Cloudera Docs

Known Issues in Apache Kafka

Learn about the known issues in Apache Kafka, the impact or changes to the functionality, and the workaround.

Known Issues

OPSAPS-59553: SMM's bootstrap server config should be updated based on Kafka's listeners

SMM does not show any metrics for Kafka or Kafka Connect when multiple listeners are set in Kafka.

Workaround: SMM cannot identify multiple listeners and still points to bootstrap server using the default broker port (9093 for SASL_SSL). You would have to override bootstrap server URL (hostname:port as set in the listeners for broker) in the following path:

Cloudera Manager > SMM > Configuration > Streams Messaging Manager Rest Admin Server Advanced Configuration Snippet (Safety Valve) for streams-messaging-manager.yaml > Save Changes > Restart SMM.

The offsets.topic.replication.factor property must be less than or equal to the number of live brokers
The offsets.topic.replication.factor broker configuration is now enforced upon auto topic creation. Internal auto topic creation will fail with a GROUP_COORDINATOR_NOT_AVAILABLE error until the cluster size meets this replication factor requirement.
None
Requests fail when sending to a nonexistent topic with auto.create.topics.enable set to true
The first few produce requests fail when sending to a nonexistent topic with auto.create.topics.enable set to true.
Increase the number of retries in the producer configuration setting retries.
KAFKA-2561: Performance degradation when SSL Is enabled
In some configuration scenarios, significant performance degradation can occur when SSL is enabled. The impact varies depending on your CPU, JVM version, Kafka configuration, and message size. Consumers are typically more affected than producers.
Configure brokers and clients with ssl.secure.random.implementation = SHA1PRNG. It often reduces this degradation drastically, but its effect is CPU and JVM dependent.
OPSAPS-43236: Kafka garbage collection logs are written to the process directory
By default Kafka garbage collection logs are written to the agent process directory. Changing the default path for these log files is currently unsupported.
None
CDPD-45183: Kafka Connect active topics might be visible to unauthorised users
The Kafka Connect active topics endpoint (/connectors/[***CONNECTOR NAME***]/topics) and the Connect Cluster page on the SMM UI disregard the user permissions configured for the Kafka service in Ranger. As a result, all active topics of connectors might become visible to users who do not have permissions to view them. Note that user permission configured for Kafka Connect in Ranger are not affected by this issue and are correctly applied.
None.
OPSAPS-65485: Selecting the Require Connectors To Override Kafka Client JAAS Configuration property causes automatic Kafka Connect startup retries to fail
If the Require Connectors To Override Kafka Client JAAS Configuration property is selected for the Kafka Connect role and the role fails to start due to any reason, all automatic retries to start the role will also fail. This is true even if the root cause of the initial startup failure was caused by an intermittent issue.
Review the Kafka connect logs and resolve the root cause of the startup failure. Once the issue is resolved, restart the Kafka Connect role manually. Alternatively, clear the Require Connectors To Override Kafka Client JAAS Configuration property.
RANGER-3809: Idempotent Kafka producer fails to initialize due to an authorization failure
Kafka producers that have idempotence enabled require the Idempotent Write permission to be set on the cluster resource in Ranger. If permission is not given, the client fails to initialize and an error similar to the following is thrown: 
org.apache.kafka.common.KafkaException: Cannot execute transactional method because we are in an error state
    at org.apache.kafka.clients.producer.internals.TransactionManager.maybeFailWithError(TransactionManager.java:1125)
    at org.apache.kafka.clients.producer.internals.TransactionManager.maybeAddPartition(TransactionManager.java:442)
    at org.apache.kafka.clients.producer.KafkaProducer.doSend(KafkaProducer.java:1000)
    at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:914)
    at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:800)
    .
    .
    .
Caused by: org.apache.kafka.common.errors.ClusterAuthorizationException: Cluster authorization failed.
Idempotence is enabled by default for clients in Kafka 3.0.1, 3.1.1, and any version after 3.1.1. This means that any client updated to 3.0.1, 3.1.1, or any version after 3.1.1 is affected by this issue.
This issue has two workarounds, do either of the following:
  • Explicitly disable idempotence for the producers. This can be done by setting enable.idempotence to false.
  • Update your policies in Ranger and ensure that producers have Idempotent Write permission on the cluster resource.
CDPD-29307: Kafka producer entity stays in incomplete state in Atlas
Atlas creates incomplete Kafka client entities that are postfixed with the metadata namespace.
None
DBZ-4990: The Debezium Db2 Source connector does not support schema evolution
The Debezium Db2 Source connector does not support the evolution (updates) of schemas. In addition, schema change events are not emitted to the schema change topic if there is a change in the schema of a table that is in capture mode. For more information, see DBZ-4990.
None.
CDPD-53179: Amazon S3 sink connector fails when buffer size is reached
If there is more than 5 MB (buffer size) of data available in a Kafka source topic and the connector receives more than 5 MB of data in a single poll, the connector tries to upload all the data as a multipart upload to S3. The upload, however, fails.
Decrease the Offset Flush Interval Kafka service property. Decreasing the value of this property increases how frequently connectors commit data. If the connectors commit more frequently, each commit will contain less data. Cloudera advises caution if you decide to change the value of this property because:
  • The interval you configure is applied to all Kafka Connect connectors.
  • Decreasing the interval might result in an increased number of files created in S3.
CDPD-48822: AvroConverter ignores default values when converting from Avro to Connect schema
AvroConverter does not propagate field default values when converting Avro schemas to Connect schemas.
None

Unsupported Features

The following Kafka features are not supported in Cloudera Data Platform:
  • Only Java and .Net based clients are supported. Clients developed with C, C++, Python, and other languages are currently not supported.
  • The Kafka default authorizer is not supported. This includes setting ACLs and all related APIs, broker functionality, and command-line tools.
  • SASL/SCRAM is only supported for delegation token based authentication. It is not supported as a standalone authentication mechanism.
  • The Cloudera AvroConverter (com.cloudera.dim.kafka.connect.converts.AvroConverter) is not supported with the Debezium Kafka Connect connectors shipped in Cloudera Runtime.

Limitations

Collection of Partition Level Metrics May Cause Cloudera Manager’s Performance to Degrade

If the Kafka service operates with a large number of partitions, collection of partition level metrics may cause Cloudera Manager's performance to degrade.

If you are observing performance degradation and your cluster is operating with a high number of partitions, you can choose to disable the collection of partition level metrics.
Complete the following steps to turn off the collection of partition level metrics:
  1. Obtain the Kafka service name:
    1. In Cloudera Manager, Select the Kafka service.
    2. Select any available chart, and select Open in Chart Builder from the configuration icon drop-down.
    3. Find $SERVICENAME= near the top of the display.
      The Kafka service name is the value of $SERVICENAME.
  2. Turn off the collection of partition level metrics:
    1. Go to Hosts > Hosts Configuration.
    2. Find and configure the Cloudera Manager Agent Monitoring Advanced Configuration Snippet (Safety Valve) configuration property.
      Enter the following to turn off the collection of partition level metrics:
      [KAFKA_SERVICE_NAME]_feature_send_broker_topic_partition_entity_update_enabled=false
      Replace [KAFKA_SERVICE_NAME] with the service name of Kafka obtained in step 1. The service name should always be in lower case.
    3. Click Save Changes.