Is there a way to purge the topic in Kafka?

Question

I pushed a message that was too big into a kafka message topic on my local machine, now I'm getting an error:

kafka.common.InvalidMessageSizeException: invalid message size

Increasing the fetch.size is not ideal here, because I don't actually want to accept messages that big.

Answer 1

I have read almost all of the answers, we are using Kafka Kraft 3.4.0. so I can maybe add one answer for Kraft. It is not really different how to do this on Kraft, you will need a machine which can use the bootstrap servers of kafka with kafka binaries on it do:

bin/kafka-configs.sh --bootstrap-server :9092 --entity-type topics --entity-name your-topic --alter --add-config retention.ms=1000

The problem here is that log retention as time is not really the only thing kafka looks when deleting logs from the filesystem. You also need to consider the log segment bytes. Kafka rolls up segments when the log sizes on disk reach to segment.bytes for the partition in hand, if you have an open partition offset still haven't rolled up it is not going to be deleted even if you set the retention.ms to 1 milisecond.

If you are looking for a way to clear a topic with lets say messages are 2000 bytes each;

set segment.bytes:

bin/kafka-configs.sh --bootstrap-server :9092 --entity-type topics --entity-name your-topic --alter --add-config segment.bytes=<smaller than 1 message's total bytes>

set retention.ms:

bin/kafka-configs.sh --bootstrap-server :9092 --entity-type topics --entity-name your-topic --alter --add-config retention.ms=1000

And keep in mind it is NOT going to clear magically in 1 second, the delete retention period should be triggered in a second BUT the rollups of open ended segments will take more than that (close to 5 mins). So keep an eye on the log sizes on the brokers and reset these configs when you see log sizes are 0 for the topic:

/bin/kafka-configs.sh --bootstrap-server :9092 --entity-type topics --entity-name your-topic --delete-config segment.bytes
/bin/kafka-configs.sh --bootstrap-server :9092 --entity-type topics --entity-name your-topic --delete-config retention.ms

Answer 2

you have to enable this on config

echo "delete.topic.enable=true" >> /opt/kafka/config/server.properties 
sudo systemctl stop kafka 
sudo systemctl start kafka 

purge the topic

/opt/kafka/bin/kafka-topics.sh --bootstrap-server localhost:9092 --delete --topic flows

create the topic

# /opt/kafka/bin/kafka-topics.sh --create --bootstrap-server localhost:2181 --replication-factor 1 --partitions 1 --topic Test

read the topic

# /opt/kafka/bin/kafka-console-consumer.sh  localhost:9092 --topic flows --from-beginning

Answer 3

Besides updating retention.ms and retention.bytes, I noticed topic cleanup policy should be "delete" (default), if "compact", it is going to hold on to messages longer, i.e., if it is "compact", you have to specify delete.retention.ms also.

$ ./bin/kafka-configs.sh --zookeeper localhost:2181 --describe --entity-name test-topic-3-100 --entity-type topics
            
Configs for topics:test-topic-3-100 are retention.ms=1000,delete.retention.ms=10000,cleanup.policy=delete,retention.bytes=1

Also had to monitor earliest/latest offsets should be same to confirm this successfully happened, can also check the du -h /tmp/kafka-logs/test-topic-3-100-*

$ ./bin/kafka-run-class.sh kafka.tools.GetOffsetShell --broker-list "BROKER:9095" --topic test-topic-3-100 --time -1 | awk -F ":" '{sum += $3} END {print sum}'

26599762

$ ./bin/kafka-run-class.sh kafka.tools.GetOffsetShell --broker-list "BROKER:9095" --topic test-topic-3-100 --time -2 | awk -F ":" '{sum += $3} END {print sum}'

26599762

The other problem is, you have to get current config first so you remember to revert after deletion is successful: ./bin/kafka-configs.sh --zookeeper localhost:2181 --describe --entity-name test-topic-3-100 --entity-type topics

Answer 4

Sometimes, if you've a saturated cluster (too many partitions, or using encrypted topic data, or using SSL, or the controller is on a bad node, or the connection is flaky, it'll take a long time to purge said topic.

I follow these steps, particularly if you're using TLS.

1: Run with kafka tools :

kafka-configs.sh --alter --entity-type topics --zookeeper zookeeper01.kafka.com --add-config retention.ms=1 --entity-name <topic-name>

2: Run:

kafka-console-consumer --consumer-property security.protocol=SSL --consumer-property ssl.truststore.location=/etc/schema-registry/secrets/trust.jks --consumer-property ssl.truststore.password=password --consumer-property ssl.keystore.location=/etc/schema-registry/secrets/identity.jks --consumer-property ssl.keystore.password=password --consumer-property ssl.key.password=password --bootstrap-server broker01.kafka.com:9092 --topic <topic-name> --new-consumer --from-beginning

3: Set topic retention back to the original setting, once topic is empty.

kafka-configs.sh --alter --entity-type topics --zookeeper zookeeper01.kafka.com --add-config retention.ms=604800000 --entity-name <topic-name>

Hope this helps someone, as it isn't easily advertised.

Answer 5

Just in case someone is looking for an updated answer (in 2022), I found the following will work for Kafka version 3.3.1. This will change the configuration for "your-topic" so that messages are retained for 1000ms. After messages are purged, then you can set back to a different value.

bin/kafka-configs.sh --bootstrap-server localhost:9092 --entity-type topics --entity-name your-topic  --alter --add-config retention.ms=1000

Answer 6

I'm using Kafka 2.13 tools. Now --zookeeper is unrecognized option for kafka-topics.sh . To delete a topic:

bin/kafka-topics.sh --bootstrap-server [kafka broker]:9092 --delete --topic [topic name]

Just take into account that to create the same topic again you may need to way a while if you had a lot of data in the deleted topic. When you try to create the same topic, you may get the error:

ERROR org.apache.kafka.common.errors.TopicExistsException: Topic '[topic name]' is marked for deletion.

Answer 7

The workaround of temporarily reducing the retention time for a topic, suggested by user644265 in this answer still works but recent versions of kafka-configs will warn that the --zookeeper option has been deprecated:

Warning: --zookeeper is deprecated and will be removed in a future version of Kafka

Use --bootstrap-server instead; for example

kafka-configs --bootstrap-server localhost:9092 --alter --entity-type topics --entity-name my_topic --add-config retention.ms=100

and

kafka-configs --bootstrap-server localhost:9092 --alter --entity-type topics --entity-name my_topic --delete-config retention.ms

Answer 8

Here are the steps to follow to delete a topic named MyTopic:

1. Describe the topic, and take note of the broker ids
2. Stop the Apache Kafka daemon for each broker ID listed.
3. Connect to each broker (from step 1), and delete the topic data folder, e.g. rm -rf /tmp/kafka-logs/MyTopic-0. Repeat for other partitions, and all replicas
4. Delete the topic metadata: zkCli.sh then rmr /brokers/MyTopic
5. Start the Apache Kafka daemon for each stopped machine

---

If you miss you step 3, then Apache Kafka will continue to report the topic as present (for example when if you run kafka-list-topic.sh).

Tested with Apache Kafka 0.8.0.

Answer 9

if you are using confluentinc/cp-kafka containers here is the command to delete the topic.

docker exec -it <kafka-container-id> kafka-topics --zookeeper zookeeper:2181 --delete --topic <topic-name>

Success response:

Topic <topic-name> is marked for deletion.
Note: This will have no impact if delete.topic.enable is not set to true.

Answer 10

Tested in Kafka 0.8.2, for the quick-start example: First, Add one line to server.properties file under config folder:

delete.topic.enable=true

then, you can run this command:

bin/kafka-topics.sh --zookeeper localhost:2181 --delete --topic test

Then recreate it, for clients to continue operations against an empty topic

Answer 11

From kafka 1.1

Purge a topic

bin/kafka-configs.sh --zookeeper localhost:2181 --alter --entity-type topics --entity-name tp_binance_kline --add-config retention.ms=100

wait at least 1 minute, to be secure that kafka purge the topic remove the configuration, and then go to default value

bin/kafka-configs.sh --zookeeper localhost:2181 --alter --entity-type topics --entity-name tp_binance_kline --delete-config retention.ms

Answer 12

Temporarily update the retention time on the topic to one second:

kafka-topics.sh \
  --zookeeper <zkhost>:2181 \
  --alter \
  --topic <topic name> \
  --config retention.ms=1000

And in newer Kafka releases, you can also do it with kafka-configs --entity-type topics

kafka-configs.sh \
  --zookeeper <zkhost>:2181 \
  --entity-type topics \
  --alter \
  --entity-name <topic name> \
  --add-config retention.ms=1000

then wait for the purge to take effect (duration depends on size of the topic). Once purged, restore the previous retention.ms value.

Answer 13

If you want to do this programmatically within a Java Application you can use the AdminClient's API deleteRecords. Using the AdminClient allows you to delete records on a partition and offset level.

According to the JavaDocs this operation is supported by brokers with version 0.11.0.0 or higher.

Here is a simple example:

String brokers = "localhost:9092";
String topicName = "test";
TopicPartition topicPartition = new TopicPartition(topicName, 0);
RecordsToDelete recordsToDelete = RecordsToDelete.beforeOffset(5L);

Map<TopicPartition, RecordsToDelete> topicPartitionRecordToDelete = new HashMap<>();
topicPartitionRecordToDelete.put(topicPartition, recordsToDelete);

// Create AdminClient
final Properties properties = new Properties();
properties.put(AdminClientConfig.BOOTSTRAP_SERVERS_CONFIG, brokers);
AdminClient adminClient = AdminClient.create(properties);

try {
  adminClient.deleteRecords(topicPartitionRecordToDelete).all().get();
} catch (InterruptedException e) {
  e.printStackTrace();
} catch (ExecutionException e) {
  e.printStackTrace();
} finally {
  adminClient.close();
}

Answer 14

have you considered having your app simply use a new renamed topic? (i.e. a topic that is named like the original topic but with a "1" appended at the end).

That would also give your app a fresh clean topic.

Answer 15

Following command can be used to delete all the existing messages in kafka topic:

kafka-delete-records --bootstrap-server <kafka_server:port> --offset-json-file delete.json

The structure of the delete.json file should be following:

{ "partitions": [ { "topic": "foo", "partition": 1, "offset": -1 } ], "version": 1 }

where offset :-1 will delete all the records (This command has been tested with kafka 2.0.1

Answer 16

A lot of great answers over here but among them, I didn't find one about docker. I spent some time to figure out that using the broker container is wrong for this case (obviously!!!)

## this is wrong!
docker exec broker1 kafka-topics --zookeeper localhost:2181 --alter --topic mytopic --config retention.ms=1000

Exception in thread "main" kafka.zookeeper.ZooKeeperClientTimeoutException: Timed out waiting for connection while in state: CONNECTING
        at kafka.zookeeper.ZooKeeperClient.$anonfun$waitUntilConnected$3(ZooKeeperClient.scala:258)
        at scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:23)
        at kafka.utils.CoreUtils$.inLock(CoreUtils.scala:253)
        at kafka.zookeeper.ZooKeeperClient.waitUntilConnected(ZooKeeperClient.scala:254)
        at kafka.zookeeper.ZooKeeperClient.<init>(ZooKeeperClient.scala:112)
        at kafka.zk.KafkaZkClient$.apply(KafkaZkClient.scala:1826)
        at kafka.admin.TopicCommand$ZookeeperTopicService$.apply(TopicCommand.scala:280)
        at kafka.admin.TopicCommand$.main(TopicCommand.scala:53)
        at kafka.admin.TopicCommand.main(TopicCommand.scala)

and I should have used zookeeper:2181 instead of --zookeeper localhost:2181 as per my compose file

## this might be an option, but as per comment below not all zookeeper images can have this script included
docker exec zookeper1 kafka-topics --zookeeper localhost:2181 --alter --topic mytopic --config retention.ms=1000

the correct command would be

docker exec broker1 kafka-configs --zookeeper zookeeper:2181 --alter --entity-type topics --entity-name dev_gdn_urls --add-config retention.ms=12800000

Hope it will save someone's time.

Also, be aware that the messages won't be deleted immediately and it will happen when the segment of the log will be closed.

Answer 17

Following @steven appleyard answer I executed the following commands on Kafka 2.2.0 and they worked for me.

bin/kafka-configs.sh --zookeeper localhost:2181 --entity-type topics --entity-name <topic-name> --describe

bin/kafka-configs.sh --zookeeper localhost:2181 --entity-type topics --entity-name <topic-name> --alter --add-config retention.ms=1000

bin/kafka-configs.sh --zookeeper localhost:2181 --entity-type topics --entity-name <topic-name> --alter --delete-config retention.ms

Answer 18

From Java, using the new AdminZkClient instead of the deprecated AdminUtils:

  public void reset() {
    try (KafkaZkClient zkClient = KafkaZkClient.apply("localhost:2181", false, 200_000,
        5000, 10, Time.SYSTEM, "metricGroup", "metricType")) {

      for (Map.Entry<String, List<PartitionInfo>> entry : listTopics().entrySet()) {
        deleteTopic(entry.getKey(), zkClient);
      }
    }
  }

  private void deleteTopic(String topic, KafkaZkClient zkClient) {

    // skip Kafka internal topic
    if (topic.startsWith("__")) {
      return;
    }

    System.out.println("Resetting Topic: " + topic);
    AdminZkClient adminZkClient = new AdminZkClient(zkClient);
    adminZkClient.deleteTopic(topic);

    // deletions are not instantaneous
    boolean success = false;
    int maxMs = 5_000;
    while (maxMs > 0 && !success) {
      try {
        maxMs -= 100;
        adminZkClient.createTopic(topic, 1, 1, new Properties(), null);
        success = true;
      } catch (TopicExistsException ignored) {
      }
    }

    if (!success) {
      Assert.fail("failed to create " + topic);
    }
  }

  private Map<String, List<PartitionInfo>> listTopics() {
    Properties props = new Properties();
    props.put("bootstrap.servers", kafkaContainer.getBootstrapServers());
    props.put("group.id", "test-container-consumer-group");
    props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
    props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

    KafkaConsumer<String, String> consumer = new KafkaConsumer<>(props);
    Map<String, List<PartitionInfo>> topics = consumer.listTopics();
    consumer.close();

    return topics;
  }

Answer 19

./kafka-topics.sh --describe --zookeeper zkHost:2181 --topic myTopic

This should give retention.ms configured. Then you can use above alter command to change to 1second (and later revert back to default).

Topic:myTopic   PartitionCount:6        ReplicationFactor:1     Configs:retention.ms=86400000

Answer 20

Another, rather manual, approach for purging a topic is:

in the brokers:

1. stop kafka broker
   sudo service kafka stop
2. delete all partition log files (should be done on all brokers)
   sudo rm -R /kafka-storage/kafka-logs/<some_topic_name>-*

in zookeeper:

3. run zookeeper command line interface
   sudo /usr/lib/zookeeper/bin/zkCli.sh
4. use zkCli to remove the topic metadata
   rmr /brokers/topic/<some_topic_name>

in the brokers again:

5. restart broker service
   sudo service kafka start

Answer 21

UPDATE: This answer is relevant for Kafka 0.6. For Kafka 0.8 and later see answer by @Patrick.

Yes, stop kafka and manually delete all files from corresponding subdirectory (it's easy to find it in kafka data directory). After kafka restart the topic will be empty.

Answer 22

To clean up all the messages from a particular topic using your application group (GroupName should be same as application kafka group name).

./kafka-path/bin/kafka-console-consumer.sh --zookeeper localhost:2181 --topic topicName --from-beginning --group application-group

Answer 23

kafka don't have direct method for purge/clean-up topic (Queues), but can do this via deleting that topic and recreate it.

first of make sure sever.properties file has and if not add delete.topic.enable=true

then, Delete topic bin/kafka-topics.sh --zookeeper localhost:2181 --delete --topic myTopic

then create it again.

bin/kafka-topics.sh --zookeeper localhost:2181 --create --topic myTopic --partitions 10 --replication-factor 2

Answer 24

To purge the queue you can delete the topic:

bin/kafka-topics.sh --zookeeper localhost:2181 --delete --topic test

then re-create it:

bin/kafka-topics.sh --create --zookeeper localhost:2181 \
    --replication-factor 1 --partitions 1 --topic test

Answer 25

While the accepted answer is correct, that method has been deprecated. Topic configuration should now be done via kafka-configs.

kafka-configs --zookeeper localhost:2181 --entity-type topics --alter --add-config retention.ms=1000 --entity-name MyTopic

Configurations set via this method can be displayed with the command

kafka-configs --zookeeper localhost:2181 --entity-type topics --describe --entity-name MyTopic

Answer 26

Thomas' advice is great but unfortunately zkCli in old versions of Zookeeper (for example 3.3.6) do not seem to support rmr. For example compare the command line implementation in modern Zookeeper with version 3.3.

If you are faced with an old version of Zookeeper one solution is to use a client library such as zc.zk for Python. For people not familiar with Python you need to install it using pip or easy_install. Then start a Python shell (python) and you can do:

import zc.zk
zk = zc.zk.ZooKeeper('localhost:2181')
zk.delete_recursive('brokers/MyTopic') 

or even

zk.delete_recursive('brokers')

if you want to remove all the topics from Kafka.

Answer 27

The simplest approach is to set the date of the individual log files to be older than the retention period. Then the broker should clean them up and remove them for you within a few seconds. This offers several advantages:

1. No need to bring down brokers, it's a runtime operation.
2. Avoids the possibility of invalid offset exceptions (more on that below).

In my experience with Kafka 0.7.x, removing the log files and restarting the broker could lead to invalid offset exceptions for certain consumers. This would happen because the broker restarts the offsets at zero (in the absence of any existing log files), and a consumer that was previously consuming from the topic would reconnect to request a specific [once valid] offset. If this offset happens to fall outside the bounds of the new topic logs, then no harm and the consumer resumes at either the beginning or the end. But, if the offset falls within the bounds of the new topic logs, the broker attempts to fetch the message set but fails because the offset doesn't align to an actual message.

This could be mitigated by also clearing the consumer offsets in zookeeper for that topic. But if you don't need a virgin topic and just want to remove the existing contents, then simply 'touch'-ing a few topic logs is far easier and more reliable, than stopping brokers, deleting topic logs, and clearing certain zookeeper nodes.