
delegation.token.expiry.time.ms
Type: long
Default: 86400000 (1 day)
Valid Values: [1,…]
Importance: medium
Dynamic update: read-only
The token validity time in miliseconds before the token needs to be renewed. Default value 1 day.
delegation.token.master.key
Type: password
Default: null
Importance: medium
Dynamic update: read-only
Master/secret key to generate and verify delegation tokens. Same key must be configured across all the brokers. If the key is not set or set to empty string, brokers will disable the delegation token support.
delegation.token.max.lifetime.ms
Type: long
Default: 604800000 (7 days)
Valid Values: [1,…]
Importance: medium
Dynamic update: read-only
The token has a maximum lifetime beyond which it cannot be renewed anymore. Default value 7 days.
delete.records.purgatory.purge.interval.requests
Type: int
Default: 1
Importance: medium
Dynamic update: read-only
The purge interval (in number of requests) of the delete records request purgatory.
fetch.max.bytes
Type: int
Default: 57671680 (55 mebibytes)
Valid Values: [1024,…]
Importance: medium
Dynamic update: read-only
The maximum number of bytes we will return for a fetch request. Must be at least 1024.
fetch.purgatory.purge.interval.requests
Type: int
Default: 1000
Importance: medium
Dynamic update: read-only
The purge interval (in number of requests) of the fetch request purgatory.
group.initial.rebalance.delay.ms
Type: int
Default: 3000 (3 seconds)
Importance: medium
Dynamic update: read-only
The amount of time the group coordinator will wait for more consumers to join a new group before performing the first rebalance. A longer delay means potentially fewer rebalances, but increases the time until processing begins.
group.max.session.timeout.ms
Type: int
Default: 1800000 (30 minutes)
Importance: medium
Dynamic update: read-only
The maximum allowed session timeout for registered consumers. Longer timeouts give consumers more time to process messages in between heartbeats at the cost of a longer time to detect failures.
group.max.size
Type: int
Default: 2147483647
Valid Values: [1,…]
Importance: medium
Dynamic update: read-only
The maximum number of consumers that a single consumer group can accommodate.
group.min.session.timeout.ms
Type: int
Default: 6000 (6 seconds)
Importance: medium
Dynamic update: read-only
The minimum allowed session timeout for registered consumers. Shorter timeouts result in quicker failure detection at the cost of more frequent consumer heartbeating, which can overwhelm broker resources.
inter.broker.listener.name
Type: string
Default: null
Importance: medium
Dynamic update: read-only
Name of listener used for communication between brokers. If this is unset, the listener name is defined by security.inter.broker.protocol. It is an error to set this and security.inter.broker.protocol properties at the same time.
inter.broker.protocol.version
Type: string
Default: 2.6-IV0
Valid Values: [0.8.0, 0.8.1, 0.8.2, 0.9.0, 0.10.0-IV0, 0.10.0-IV1, 0.10.1-IV0, 0.10.1-IV1, 0.10.1-IV2, 0.10.2-IV0, 0.11.0-IV0, 0.11.0-IV1, 0.11.0-IV2, 1.0-IV0, 1.1-IV0, 2.0-IV0, 2.0-IV1, 2.1-IV0, 2.1-IV1, 2.1-IV2, 2.2-IV0, 2.2-IV1, 2.3-IV0, 2.3-IV1, 2.4-IV0, 2.4-IV1, 2.5-IV0, 2.6-IV0]
Importance: medium
Dynamic update: read-only
Specify which version of the inter-broker protocol will be used. This is typically bumped after all brokers were upgraded to a new version. Example of some valid values are: 0.8.0, 0.8.1, 0.8.1.1, 0.8.2, 0.8.2.0, 0.8.2.1, 0.9.0.0, 0.9.0.1 Check ApiVersion for the full list.
log.cleaner.backoff.ms
Type: long
Default: 15000 (15 seconds)
Valid Values: [0,…]
Importance: medium
Dynamic update: cluster-wide
The amount of time to sleep when there are no logs to clean.
log.cleaner.dedupe.buffer.size
Type: long
Default: 134217728
Importance: medium
Dynamic update: cluster-wide
The total memory used for log deduplication across all cleaner threads.
log.cleaner.delete.retention.ms
Type: long
Default: 86400000 (1 day)
Importance: medium
Dynamic update: cluster-wide
How long are delete records retained?
log.cleaner.enable
Type: boolean
Default: true
Importance: medium
Dynamic update: read-only
Enable the log cleaner process to run on the server. Should be enabled if using any topics with a cleanup.policy=compact including the internal offsets topic. If disabled those topics will not be compacted and continually grow in size.
log.cleaner.io.buffer.load.factor
Type: double
Default: 0.9
Importance: medium
Dynamic update: cluster-wide
Log cleaner dedupe buffer load factor. The percentage full the dedupe buffer can become. A higher value will allow more log to be cleaned at once but will lead to more hash collisions.
log.cleaner.io.buffer.size
Type: int
Default: 524288
Valid Values: [0,…]
Importance: medium
Dynamic update: cluster-wide
The total memory used for log cleaner I/O buffers across all cleaner threads.
log.cleaner.io.max.bytes.per.second
Type: double
Default: 1.7976931348623157E308
Importance: medium
Dynamic update: cluster-wide
The log cleaner will be throttled so that the sum of its read and write i/o will be less than this value on average.
log.cleaner.max.compaction.lag.ms
Type: long
Default: 9223372036854775807
Importance: medium
Dynamic update: cluster-wide
The maximum time a message will remain ineligible for compaction in the log. Only applicable for logs that are being compacted.
log.cleaner.min.cleanable.ratio
Type: double
Default: 0.5
Importance: medium
Dynamic update: cluster-wide
The minimum ratio of dirty log to total log for a log to eligible for cleaning. If the log.cleaner.max.compaction.lag.ms or the log.cleaner.min.compaction.lag.ms configurations are also specified, then the log compactor considers the log eligible for compaction as soon as either: (i) the dirty ratio threshold has been met and the log has had dirty (uncompacted) records for at least the log.cleaner.min.compaction.lag.ms duration, or (ii) if the log has had dirty (uncompacted) records for at most the log.cleaner.max.compaction.lag.ms period.
log.cleaner.min.compaction.lag.ms
Type: long
Default: 0
Importance: medium
Dynamic update: cluster-wide
The minimum time a message will remain uncompacted in the log. Only applicable for logs that are being compacted.
log.cleaner.threads
Type: int
Default: 1
Valid Values: [0,…]
Importance: medium
Dynamic update: cluster-wide
The number of background threads to use for log cleaning.
log.cleanup.policy
Type: list
Default: delete
Valid Values: [compact, delete]
Importance: medium
Dynamic update: cluster-wide
The default cleanup policy for segments beyond the retention window. A comma separated list of valid policies. Valid policies are: "delete" and "compact".
log.index.interval.bytes
Type: int
Default: 4096 (4 kibibytes)
Valid Values: [0,…]
Importance: medium
Dynamic update: cluster-wide
The interval with which we add an entry to the offset index.
log.index.size.max.bytes
Type: int
Default: 10485760 (10 mebibytes)
Valid Values: [4,…]
Importance: medium
Dynamic update: cluster-wide
The maximum size in bytes of the offset index.
log.message.format.version
Type: string
Default: 2.6-IV0
Valid Values: [0.8.0, 0.8.1, 0.8.2, 0.9.0, 0.10.0-IV0, 0.10.0-IV1, 0.10.1-IV0, 0.10.1-IV1, 0.10.1-IV2, 0.10.2-IV0, 0.11.0-IV0, 0.11.0-IV1, 0.11.0-IV2, 1.0-IV0, 1.1-IV0, 2.0-IV0, 2.0-IV1, 2.1-IV0, 2.1-IV1, 2.1-IV2, 2.2-IV0, 2.2-IV1, 2.3-IV0, 2.3-IV1, 2.4-IV0, 2.4-IV1, 2.5-IV0, 2.6-IV0]
Importance: medium
Dynamic update: read-only
Specify the message format version the broker will use to append messages to the logs. The value should be a valid ApiVersion. Some examples are: 0.8.2, 0.9.0.0, 0.10.0, check ApiVersion for more details. By setting a particular message format version, the user is certifying that all the existing messages on disk are smaller or equal than the specified version. Setting this value incorrectly will cause consumers with older versions to break as they will receive messages with a format that they don’t understand.
log.message.timestamp.difference.max.ms
Type: long
Default: 9223372036854775807
Importance: medium
Dynamic update: cluster-wide
The maximum difference allowed between the timestamp when a broker receives a message and the timestamp specified in the message. If log.message.timestamp.type=CreateTime, a message will be rejected if the difference in timestamp exceeds this threshold. This configuration is ignored if log.message.timestamp.type=LogAppendTime.The maximum timestamp difference allowed should be no greater than log.retention.ms to avoid unnecessarily frequent log rolling.
log.message.timestamp.type
Type: string
Default: CreateTime
Valid Values: [CreateTime, LogAppendTime]
Importance: medium
Dynamic update: cluster-wide
Define whether the timestamp in the message is message create time or log append time. The value should be either
CreateTime
orLogAppendTime
.log.preallocate
Type: boolean
Default: false
Importance: medium
Dynamic update: cluster-wide
Should pre allocate file when create new segment? If you are using Kafka on Windows, you probably need to set it to true.
log.retention.check.interval.ms
Type: long
Default: 300000 (5 minutes)
Valid Values: [1,…]
Importance: medium
Dynamic update: read-only
The frequency in milliseconds that the log cleaner checks whether any log is eligible for deletion.
max.connections
Type: int
Default: 2147483647
Valid Values: [0,…]
Importance: medium
Dynamic update: cluster-wide
The maximum number of connections we allow in the broker at any time. This limit is applied in addition to any per-ip limits configured using max.connections.per.ip. Listener-level limits may also be configured by prefixing the config name with the listener prefix, for example,
listener.name.internal.max.connections
. Broker-wide limit should be configured based on broker capacity while listener limits should be configured based on application requirements. New connections are blocked if either the listener or broker limit is reached. Connections on the inter-broker listener are permitted even if broker-wide limit is reached. The least recently used connection on another listener will be closed in this case.max.connections.per.ip
Type: int
Default: 2147483647
Valid Values: [0,…]
Importance: medium
Dynamic update: cluster-wide
The maximum number of connections we allow from each ip address. This can be set to 0 if there are overrides configured using max.connections.per.ip.overrides property. New connections from the ip address are dropped if the limit is reached.
max.connections.per.ip.overrides
Type: string
Default: ""
Importance: medium
Dynamic update: cluster-wide
A comma-separated list of per-ip or hostname overrides to the default maximum number of connections. An example value is "hostName:100,127.0.0.1:200".
max.incremental.fetch.session.cache.slots
Type: int
Default: 1000
Valid Values: [0,…]
Importance: medium
Dynamic update: read-only
The maximum number of incremental fetch sessions that we will maintain.
num.partitions
Type: int
Default: 1
Valid Values: [1,…]
Importance: medium
Dynamic update: read-only
The default number of log partitions per topic.
password.encoder.old.secret
Type: password
Default: null
Importance: medium
Dynamic update: read-only
The old secret that was used for encoding dynamically configured passwords. This is required only when the secret is updated. If specified, all dynamically encoded passwords are decoded using this old secret and re-encoded using password.encoder.secret when broker starts up.
password.encoder.secret
Type: password
Default: null
Importance: medium
Dynamic update: read-only
The secret used for encoding dynamically configured passwords for this broker.
principal.builder.class
Type: class
Default: null
Importance: medium
Dynamic update: per-broker
The fully qualified name of a class that implements the KafkaPrincipalBuilder interface, which is used to build the KafkaPrincipal object used during authorization. This config also supports the deprecated PrincipalBuilder interface which was previously used for client authentication over SSL. If no principal builder is defined, the default behavior depends on the security protocol in use. For SSL authentication, the principal will be derived using the rules defined by
ssl.principal.mapping.rules
applied on the distinguished name from the client certificate if one is provided; otherwise, if client authentication is not required, the principal name will be ANONYMOUS. For SASL authentication, the principal will be derived using the rules defined bysasl.kerberos.principal.to.local.rules
if GSSAPI is in use, and the SASL authentication ID for other mechanisms. For PLAINTEXT, the principal will be ANONYMOUS.producer.purgatory.purge.interval.requests
Type: int
Default: 1000
Importance: medium
Dynamic update: read-only
The purge interval (in number of requests) of the producer request purgatory.
queued.max.request.bytes
Type: long
Default: -1
Importance: medium
Dynamic update: read-only
The number of queued bytes allowed before no more requests are read.
replica.fetch.backoff.ms
Type: int
Default: 1000 (1 second)
Valid Values: [0,…]
Importance: medium
Dynamic update: read-only
The amount of time to sleep when fetch partition error occurs.
replica.fetch.max.bytes
Type: int
Default: 1048576 (1 mebibyte)
Valid Values: [0,…]
Importance: medium
Dynamic update: read-only
The number of bytes of messages to attempt to fetch for each partition. This is not an absolute maximum, if the first record batch in the first non-empty partition of the fetch is larger than this value, the record batch will still be returned to ensure that progress can be made. The maximum record batch size accepted by the broker is defined via
message.max.bytes
(broker config) ormax.message.bytes
(topic config).replica.fetch.response.max.bytes
Type: int
Default: 10485760 (10 mebibytes)
Valid Values: [0,…]
Importance: medium
Dynamic update: read-only
Maximum bytes expected for the entire fetch response. Records are fetched in batches, and if the first record batch in the first non-empty partition of the fetch is larger than this value, the record batch will still be returned to ensure that progress can be made. As such, this is not an absolute maximum. The maximum record batch size accepted by the broker is defined via
message.max.bytes
(broker config) ormax.message.bytes
(topic config).replica.selector.class
Type: string
Default: null
Importance: medium
Dynamic update: read-only
The fully qualified class name that implements ReplicaSelector. This is used by the broker to find the preferred read replica. By default, we use an implementation that returns the leader.
reserved.broker.max.id
Type: int
Default: 1000
Valid Values: [0,…]
Importance: medium
Dynamic update: read-only
Max number that can be used for a broker.id.
sasl.client.callback.handler.class
Type: class
Default: null
Importance: medium
Dynamic update: read-only
The fully qualified name of a SASL client callback handler class that implements the AuthenticateCallbackHandler interface.
sasl.enabled.mechanisms
Type: list
Default: GSSAPI
Importance: medium
Dynamic update: per-broker
The list of SASL mechanisms enabled in the Kafka server. The list may contain any mechanism for which a security provider is available. Only GSSAPI is enabled by default.
sasl.jaas.config
Type: password
Default: null
Importance: medium
Dynamic update: per-broker
JAAS login context parameters for SASL connections in the format used by JAAS configuration files. JAAS configuration file format is described here. The format for the value is: ‘loginModuleClass controlFlag (optionName=optionValue)*;’. For brokers, the config must be prefixed with listener prefix and SASL mechanism name in lower-case. For example, listener.name.sasl_ssl.scram-sha-256.sasl.jaas.config=com.example.ScramLoginModule required;.
sasl.kerberos.kinit.cmd
Type: string
Default: /usr/bin/kinit
Importance: medium
Dynamic update: per-broker
Kerberos kinit command path.
sasl.kerberos.min.time.before.relogin
Type: long
Default: 60000
Importance: medium
Dynamic update: per-broker
Login thread sleep time between refresh attempts.
sasl.kerberos.principal.to.local.rules
Type: list
Default: DEFAULT
Importance: medium
Dynamic update: per-broker
A list of rules for mapping from principal names to short names (typically operating system usernames). The rules are evaluated in order and the first rule that matches a principal name is used to map it to a short name. Any later rules in the list are ignored. By default, principal names of the form {username}/{hostname}@{REALM} are mapped to {username}. For more details on the format please see security authorization and acls. Note that this configuration is ignored if an extension of KafkaPrincipalBuilder is provided by the
principal.builder.class
configuration.sasl.kerberos.service.name
Type: string
Default: null
Importance: medium
Dynamic update: per-broker
The Kerberos principal name that Kafka runs as. This can be defined either in Kafka’s JAAS config or in Kafka’s config.
sasl.kerberos.ticket.renew.jitter
Type: double
Default: 0.05
Importance: medium
Dynamic update: per-broker
Percentage of random jitter added to the renewal time.
sasl.kerberos.ticket.renew.window.factor
Type: double
Default: 0.8
Importance: medium
Dynamic update: per-broker
Login thread will sleep until the specified window factor of time from last refresh to ticket’s expiry has been reached, at which time it will try to renew the ticket.
sasl.login.callback.handler.class
Type: class
Default: null
Importance: medium
Dynamic update: read-only
The fully qualified name of a SASL login callback handler class that implements the AuthenticateCallbackHandler interface. For brokers, login callback handler config must be prefixed with listener prefix and SASL mechanism name in lower-case. For example, listener.name.sasl_ssl.scram-sha-256.sasl.login.callback.handler.class=com.example.CustomScramLoginCallbackHandler.
sasl.login.class
Type: class
Default: null
Importance: medium
Dynamic update: read-only
The fully qualified name of a class that implements the Login interface. For brokers, login config must be prefixed with listener prefix and SASL mechanism name in lower-case. For example, listener.name.sasl_ssl.scram-sha-256.sasl.login.class=com.example.CustomScramLogin.
sasl.login.refresh.buffer.seconds
Type: short
Default: 300
Importance: medium
Dynamic update: per-broker
The amount of buffer time before credential expiration to maintain when refreshing a credential, in seconds. If a refresh would otherwise occur closer to expiration than the number of buffer seconds then the refresh will be moved up to maintain as much of the buffer time as possible. Legal values are between 0 and 3600 (1 hour); a default value of 300 (5 minutes) is used if no value is specified. This value and sasl.login.refresh.min.period.seconds are both ignored if their sum exceeds the remaining lifetime of a credential. Currently applies only to OAUTHBEARER.
sasl.login.refresh.min.period.seconds
Type: short
Default: 60
Importance: medium
Dynamic update: per-broker
The desired minimum time for the login refresh thread to wait before refreshing a credential, in seconds. Legal values are between 0 and 900 (15 minutes); a default value of 60 (1 minute) is used if no value is specified. This value and sasl.login.refresh.buffer.seconds are both ignored if their sum exceeds the remaining lifetime of a credential. Currently applies only to OAUTHBEARER.
sasl.login.refresh.window.factor
Type: double
Default: 0.8
Importance: medium
Dynamic update: per-broker
Login refresh thread will sleep until the specified window factor relative to the credential’s lifetime has been reached, at which time it will try to refresh the credential. Legal values are between 0.5 (50%) and 1.0 (100%) inclusive; a default value of 0.8 (80%) is used if no value is specified. Currently applies only to OAUTHBEARER.
sasl.login.refresh.window.jitter
Type: double
Default: 0.05
Importance: medium
Dynamic update: per-broker
The maximum amount of random jitter relative to the credential’s lifetime that is added to the login refresh thread’s sleep time. Legal values are between 0 and 0.25 (25%) inclusive; a default value of 0.05 (5%) is used if no value is specified. Currently applies only to OAUTHBEARER.
sasl.mechanism.inter.broker.protocol
Type: string
Default: GSSAPI
Importance: medium
Dynamic update: per-broker
SASL mechanism used for inter-broker communication. Default is GSSAPI.
sasl.server.callback.handler.class
Type: class
Default: null
Importance: medium
Dynamic update: read-only
The fully qualified name of a SASL server callback handler class that implements the AuthenticateCallbackHandler interface. Server callback handlers must be prefixed with listener prefix and SASL mechanism name in lower-case. For example, listener.name.sasl_ssl.plain.sasl.server.callback.handler.class=com.example.CustomPlainCallbackHandler.
security.inter.broker.protocol
Type: string
Default: PLAINTEXT
Importance: medium
Dynamic update: read-only
Security protocol used to communicate between brokers. Valid values are: PLAINTEXT, SSL, SASL_PLAINTEXT, SASL_SSL. It is an error to set this and inter.broker.listener.name properties at the same time.
ssl.cipher.suites
Type: list
Default: ""
Importance: medium
Dynamic update: per-broker
A list of cipher suites. This is a named combination of authentication, encryption, MAC and key exchange algorithm used to negotiate the security settings for a network connection using TLS or SSL network protocol. By default all the available cipher suites are supported.
ssl.client.auth
Type: string
Default: none
Valid Values: [required, requested, none]
Importance: medium
Dynamic update: per-broker
Configures kafka broker to request client authentication. The following settings are common:
-
ssl.client.auth=required
If set to required client authentication is required. -
ssl.client.auth=requested
This means client authentication is optional. unlike requested , if this option is set client can choose not to provide authentication information about itself -
ssl.client.auth=none
This means client authentication is not needed.
-
ssl.enabled.protocols
Type: list
Default: TLSv1.2,TLSv1.3
Importance: medium
Dynamic update: per-broker
The list of protocols enabled for SSL connections. The default is 'TLSv1.2,TLSv1.3' when running with Java 11 or newer, 'TLSv1.2' otherwise. With the default value for Java 11, clients and servers will prefer TLSv1.3 if both support it and fallback to TLSv1.2 otherwise (assuming both support at least TLSv1.2). This default should be fine for most cases. Also see the config documentation for
ssl.protocol
.ssl.key.password
Type: password
Default: null
Importance: medium
Dynamic update: per-broker
The password of the private key in the key store file. This is optional for client.
ssl.keymanager.algorithm
Type: string
Default: SunX509
Importance: medium
Dynamic update: per-broker
The algorithm used by key manager factory for SSL connections. Default value is the key manager factory algorithm configured for the Java Virtual Machine.
ssl.keystore.location
Type: string
Default: null
Importance: medium
Dynamic update: per-broker
The location of the key store file. This is optional for client and can be used for two-way authentication for client.
ssl.keystore.password
Type: password
Default: null
Importance: medium
Dynamic update: per-broker
The store password for the key store file. This is optional for client and only needed if ssl.keystore.location is configured.
ssl.keystore.type
Type: string
Default: JKS
Importance: medium
Dynamic update: per-broker
The file format of the key store file. This is optional for client.
ssl.protocol
Type: string
Default: TLSv1.3
Importance: medium
Dynamic update: per-broker
The SSL protocol used to generate the SSLContext. The default is 'TLSv1.3' when running with Java 11 or newer, 'TLSv1.2' otherwise. This value should be fine for most use cases. Allowed values in recent JVMs are 'TLSv1.2' and 'TLSv1.3'. 'TLS', 'TLSv1.1', 'SSL', 'SSLv2' and 'SSLv3' may be supported in older JVMs, but their usage is discouraged due to known security vulnerabilities. With the default value for this config and 'ssl.enabled.protocols', clients will downgrade to 'TLSv1.2' if the server does not support 'TLSv1.3'. If this config is set to 'TLSv1.2', clients will not use 'TLSv1.3' even if it is one of the values in ssl.enabled.protocols and the server only supports 'TLSv1.3'.
ssl.provider
Type: string
Default: null
Importance: medium
Dynamic update: per-broker
The name of the security provider used for SSL connections. Default value is the default security provider of the JVM.
ssl.trustmanager.algorithm
Type: string
Default: PKIX
Importance: medium
Dynamic update: per-broker
The algorithm used by trust manager factory for SSL connections. Default value is the trust manager factory algorithm configured for the Java Virtual Machine.
ssl.truststore.location
Type: string
Default: null
Importance: medium
Dynamic update: per-broker
The location of the trust store file.
ssl.truststore.password
Type: password
Default: null
Importance: medium
Dynamic update: per-broker
The password for the trust store file. If a password is not set access to the truststore is still available, but integrity checking is disabled.
ssl.truststore.type
Type: string
Default: JKS
Importance: medium
Dynamic update: per-broker
The file format of the trust store file.
zookeeper.clientCnxnSocket
Type: string
Default: null
Importance: medium
Dynamic update: read-only
Typically set to
org.apache.zookeeper.ClientCnxnSocketNetty
when using TLS connectivity to ZooKeeper. Overrides any explicit value set via the same-namedzookeeper.clientCnxnSocket
system property.zookeeper.ssl.client.enable
Type: boolean
Default: false
Importance: medium
Dynamic update: read-only
Set client to use TLS when connecting to ZooKeeper. An explicit value overrides any value set via the
zookeeper.client.secure
system property (note the different name). Defaults to false if neither is set; when true,zookeeper.clientCnxnSocket
must be set (typically toorg.apache.zookeeper.ClientCnxnSocketNetty
); other values to set may includezookeeper.ssl.cipher.suites
,zookeeper.ssl.crl.enable
,zookeeper.ssl.enabled.protocols
,zookeeper.ssl.endpoint.identification.algorithm
,zookeeper.ssl.keystore.location
,zookeeper.ssl.keystore.password
,zookeeper.ssl.keystore.type
,zookeeper.ssl.ocsp.enable
,zookeeper.ssl.protocol
,zookeeper.ssl.truststore.location
,zookeeper.ssl.truststore.password
,zookeeper.ssl.truststore.type
.zookeeper.ssl.keystore.location
Type: string
Default: null
Importance: medium
Dynamic update: read-only
Keystore location when using a client-side certificate with TLS connectivity to ZooKeeper. Overrides any explicit value set via the
zookeeper.ssl.keyStore.location
system property (note the camelCase).zookeeper.ssl.keystore.password
Type: password
Default: null
Importance: medium
Dynamic update: read-only
Keystore password when using a client-side certificate with TLS connectivity to ZooKeeper. Overrides any explicit value set via the
zookeeper.ssl.keyStore.password
system property (note the camelCase). Note that ZooKeeper does not support a key password different from the keystore password, so be sure to set the key password in the keystore to be identical to the keystore password; otherwise the connection attempt to Zookeeper will fail.zookeeper.ssl.keystore.type
Type: string
Default: null
Importance: medium
Dynamic update: read-only
Keystore type when using a client-side certificate with TLS connectivity to ZooKeeper. Overrides any explicit value set via the
zookeeper.ssl.keyStore.type
system property (note the camelCase). The default value ofnull
means the type will be auto-detected based on the filename extension of the keystore.zookeeper.ssl.truststore.location
Type: string
Default: null
Importance: medium
Dynamic update: read-only
Truststore location when using TLS connectivity to ZooKeeper. Overrides any explicit value set via the
zookeeper.ssl.trustStore.location
system property (note the camelCase).zookeeper.ssl.truststore.password
Type: password
Default: null
Importance: medium
Dynamic update: read-only
Truststore password when using TLS connectivity to ZooKeeper. Overrides any explicit value set via the
zookeeper.ssl.trustStore.password
system property (note the camelCase).zookeeper.ssl.truststore.type
Type: string
Default: null
Importance: medium
Dynamic update: read-only
Truststore type when using TLS connectivity to ZooKeeper. Overrides any explicit value set via the
zookeeper.ssl.trustStore.type
system property (note the camelCase). The default value ofnull
means the type will be auto-detected based on the filename extension of the truststore.alter.config.policy.class.name
Type: class
Default: null
Importance: low
Dynamic update: read-only
The alter configs policy class that should be used for validation. The class should implement the
org.apache.kafka.server.policy.AlterConfigPolicy
interface.alter.log.dirs.replication.quota.window.num
Type: int
Default: 11
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The number of samples to retain in memory for alter log dirs replication quotas.
alter.log.dirs.replication.quota.window.size.seconds
Type: int
Default: 1
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The time span of each sample for alter log dirs replication quotas.
authorizer.class.name
Type: string
Default: ""
Importance: low
Dynamic update: read-only
The fully qualified name of a class that implements sorg.apache.kafka.server.authorizer.Authorizer interface, which is used by the broker for authorization. This config also supports authorizers that implement the deprecated kafka.security.auth.Authorizer trait which was previously used for authorization.
client.quota.callback.class
Type: class
Default: null
Importance: low
Dynamic update: read-only
The fully qualified name of a class that implements the ClientQuotaCallback interface, which is used to determine quota limits applied to client requests. By default, <user, client-id>, <user> or <client-id> quotas stored in ZooKeeper are applied. For any given request, the most specific quota that matches the user principal of the session and the client-id of the request is applied.
connection.failed.authentication.delay.ms
Type: int
Default: 100
Valid Values: [0,…]
Importance: low
Dynamic update: read-only
Connection close delay on failed authentication: this is the time (in milliseconds) by which connection close will be delayed on authentication failure. This must be configured to be less than connections.max.idle.ms to prevent connection timeout.
create.topic.policy.class.name
Type: class
Default: null
Importance: low
Dynamic update: read-only
The create topic policy class that should be used for validation. The class should implement the
org.apache.kafka.server.policy.CreateTopicPolicy
interface.delegation.token.expiry.check.interval.ms
Type: long
Default: 3600000 (1 hour)
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
Scan interval to remove expired delegation tokens.
kafka.metrics.polling.interval.secs
Type: int
Default: 10
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The metrics polling interval (in seconds) which can be used in kafka.metrics.reporters implementations.
kafka.metrics.reporters
Type: list
Default: ""
Importance: low
Dynamic update: read-only
A list of classes to use as Yammer metrics custom reporters. The reporters should implement
kafka.metrics.KafkaMetricsReporter
trait. If a client wants to expose JMX operations on a custom reporter, the custom reporter needs to additionally implement an MBean trait that extendskafka.metrics.KafkaMetricsReporterMBean
trait so that the registered MBean is compliant with the standard MBean convention.listener.security.protocol.map
Type: string
Default: PLAINTEXT:PLAINTEXT,SSL:SSL,SASL_PLAINTEXT:SASL_PLAINTEXT,SASL_SSL:SASL_SSL
Importance: low
Dynamic update: per-broker
Map between listener names and security protocols. This must be defined for the same security protocol to be usable in more than one port or IP. For example, internal and external traffic can be separated even if SSL is required for both. Concretely, the user could define listeners with names INTERNAL and EXTERNAL and this property as:
INTERNAL:SSL,EXTERNAL:SSL
. As shown, key and value are separated by a colon and map entries are separated by commas. Each listener name should only appear once in the map. Different security (SSL and SASL) settings can be configured for each listener by adding a normalised prefix (the listener name is lowercased) to the config name. For example, to set a different keystore for the INTERNAL listener, a config with namelistener.name.internal.ssl.keystore.location
would be set. If the config for the listener name is not set, the config will fallback to the generic config (i.e.ssl.keystore.location
).log.message.downconversion.enable
Type: boolean
Default: true
Importance: low
Dynamic update: cluster-wide
This configuration controls whether down-conversion of message formats is enabled to satisfy consume requests. When set to
false
, broker will not perform down-conversion for consumers expecting an older message format. The broker responds withUNSUPPORTED_VERSION
error for consume requests from such older clients. This configurationdoes not apply to any message format conversion that might be required for replication to followers.metric.reporters
Type: list
Default: ""
Importance: low
Dynamic update: cluster-wide
A list of classes to use as metrics reporters. Implementing the
org.apache.kafka.common.metrics.MetricsReporter
interface allows plugging in classes that will be notified of new metric creation. The JmxReporter is always included to register JMX statistics.metrics.num.samples
Type: int
Default: 2
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The number of samples maintained to compute metrics.
metrics.recording.level
Type: string
Default: INFO
Importance: low
Dynamic update: read-only
The highest recording level for metrics.
metrics.sample.window.ms
Type: long
Default: 30000 (30 seconds)
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The window of time a metrics sample is computed over.
password.encoder.cipher.algorithm
Type: string
Default: AES/CBC/PKCS5Padding
Importance: low
Dynamic update: read-only
The Cipher algorithm used for encoding dynamically configured passwords.
password.encoder.iterations
Type: int
Default: 4096
Valid Values: [1024,…]
Importance: low
Dynamic update: read-only
The iteration count used for encoding dynamically configured passwords.
password.encoder.key.length
Type: int
Default: 128
Valid Values: [8,…]
Importance: low
Dynamic update: read-only
The key length used for encoding dynamically configured passwords.
password.encoder.keyfactory.algorithm
Type: string
Default: null
Importance: low
Dynamic update: read-only
The SecretKeyFactory algorithm used for encoding dynamically configured passwords. Default is PBKDF2WithHmacSHA512 if available and PBKDF2WithHmacSHA1 otherwise.
quota.window.num
Type: int
Default: 11
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The number of samples to retain in memory for client quotas.
quota.window.size.seconds
Type: int
Default: 1
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The time span of each sample for client quotas.
replication.quota.window.num
Type: int
Default: 11
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The number of samples to retain in memory for replication quotas.
replication.quota.window.size.seconds
Type: int
Default: 1
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The time span of each sample for replication quotas.
security.providers
Type: string
Default: null
Importance: low
Dynamic update: read-only
A list of configurable creator classes each returning a provider implementing security algorithms. These classes should implement the
org.apache.kafka.common.security.auth.SecurityProviderCreator
interface.ssl.endpoint.identification.algorithm
Type: string
Default: https
Importance: low
Dynamic update: per-broker
The endpoint identification algorithm to validate server hostname using server certificate.
ssl.engine.factory.class
Type: class
Default: null
Importance: low
Dynamic update: per-broker
The class of type org.apache.kafka.common.security.auth.SslEngineFactory to provide SSLEngine objects. Default value is org.apache.kafka.common.security.ssl.DefaultSslEngineFactory.
ssl.principal.mapping.rules
Type: string
Default: DEFAULT
Importance: low
Dynamic update: read-only
A list of rules for mapping from distinguished name from the client certificate to short name. The rules are evaluated in order and the first rule that matches a principal name is used to map it to a short name. Any later rules in the list are ignored. By default, distinguished name of the X.500 certificate will be the principal. For more details on the format please see security authorization and acls. Note that this configuration is ignored if an extension of KafkaPrincipalBuilder is provided by the
principal.builder.class
configuration.ssl.secure.random.implementation
Type: string
Default: null
Importance: low
Dynamic update: per-broker
The SecureRandom PRNG implementation to use for SSL cryptography operations.
transaction.abort.timed.out.transaction.cleanup.interval.ms
Type: int
Default: 10000 (10 seconds)
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The interval at which to rollback transactions that have timed out.
transaction.remove.expired.transaction.cleanup.interval.ms
Type: int
Default: 3600000 (1 hour)
Valid Values: [1,…]
Importance: low
Dynamic update: read-only
The interval at which to remove transactions that have expired due to
transactional.id.expiration.ms
passing.zookeeper.ssl.cipher.suites
Type: list
Default: null
Importance: low
Dynamic update: read-only
Specifies the enabled cipher suites to be used in ZooKeeper TLS negotiation (csv). Overrides any explicit value set via the
zookeeper.ssl.ciphersuites
system property (note the single word "ciphersuites"). The default value ofnull
means the list of enabled cipher suites is determined by the Java runtime being used.zookeeper.ssl.crl.enable
Type: boolean
Default: false
Importance: low
Dynamic update: read-only
Specifies whether to enable Certificate Revocation List in the ZooKeeper TLS protocols. Overrides any explicit value set via the
zookeeper.ssl.crl
system property (note the shorter name).zookeeper.ssl.enabled.protocols
Type: list
Default: null
Importance: low
Dynamic update: read-only
Specifies the enabled protocol(s) in ZooKeeper TLS negotiation (csv). Overrides any explicit value set via the
zookeeper.ssl.enabledProtocols
system property (note the camelCase). The default value ofnull
means the enabled protocol will be the value of thezookeeper.ssl.protocol
configuration property.zookeeper.ssl.endpoint.identification.algorithm
Type: string
Default: HTTPS
Importance: low
Dynamic update: read-only
Specifies whether to enable hostname verification in the ZooKeeper TLS negotiation process, with (case-insensitively) "https" meaning ZooKeeper hostname verification is enabled and an explicit blank value meaning it is disabled (disabling it is only recommended for testing purposes). An explicit value overrides any "true" or "false" value set via the
zookeeper.ssl.hostnameVerification
system property (note the different name and values; true implies https and false implies blank).zookeeper.ssl.ocsp.enable
Type: boolean
Default: false
Importance: low
Dynamic update: read-only
Specifies whether to enable Online Certificate Status Protocol in the ZooKeeper TLS protocols. Overrides any explicit value set via the
zookeeper.ssl.ocsp
system property (note the shorter name).zookeeper.ssl.protocol
Type: string
Default: TLSv1.2
Importance: low
Dynamic update: read-only
Specifies the protocol to be used in ZooKeeper TLS negotiation. An explicit value overrides any value set via the same-named
zookeeper.ssl.protocol
system property.zookeeper.sync.time.ms
Type: int
Default: 2000 (2 seconds)
Importance: low
Dynamic update: read-only
How far a ZK follower can be behind a ZK leader.