Kafka Connection
Description
The Kafka Connection holds all necessary configuration properties to connect to the apache Kafka event streaming platform.
Bootstrap Servers contains a list of host/port pairs to establish the initial connection to the Kafka cluster.
This list only impacts the initial hosts used to discover the full set of servers.
The list must be in the form host1:port1,host2:port2,...
Kafka protocol you can choose PLAINTEXT or SSL. Select SSL if you want to establish a secure TLS connection. (TLS V1.3 or TLS V1.2 will be used depending on the version the server supports)
If SSL is selected, then the Server authentication panel is displayed to configure authentication options:
- Server certificate: The server must authenticate itself against Orchestra. In the select box you can select a credential containing an X509 certificate used to authenticate the Kafka server. The server is expected to present this certificate or the presented certificate must be signed by this certificate.
- If you select Accept All Issuers and no specific server credential is selected then any valid certificate presented by the server is accepted. If Accept all issuers is not selected and no specific server credential is selected then the certificate presented by the server is expected to exist in the Orchestra truststore, or it must at least be signed by a certificate contained in the truststore.
- Verify Hostname: Host name verification, when enabled, is the process of checking attributes from the certificate that is presented by the server you are connecting to against the actual hostname or IP address of that server to ensure that you are indeed connecting to the correct server. The main reason for this check is to prevent man-in-the-middle attacks.
Client authentication select a client authentication method. You can choose one of
- NO_AUTH the client does not authenticate itself against the server.
- SASL_PLAIN username/password authentication. Use this only together with a secure (TLS) connection.
- SASL_SCRAM username/password authentication using the Salted Challenge Response Authentication Mechanism (SCRAM)
- SASL_OAUTH2 fetch a token from an authentication server and authenticate at the server using this token
- CERTIFICATE uses a key pair to authenticate against the server together with TLS.
Client credential: This field is displayed if you select a Client authetication type.
You must select a Credential of type Technical Login
- In case of CERTIFICATE auth, the Credential must contain a PKCS12 key pair used to authenticate against the server.
- In case of SASL_PLAIN (User/Password authentication) or SASL_SCRAM, the Credential must contain a username and a password.
- In case of SASL_OAUTH2, the Credential must contain a Credential containing a client id and a client secret used to authenticate against the identity provider.
Token endpoint This field is displayed if you select the client authentication type SASL_OAUTH2.
It must contain an URL to which requests will be made to get the JWT token used to authenticate against the Kafka broker.
The protocol must be HTTP or HTTPS_.
OAuth2 scope This field is displayed if you select the client authentication type SASL_OAUTH2.
It defines the level of access the Orchestra channel is granted to Kafka.
If provided, it should match one or more scopes configured in the identity provider.
Hash function This field is displayed if you select the client authentication type SASL_SCRAM.
You may select one of the hash functions SSH-256 or SSH-512
Additional properties
In the main panel you can configure most of the properties provided by the Kafka Java library to configure a Kafka client. There are two tabs Producer Properties and Consumer Properties.
info
Note that normally you do not need to configure these properties. To change a property, you must uncheck the Use default check box. You can then enter a value different from the given default value.
Producer Properties
If necessary the default values for the Kafka connection can be changed. If not customized the values remain at their default setting:
| Key | Description | Default Value |
|---|---|---|
| acks | The number of acknowledgments the producer requires the leader to have received before considering a request complete. This controls the durability of records that are sent. The following settings are allowed:
Note that enabling idempotence requires this config value to be 'all'. If conflicting configurations are set and idempotence is not explicitly enabled, idempotence is disabled. | all |
| batch.size | The producer will attempt to batch records together into fewer requests whenever multiple records are being sent to the same partition. This helps performance on both the client and the server. This configuration controls the default batch size in bytes. No attempt will be made to batch records larger than this size. Requests sent to brokers will contain multiple batches, one for each partition with data available to be sent. A small batch size will make batching less common and may reduce throughput (a batch size of zero will disable batching entirely). A very large batch size may use memory a bit more wastefully as we will always allocate a buffer of the specified batch size in anticipation of additional records. Note: This setting gives the upper bound of the batch size to be sent. If we have fewer than this many bytes accumulated for this partition, we will 'linger' for the | 16384 |
| buffer.memory | The total bytes of memory the producer can use to buffer records waiting to be sent to the server. If records are sent faster than they can be delivered to the server the producer will block for max.block.ms after which it will fail with an exception.This setting should correspond roughly to the total memory the producer will use, but is not a hard bound since not all memory the producer uses is used for buffering. Some additional memory will be used for compression (if compression is enabled) as well as for maintaining in-flight requests. | 33554432 |
| client.dns.lookup | Controls how the client uses DNS lookups. If set to use_all_dns_ips, connect to each returned IP address in sequence until a successful connection is established. After a disconnection, the next IP is used. Once all IPs have been used once, the client resolves the IP(s) from the hostname again (both the JVM and the OS cache DNS name lookups, however). If set to resolve_canonical_bootstrap_servers_only, resolve each bootstrap address into a list of canonical names. After the bootstrap phase, this behaves the same as use_all_dns_ips. | use_all_dns_ips |
| compression.gzip.level | The compression level to use if compression.type is set to gzip. | -1 |
| compression.lz4.level | The compression level to use if compression.type is set to lz4. | 9 |
| compression.type | The compression type for all data generated by the producer. The default is none (i.e. no compression). Valid values are none, gzip, snappy, lz4, or zstd. Compression is of full batches of data, so the efficacy of batching will also impact the compression ratio (more batching means better compression). | none |
| compression.zstd.level | The compression level to use if compression.type is set to zstd. | 3 |
| connections.max.idle.ms | Close idle connections after the number of milliseconds specified by this config. | 540000 |
| delivery.timeout.ms | An upper bound on the time to report success or failure after a call to send() returns. This limits the total time that a record will be delayed prior to sending, the time to await acknowledgement from the broker (if expected), and the time allowed for retriable send failures. The producer may report failure to send a record earlier than this config if either an unrecoverable error is encountered, the retries have been exhausted, or the record is added to a batch which reached an earlier delivery expiration deadline. The value of this config should be greater than or equal to the sum of request.timeout.ms and linger.ms. | 120000 |
| enable.idempotence | When set to 'true', the producer will ensure that exactly one copy of each message is written in the stream. If 'false', producer retries due to broker failures, etc., may write duplicates of the retried message in the stream. Note that enabling idempotence requires max.in.flight.requests.per.connection to be less than or equal to 5 (with message ordering preserved for any allowable value), retries to be greater than 0, and acks must be 'all'. Idempotence is enabled by default if no conflicting configurations are set. If conflicting configurations are set and idempotence is not explicitly enabled, idempotence is disabled. If idempotence is explicitly enabled and conflicting configurations are set, a | true |
| enable.metrics.push | Whether to enable pushing of client metrics to the cluster, if the cluster has a client metrics subscription which matches this client. | true |
| linger.ms | The producer groups together any records that arrive in between request transmissions into a single batched request. Normally this occurs only under load when records arrive faster than they can be sent out. However in some circumstances the client may want to reduce the number of requests even under moderate load. This setting accomplishes this by adding a small amount of artificial delay—that is, rather than immediately sending out a record, the producer will wait for up to the given delay to allow other records to be sent so that the sends can be batched together. This can be thought of as analogous to Nagle's algorithm in TCP. This setting gives the upper bound on the delay for batching: once we get batch.size worth of records for a partition it will be sent immediately regardless of this setting, however if we have fewer than this many bytes accumulated for this partition we will 'linger' for the specified time waiting for more records to show up. This setting defaults to 5 (i.e. 5ms delay). Increasing linger.ms=50, for example, would have the effect of reducing the number of requests sent but would add up to 50ms of latency to records sent in the absence of load.The default changed from 0 to 5 in Apache Kafka 4.0 as the efficiency gains from larger batches typically result in similar or lower producer latency despite the increased linger. | 5 |
| max.block.ms | The configuration controls how long the KafkaProducer's send(), partitionsFor(), initTransactions(), sendOffsetsToTransaction(), commitTransaction() and abortTransaction() methods will block. For send() this timeout bounds the total time waiting for both metadata fetch and buffer allocation (blocking in the user-supplied serializers or partitioner is not counted against this timeout). For partitionsFor() this timeout bounds the time spent waiting for metadata if it is unavailable. The transaction-related methods always block, but may timeout if the transaction coordinator could not be discovered or did not respond within the timeout. | 60000 |
| max.in.flight.requests.per.connection | The maximum number of unacknowledged requests the client will send on a single connection before blocking. Note that if this configuration is set to be greater than 1 and enable.idempotence is set to false, there is a risk of message reordering after a failed send due to retries (i.e., if retries are enabled); if retries are disabled or if enable.idempotence is set to true, ordering will be preserved. Additionally, enabling idempotence requires the value of this configuration to be less than or equal to 5, because broker only retains at most 5 batches for each producer. If the value is more than 5, previous batches may be removed on broker side. | 5 |
| max.request.size | The maximum size of a request in bytes. This setting will limit the number of record batches the producer will send in a single request to avoid sending huge requests. This is also effectively a cap on the maximum uncompressed record batch size. Note that the server has its own cap on the record batch size (after compression if compression is enabled) which may be different from this. | 1048576 |
| metadata.max.age.ms | The period of time in milliseconds after which we force a refresh of metadata even if we haven't seen any partition leadership changes to proactively discover any new brokers or partitions. | 300000 |
| metadata.max.idle.ms | Controls how long the producer will cache metadata for a topic that's idle. If the elapsed time since a topic was last produced to exceeds the metadata idle duration, then the topic's metadata is forgotten and the next access to it will force a metadata fetch request. | 300000 |
| metadata.recovery.rebootstrap.trigger.ms | If a client configured to rebootstrap using metadata.recovery.strategy=rebootstrap is unable to obtain metadata from any of the brokers in the last known metadata for this interval, client repeats the bootstrap process using bootstrap.servers configuration. | 300000 |
| metadata.recovery.strategy | Controls how the client recovers when none of the brokers known to it is available. If set to none, the client fails. If set to rebootstrap, the client repeats the bootstrap process using bootstrap.servers. Rebootstrapping is useful when a client communicates with brokers so infrequently that the set of brokers may change entirely before the client refreshes metadata. Metadata recovery is triggered when all last-known brokers appear unavailable simultaneously. Brokers appear unavailable when disconnected and no current retry attempt is in-progress. Consider increasing reconnect.backoff.ms and reconnect.backoff.max.ms and decreasing socket.connection.setup.timeout.ms and socket.connection.setup.timeout.max.ms for the client. Rebootstrap is also triggered if connection cannot be established to any of the brokers for metadata.recovery.rebootstrap.trigger.ms milliseconds or if server requests rebootstrap. | rebootstrap |
| metrics.num.samples | The number of samples maintained to compute metrics. | 2 |
| metrics.recording.level | The highest recording level for metrics. It has three levels for recording metrics - info, debug, and trace. INFO level records only essential metrics necessary for monitoring system performance and health. It collects vital data without gathering too much detail, making it suitable for production environments where minimal overhead is desired. DEBUG level records most metrics, providing more detailed information about the system's operation. It's useful for development and testing environments where you need deeper insights to debug and fine-tune the application. TRACE level records all possible metrics, capturing every detail about the system's performance and operation. It's best for controlled environments where in-depth analysis is required, though it can introduce significant overhead. | INFO |
| metrics.sample.window.ms | The window of time a metrics sample is computed over. | 30000 |
| partitioner.adaptive.partitioning.enable | When set to 'true', the producer will try to adapt to broker performance and produce more messages to partitions hosted on faster brokers. If 'false', the producer will try to distribute messages uniformly. Note: this setting has no effect if a custom partitioner is used. | true |
| partitioner.availability.timeout.ms | If a broker cannot process produce requests from a partition for partitioner.availability.timeout.ms time, the partitioner treats that partition as not available. If the value is 0, this logic is disabled. Note: this setting has no effect if a custom partitioner is used or partitioner.adaptive.partitioning.enable is set to 'false'. | 0 |
| partitioner.ignore.keys | When set to 'true' the producer won't use record keys to choose a partition. If 'false', producer would choose a partition based on a hash of the key when a key is present. Note: this setting has no effect if a custom partitioner is used. | false |
| receive.buffer.bytes | The size of the TCP receive buffer (SO_RCVBUF) to use when reading data. If the value is -1, the OS default will be used. | 32768 |
| reconnect.backoff.max.ms | The maximum amount of time in milliseconds to wait when reconnecting to a broker that has repeatedly failed to connect. If provided, the backoff per host will increase exponentially for each consecutive connection failure, up to this maximum. After calculating the backoff increase, 20% random jitter is added to avoid connection storms. | 1000 |
| reconnect.backoff.ms | The base amount of time to wait before attempting to reconnect to a given host. This avoids repeatedly connecting to a host in a tight loop. This backoff applies to all connection attempts by the client to a broker. This value is the initial backoff value and will increase exponentially for each consecutive connection failure, up to the reconnect.backoff.max.ms value. | 50 |
| request.timeout.ms | 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. This should be larger than replica.lag.time.max.ms (a broker configuration) to reduce the possibility of message duplication due to unnecessary producer retries. | 30000 |
| retries | Number of times to retry a request that fails with a transient error. Setting a value greater than zero will cause the client to resend any record whose send fails with a potentially transient error. Requests will be retried this many times until they succeed, fail with a non-transient error, or the delivery.timeout.ms expires. Note that this automatic retry will simply resend the same record upon receiving the error. Setting a value of zero will disable this automatic retry behaviour, so that the transient errors will be propagated to the application to be handled. Users should generally prefer to leave this config unset and instead use delivery.timeout.ms to control retry behavior.Enabling idempotence requires this config value to be greater than 0. If conflicting configurations are set and idempotence is not explicitly enabled, idempotence is disabled. Allowing retries while setting | 2147483647 |
| retry.backoff.max.ms | The maximum amount of time in milliseconds to wait when retrying a request to the broker that has repeatedly failed. If provided, the backoff per client will increase exponentially for each failed request, up to this maximum. To prevent all clients from being synchronized upon retry, a randomized jitter with a factor of 0.2 will be applied to the backoff, resulting in the backoff falling within a range between 20% below and 20% above the computed value. If retry.backoff.ms is set to be higher than retry.backoff.max.ms, then retry.backoff.max.ms will be used as a constant backoff from the beginning without any exponential increase | 1000 |
| retry.backoff.ms | The amount of time to wait before attempting to retry a failed request to a given topic partition. This avoids repeatedly sending requests in a tight loop under some failure scenarios. This value is the initial backoff value and will increase exponentially for each failed request, up to the retry.backoff.max.ms value. | 100 |
| send.buffer.bytes | The size of the TCP send buffer (SO_SNDBUF) to use when sending data. If the value is -1, the OS default will be used. | 131072 |
| socket.connection.setup.timeout.max.ms | The maximum amount of time the client will wait for the socket connection to be established. The connection setup timeout will increase exponentially for each consecutive connection failure up to this maximum. To avoid connection storms, a randomization factor of 0.2 will be applied to the timeout resulting in a random range between 20% below and 20% above the computed value. | 30000 |
| socket.connection.setup.timeout.ms | The amount of time the client will wait for the socket connection to be established. If the connection is not built before the timeout elapses, clients will close the socket channel. This value is the initial backoff value and will increase exponentially for each consecutive connection failure, up to the socket.connection.setup.timeout.max.ms value. | 10000 |
| transaction.two.phase.commit.enable | If set to true, then the broker is informed that the client is participating in two phase commit protocol and transactions that this client starts never expire. | false |
Consumer Properties
If necessary the default values for the Kafka connection can be changed. If not customized the values remain at their default setting:
| Key | Description | Default Value |
|---|---|---|
| allow.auto.create.topics | Allow automatic topic creation on the broker when subscribing to or assigning a topic. A topic being subscribed to will be automatically created only if the broker allows for it using auto.create.topics.enable broker configuration. | true |
| auto.offset.reset | What to do when there is no initial offset in Kafka or if the current offset does not exist any more on the server (e.g. because that data has been deleted):
Note that altering partition numbers while setting this config to latest may cause message delivery loss since producers could start to send messages to newly added partitions (i.e. no initial offsets exist yet) before consumers reset their offsets. | latest |
| check.crcs | Automatically check the CRC32 of the records consumed. This ensures no on-the-wire or on-disk corruption to the messages occurred. This check adds some overhead, so it may be disabled in cases seeking extreme performance. | true |
| client.dns.lookup | Controls how the client uses DNS lookups. If set to use_all_dns_ips, connect to each returned IP address in sequence until a successful connection is established. After a disconnection, the next IP is used. Once all IPs have been used once, the client resolves the IP(s) from the hostname again (both the JVM and the OS cache DNS name lookups, however). If set to resolve_canonical_bootstrap_servers_only, resolve each bootstrap address into a list of canonical names. After the bootstrap phase, this behaves the same as use_all_dns_ips. | use_all_dns_ips |
| client.rack | A rack identifier for this client. This can be any string value which indicates where this client is physically located. It corresponds with the broker config 'broker.rack' | |
| connections.max.idle.ms | Close idle connections after the number of milliseconds specified by this config. | 540000 |
| default.api.timeout.ms | Specifies the timeout (in milliseconds) for client APIs. This configuration is used as the default timeout for all client operations that do not specify a timeout parameter. | 60000 |
| enable.metrics.push | Whether to enable pushing of client metrics to the cluster, if the cluster has a client metrics subscription which matches this client. | true |
| exclude.internal.topics | Whether internal topics matching a subscribed pattern should be excluded from the subscription. It is always possible to explicitly subscribe to an internal topic. | true |
| fetch.max.bytes | The maximum amount of data the server should return for a fetch request. Records are fetched in batches by the consumer, 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 the consumer can make progress. As such, this is not a absolute maximum. The maximum record batch size accepted by the broker is defined via message.max.bytes (broker config) or max.message.bytes (topic config). A fetch request consists of many partitions, and there is another setting that controls how much data is returned for each partition in a fetch request - see max.partition.fetch.bytes. Note that there is a current limitation when performing remote reads from tiered storage (KIP-405) - only one partition out of the fetch request is fetched from the remote store (KAFKA-14915). Note also that the consumer performs multiple fetches in parallel. | 52428800 |
| fetch.max.wait.ms | The maximum amount of time the server will block before answering the fetch request there isn't sufficient data to immediately satisfy the requirement given by fetch.min.bytes. This config is used only for local log fetch. To tune the remote fetch maximum wait time, please refer to 'remote.fetch.max.wait.ms' broker config | 500 |
| fetch.min.bytes | The minimum amount of data the server should return for a fetch request. If insufficient data is available the request will wait for that much data to accumulate before answering the request. The default setting of 1 byte means that fetch requests are answered as soon as that many byte(s) of data is available or the fetch request times out waiting for data to arrive. Setting this to a larger value will cause the server to wait for larger amounts of data to accumulate which can improve server throughput a bit at the cost of some additional latency. | 1 |
| group.instance.id | A unique identifier of the consumer instance provided by the end user. Only non-empty strings are permitted. If set, the consumer is treated as a static member, which means that only one instance with this ID is allowed in the consumer group at any time. This can be used in combination with a larger session timeout to avoid group rebalances caused by transient unavailability (e.g. process restarts). If not set, the consumer will join the group as a dynamic member, which is the traditional behavior. | |
| group.protocol | The group protocol consumer should use. We currently support "classic" or "consumer". If "consumer" is specified, then the consumer group protocol will be used. Otherwise, the classic group protocol will be used. | classic |
| group.remote.assignor | The name of the server-side assignor to use. If not specified, the group coordinator will pick the first assignor defined in the broker config group.consumer.assignors.This configuration is applied only if group.protocol is set to "consumer". | |
| heartbeat.interval.ms | The expected time between heartbeats to the consumer coordinator when using Kafka's group management facilities. Heartbeats are used to ensure that the consumer's session stays active and to facilitate rebalancing when new consumers join or leave the group. This config is only supported if group.protocol is set to "classic". In that case, the value must be set lower than session.timeout.ms, but typically should be set no higher than 1/3 of that value. It can be adjusted even lower to control the expected time for normal rebalances.If group.protocol is set to "consumer", this config is not supported, as the heartbeat interval is controlled by the broker with group.consumer.heartbeat.interval.ms. | 3000 |
| isolation.level | Controls how to read messages written transactionally. If set to read_committed, consumer.poll() will only return transactional messages which have been committed. If set to read_uncommitted (the default), consumer.poll() will return all messages, even transactional messages which have been aborted. Non-transactional messages will be returned unconditionally in either mode. Messages will always be returned in offset order. Hence, in Further, when in | read_uncommitted |
| max.partition.fetch.bytes | The maximum amount of data per-partition the server will return. Records are fetched in batches by the consumer. If the first record batch in the first non-empty partition of the fetch is larger than this limit, the batch will still be returned to ensure that the consumer can make progress. The maximum record batch size accepted by the broker is defined via message.max.bytes (broker config) or max.message.bytes (topic config). See fetch.max.bytes for limiting the consumer request size. Consider increasing max.partition.fetch.bytes especially in the cases of remote storage reads (KIP-405), because currently only one partition per fetch request is served from the remote store (KAFKA-14915). | 1048576 |
| max.poll.records | The maximum number of records returned in a single call to poll(). Note, that max.poll.records does not impact the underlying fetching behavior. The consumer will cache the records from each fetch request and returns them incrementally from each poll. | 500 |
| metadata.max.age.ms | The period of time in milliseconds after which we force a refresh of metadata even if we haven't seen any partition leadership changes to proactively discover any new brokers or partitions. | 300000 |
| metadata.recovery.rebootstrap.trigger.ms | If a client configured to rebootstrap using metadata.recovery.strategy=rebootstrap is unable to obtain metadata from any of the brokers in the last known metadata for this interval, client repeats the bootstrap process using bootstrap.servers configuration. | 300000 |
| metadata.recovery.strategy | Controls how the client recovers when none of the brokers known to it is available. If set to none, the client fails. If set to rebootstrap, the client repeats the bootstrap process using bootstrap.servers. Rebootstrapping is useful when a client communicates with brokers so infrequently that the set of brokers may change entirely before the client refreshes metadata. Metadata recovery is triggered when all last-known brokers appear unavailable simultaneously. Brokers appear unavailable when disconnected and no current retry attempt is in-progress. Consider increasing reconnect.backoff.ms and reconnect.backoff.max.ms and decreasing socket.connection.setup.timeout.ms and socket.connection.setup.timeout.max.ms for the client. Rebootstrap is also triggered if connection cannot be established to any of the brokers for metadata.recovery.rebootstrap.trigger.ms milliseconds or if server requests rebootstrap. | rebootstrap |
| metrics.num.samples | The number of samples maintained to compute metrics. | 2 |
| metrics.recording.level | The highest recording level for metrics. It has three levels for recording metrics - info, debug, and trace. INFO level records only essential metrics necessary for monitoring system performance and health. It collects vital data without gathering too much detail, making it suitable for production environments where minimal overhead is desired. DEBUG level records most metrics, providing more detailed information about the system's operation. It's useful for development and testing environments where you need deeper insights to debug and fine-tune the application. TRACE level records all possible metrics, capturing every detail about the system's performance and operation. It's best for controlled environments where in-depth analysis is required, though it can introduce significant overhead. | INFO |
| metrics.sample.window.ms | The window of time a metrics sample is computed over. | 30000 |
| receive.buffer.bytes | The size of the TCP receive buffer (SO_RCVBUF) to use when reading data. If the value is -1, the OS default will be used. | 65536 |
| reconnect.backoff.max.ms | The maximum amount of time in milliseconds to wait when reconnecting to a broker that has repeatedly failed to connect. If provided, the backoff per host will increase exponentially for each consecutive connection failure, up to this maximum. After calculating the backoff increase, 20% random jitter is added to avoid connection storms. | 1000 |
| reconnect.backoff.ms | The base amount of time to wait before attempting to reconnect to a given host. This avoids repeatedly connecting to a host in a tight loop. This backoff applies to all connection attempts by the client to a broker. This value is the initial backoff value and will increase exponentially for each consecutive connection failure, up to the reconnect.backoff.max.ms value. | 50 |
| request.timeout.ms | 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. | 30000 |
| retry.backoff.max.ms | The maximum amount of time in milliseconds to wait when retrying a request to the broker that has repeatedly failed. If provided, the backoff per client will increase exponentially for each failed request, up to this maximum. To prevent all clients from being synchronized upon retry, a randomized jitter with a factor of 0.2 will be applied to the backoff, resulting in the backoff falling within a range between 20% below and 20% above the computed value. If retry.backoff.ms is set to be higher than retry.backoff.max.ms, then retry.backoff.max.ms will be used as a constant backoff from the beginning without any exponential increase | 1000 |
| retry.backoff.ms | The amount of time to wait before attempting to retry a failed request to a given topic partition. This avoids repeatedly sending requests in a tight loop under some failure scenarios. This value is the initial backoff value and will increase exponentially for each failed request, up to the retry.backoff.max.ms value. | 100 |
| send.buffer.bytes | The size of the TCP send buffer (SO_SNDBUF) to use when sending data. If the value is -1, the OS default will be used. | 131072 |
| session.timeout.ms | The timeout used to detect client failures when using Kafka's group management facility. The client sends periodic heartbeats to indicate its liveness to the broker. If no heartbeats are received by the broker before the expiration of this session timeout, then the broker will remove this client from the group and initiate a rebalance. Note that the value must be in the allowable range as configured in the broker configuration by group.min.session.timeout.ms and group.max.session.timeout.ms. Note that this client configuration is not supported when group.protocol is set to "consumer". In that case, session timeout is controlled by the broker config group.consumer.session.timeout.ms. | 45000 |
| share.acknowledgement.mode | Controls the acknowledgement mode for a share consumer. If set to implicit, delivery is acknowledged implicitly on the next call to poll or commit. If set to explicit, it must use ShareConsumer.acknowledge() to acknowledge delivery of records. | implicit |
| socket.connection.setup.timeout.max.ms | The maximum amount of time the client will wait for the socket connection to be established. The connection setup timeout will increase exponentially for each consecutive connection failure up to this maximum. To avoid connection storms, a randomization factor of 0.2 will be applied to the timeout resulting in a random range between 20% below and 20% above the computed value. | 30000 |
| socket.connection.setup.timeout.ms | The amount of time the client will wait for the socket connection to be established. If the connection is not built before the timeout elapses, clients will close the socket channel. This value is the initial backoff value and will increase exponentially for each consecutive connection failure, up to the socket.connection.setup.timeout.max.ms value. | 10000 |
See also
See Security on how to define a users credentials.