Client Deprecation in Confluent Cloud¶
The Apache Kafka® 3.7 distribution released in Q1, 2024 included KIP-896. KIP-896 is the proposal to remove support for older client protocol API versions in Kafka 4.0. The 3.7 release marked these older, client protocol API versions deprecated with a notice that they will be completely dropped by 4.0. This page discusses the changes in Confluent client behavior resulting from KIP-896.
Starting February 2026, deprecated client requests will no longer be accepted and will result in errors. Confluent provides one year of extended compatibility, for customers’ Confluent Cloud clusters in existing organizations.
Minimal compatible baseline¶
With the release of Kafka 4.0 in 2025, Confluent sets the new baseline for client protocol API versions to Kafka 2.1.0, which was released in November 2018. As a result, clients connecting to new brokers must use compatible API versions.
The following chart describes the minimal compatible versions of some popular client libraries:
| Client | Version | Released |
|---|---|---|
| Java client for Kafka | 2.1.0 | November 2018 |
| Python (confluent-kafka-python) | 1.8.2 | October 2021 |
| .NET (confluent-kafka-dotnet) | 1.8.2 | October 2021 |
| JavaScript (confluent-kafka-javascript) | 1.8.2 | October 2021 |
| Go (confluent-kafka-go) | 1.8.2 | October 2021 |
| C/C++ (librdkafka) | 1.8.2 | October 2021 |
| KafkaJS | 1.15.0 | November 2020 |
| Sarama | 1.29.1 | June 2021 |
| kafka-python | 2.0.2 | Sep 2020 |
Any librdkafka-based protocols not listed in the preceding table have a version minimum of 1.8.2 as specified in the October 2021 release of Apache Kafka®.
List of deprecated Kafka APIs¶
| API | Deprecated version |
|---|---|
| Produce | V0-V2 |
| Fetch | V0-V3 |
| ListOffset | V0 |
| Metadata | None |
| OffsetCommit | V0-V1 |
| OffsetFetch | V0 |
| FindCoordinator | None |
| JoinGroup | V0-V1 |
| Heartbeat | V0-V1 |
| LeaveGroup | None |
| SyncGroup | None |
| DescribeGroups | None |
| ListGroups | None |
| SaslHandshake | None |
| ApiVersions | None |
| CreateTopics | V0-V1 |
| DeleteTopics | V0 |
| DeleteRecords | None |
| InitProducerId | None |
| OffsetForLeaderEpoch | V0-V1 |
| AddPartitionsToTxn | None |
| AddOffsetsToTxn | None |
| EndTxn | None |
| WriteTxnMarkers | None |
| TxnOffsetCommit | None |
| DescribeAcls | V0 |
| CreateAcls | V0 |
| DeleteAcls | V0 |
| DescribeConfigs | V0 |
| AlterConfigs | None |
| AlterReplicaLogDirs | V0 |
| DescribeLogDirs | V0 |
| SaslAuthenticate | None |
| CreatePartitions | None |
| CreateDelegationToken | V0 |
| RenewDelegationToken | V0 |
| ExpireDelegationToken | V0 |
| DescribeDelegationToken: | V0 |
| DeleteGroups | None |
Recommended upgrades based on client ID¶
Many Kafka clients many not report their official software library or version in their requests. If this is the case, you must inspect a client’s clientId to identify the client type. Some client software embed recognizable identifiers, others do not. Further, some client identifiers have custom formats making it hard to determine their version or library.
The following list provides some examples of client IDs, the likely client type given the ID, and the actions you can take to upgrade the corresponding client:
| Client ID resembles | What type of client? | Suggested action to try |
|---|---|---|
producer-X or consumer-X |
Possibly a Java producer/consumer using the default clientId. The client could can be anything if the customer manually created the clientId. |
If a Java client, upgrade to the latest Java client version. |
beats or filebeats |
Possibly an Elastic’s filebeats product using the Sarama Kafka client under-the-hood. | Base your approach on the beats version. If the version is 7.X or higher, try to resolve the problem with a change in the version configuration to a value of 2.1.0 or higher. If you are using a version older than 7.X, upgrade to the latest version of beats. |
(some-string)- ( github.com/segmentio/kafka-go ) |
A kafka-go library
client maintained by Segment. |
The latest version of segmentio/kafka-go is currently not compliant for consumer applications. Confluent has raised an issue with the project to help remediate this flaw. Customers should use the latest version of the confluent-kafka-go library
which is compliant. |
sarama |
Sarama, a go client maintained by IBM. Sarama serves as the underlying client for other tools like beats | Upgrade to at least 1.29.1 and make sure that the Kafka is set to at least the 2.1.1 version. |
rdkafka or rdkafka-producer |
This client either be a Confluent maintained or a third-party client that uses librdkafka under the hood, for example, rdkafka is used as a default clientId. |
Upgrade to at least the librdkafka library’s 1.8.2 version. Ideally use the latest version. |
kafka-python-producer-X or kafka-python-consumer-X or kafka-python-X.Y.Z |
A popular Python library for Kafka (kafka-python). |
Upgrade to the latest version. |
Kafka-node-client |
A popular JS library for Kafka (kafka-node). |
No longer maintained. Try a different library such as confluent-kafka-javascript or KafkaJS. Though, KafkaJS is also not maintained. |
kaffe_producer_client |
Likely to be the “Kaffe” Kafka elixir client | As this library appears to be inconsistently maintained, consider moving to something with more maintenance such as the kafka_ex:master branch. |
aiokafka or aiokafka-producer-X |
The aiokafka Python client library | Upgrade to the latest version. |
faust and faust-X.Y.Z |
The faust library which serves as a Python alternative for Kafka Streams. | Upgrade to the latest version. |
ruby-kafka |
Possibly the Zendesk “ruby-kafka” client. | This client is officially deprecated by Zendesk. Consider another Ruby Kafka client such as the karafka/rdkafka-ruby client which a third- maintains. |