Error when setting kafka configs - apache-kafka

I want to configure SASL/SCRAM in Kafka. I found this resource[1](Slide 52 Create SCRAM Users) in slide share and when creating users, I get the following error.
Error while executing config command requirement failed: Invalid
entity config: all configs to be added must be in the format
"key=val".
java.lang.IllegalArgumentException: requirement failed: Invalid entity config: all configs to be added must be in the format "key=val".
at scala.Predef$.require(Predef.scala:233)
at kafka.admin.ConfigCommand$.parseConfigsToBeAdded(ConfigCommand.scala:128)
at kafka.admin.ConfigCommand$.alterConfig(ConfigCommand.scala:78)
at kafka.admin.ConfigCommand$.main(ConfigCommand.scala:65)
at kafka.admin.ConfigCommand.main(ConfigCommand.scala)
Here is the configuration that I run.
#!/usr/bin/env bash
SCRAM_CONFIG='SCRAM-SHA-256=[iterations=8192,password=kafka123]'
SCRAM_CONFIG="$SCRAM_CONFIG,SCRAM-SHA-512=[password=kafka123]"
./kafka-configs.sh --alter --add-config "$SCRAM_CONFIG" --entity-type users --entity-name stocks_consumer --zookeeper localhost:2181 \
./kafka-configs.sh --alter --add-config "$SCRAM_CONFIG" --entity-type users --entity-name stocks_producer --zookeeper localhost:2181 \
./kafka-configs.sh --alter --add-config "$SCRAM_CONFIG" --entity-type users --entity-name admin --zookeeper localhost:2181 \
I could not found any solution for this, so appreciate if I could get a hint to get this working.
EDIT: I'm using Kafka version 2.10.0.10.1.0
Thanks
[1] https://www.slideshare.net/JeanPaulAzar1/kafka-tutorial-kafka-security

I was able to solve the problem.
The support for SASL/SCRAM has been added in the kafka version 0.11 [1]
I did the same in the above version and it worked properly.
Thanks.
[1] https://archive.apache.org/dist/kafka/0.10.2.0/RELEASE_NOTES.html

Related

Error : Only quota configs can be added for 'clients' using --bootstrap-server. Unexpected config names: Set('producer_byte_rate)

I am trying to set Producer and Consumer quotas in Kafka. I have started zookeeper and kafka server and am trying to change Kafka config
`bin\windows\kafka-configs.bat --bootstrap-server localhost:9092 --alter --add-config 'producer_byte_rate=1024,consumer_byte_rate=2048,request_percentage=200' --entity-type clients --entity-default`
It shows me :
Only quota configs can be added for 'clients' using --bootstrap-server. Unexpected config names: Set('producer_byte_rate)
using the binaries of Kafka for Windows - you need to use without the " ' "
bin\windows\kafka-configs.bat --bootstrap-server localhost:9092 --alter --add-config producer_byte_rate=1024,consumer_byte_rate=2048,request_percentage=200 --entity-type clients --entity-default
Completed updating default config for clients in the cluster.
or using with " "
kafka-configs.bat --bootstrap-server localhost:9092 --alter --add-config "producer_byte_rate=1024,consumer_byte_rate=2048,request_percentage=200" --entity-type clients --entity-default
Completed updating default config for clients in the cluster.

How to set cleanup.policy 'delete' AND 'compact' for a Kafka topic?

The description of the Kafka topic cleanup.policy configuration is
A string that is either "delete" or "compact" or both. [...]
I wonder how to set both values. I am not able to get it work. A try to change a configuration this way has not the desired effect:
c:\Progs\kafka_2.12-2.2.0\bin\windows>kafka-configs.bat --zookeeper <...> --entity-type topics --entity-name MyTopic --alter --add-config cleanup.policy=[delete, compact]
Completed Updating config for entity: topic 'MyTopic'.
c:\Progs\kafka_2.12-2.2.0\bin\windows>kafka-configs.bat --zookeeper <...> --entity-type topics --entity-name MyTopic --describe
Configs for topic 'MyTopic' are cleanup.policy=delete,segment.ms=300000,retention.ms=86400000
And this way does not work either:
c:\Progs\kafka_2.12-2.2.0\bin\windows>kafka-configs.bat --zookeeper <...> --entity-type topics --entity-name MyTopic --alter --add-config "cleanup.policy=delete compact"
Error while executing config command with args '--zookeeper <...> --entity-type topics --entity-name MyTopic --alter --add-config cleanup.policy=delete compact'
org.apache.kafka.common.config.ConfigException: Invalid value delete compact for configuration cleanup.policy: String must be one of: compact, delete
at org.apache.kafka.common.config.ConfigDef$ValidString.ensureValid(ConfigDef.java:931)
at org.apache.kafka.common.config.ConfigDef$ValidList.ensureValid(ConfigDef.java:907)
at org.apache.kafka.common.config.ConfigDef.parseValue(ConfigDef.java:480)
at org.apache.kafka.common.config.ConfigDef.parse(ConfigDef.java:464)
at kafka.log.LogConfig$.validate(LogConfig.scala:305)
at kafka.zk.AdminZkClient.validateTopicConfig(AdminZkClient.scala:319)
at kafka.zk.AdminZkClient.changeTopicConfig(AdminZkClient.scala:331)
at kafka.zk.AdminZkClient.changeConfigs(AdminZkClient.scala:268)
at kafka.admin.ConfigCommand$.alterConfig(ConfigCommand.scala:152)
at kafka.admin.ConfigCommand$.processCommandWithZk(ConfigCommand.scala:103)
at kafka.admin.ConfigCommand$.main(ConfigCommand.scala:80)
at kafka.admin.ConfigCommand.main(ConfigCommand.scala)
It should be cleanup.policy=[delete,compact] instead of cleanup.policy=[delete, compact]. No blank space follows the comma.
I made it work with
--add-config cleanup.policy='[compact,delete]'

how to get the producer client id or entity-name list in Kafka

I'd like to set quota for each Producer and Consumer. For example the following command to set the quotas:
./kafka-configs.sh --zookeeper localhost:2181
--alter --add-config 'producer_byte_rate=1048,consumer_byte_rate=2097'
--entity-name test-client --entity-type clients
my question is that: how can I get the entity-name? because right now there are hundreds of producers and consumers are using Kafka, but I don't know their ids/names.
You can use --entity-default to apply the quota to all client-ids. This is mentioned in the Setting quotas section in the documentation:
It is possible to set default quotas for each (user, client-id), user
or client-id group by specifying --entity-default option instead of
--entity-name.
Your command would be:
./kafka-configs.sh --zookeeper localhost:2181
--alter --add-config 'producer_byte_rate=1048,consumer_byte_rate=2097'
--entity-default --entity-type clients

changing kafka retention period during runtime

With Kafka 0.8.1.1, how do I change the log retention time while it's running? The documentation says the property is log.retention.hours, but trying to change it using kafka-topics.sh returns this error
$ bin/kafka-topics.sh --zookeeper zk.yoursite.com --alter --topic as-access --config topic.log.retention.hours=24
Error while executing topic command requirement failed: Unknown configuration "topic.log.retention.hours".
java.lang.IllegalArgumentException: requirement failed: Unknown configuration "topic.log.retention.hours".
at scala.Predef$.require(Predef.scala:145)
at kafka.log.LogConfig$$anonfun$validateNames$1.apply(LogConfig.scala:138)
at kafka.log.LogConfig$$anonfun$validateNames$1.apply(LogConfig.scala:137)
at scala.collection.Iterator$class.foreach(Iterator.scala:631)
at scala.collection.JavaConversions$JEnumerationWrapper.foreach(JavaConversions.scala:479)
at kafka.log.LogConfig$.validateNames(LogConfig.scala:137)
at kafka.log.LogConfig$.validate(LogConfig.scala:145)
at kafka.admin.TopicCommand$.parseTopicConfigsToBeAdded(TopicCommand.scala:171)
at kafka.admin.TopicCommand$$anonfun$alterTopic$1.apply(TopicCommand.scala:95)
at kafka.admin.TopicCommand$$anonfun$alterTopic$1.apply(TopicCommand.scala:93)
at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:57)
at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:43)
at kafka.admin.TopicCommand$.alterTopic(TopicCommand.scala:93)
at kafka.admin.TopicCommand$.main(TopicCommand.scala:52)
at kafka.admin.TopicCommand.main(TopicCommand.scala)
log.retention.hours is a property of a broker which is used as a default value when a topic is created. When you change configurations of currently running topic using kafka-topics.sh, you should specify a topic-level property.
A topic-level property for log retention time is retention.ms.
From Topic-level configuration in Kafka 0.8.1 documentation:
Property: retention.ms
Default: 7 days
Server Default Property: log.retention.minutes
Description: This configuration controls the maximum time we will retain a log before we will discard old log segments to free up space if we are using the "delete" retention policy. This represents an SLA on how soon consumers must read their data.
So the correct command depends on the version. Up to 0.8.2 (although docs still show its use up to 0.10.1) use kafka-topics.sh --alter and after 0.10.2 (or perhaps from 0.9.0 going forward) use kafka-configs.sh --alter
$ bin/kafka-topics.sh --zookeeper zk.yoursite.com --alter --topic as-access --config retention.ms=86400000
You can check whether the configuration is properly applied with the following command.
$ bin/kafka-topics.sh --describe --zookeeper zk.yoursite.com --topic as-access
Then you will see something like below.
Topic:as-access PartitionCount:3 ReplicationFactor:3 Configs:retention.ms=86400000
The following is the right way to alter topic config as of Kafka 0.10.2.0:
bin/kafka-configs.sh --zookeeper <zk_host> --alter --entity-type topics --entity-name test_topic --add-config retention.ms=86400000
Topic config alter operations have been deprecated for bin/kafka-topics.sh.
WARNING: Altering topic configuration from this script has been deprecated and may be removed in future releases.
Going forward, please use kafka-configs.sh for this functionality`
The correct config key is retention.ms
$ bin/kafka-topics.sh --zookeeper zk.prod.yoursite.com --alter --topic as-access --config retention.ms=86400000
Updated config for topic "my-topic".
I tested and used this command in kafka confluent V4.0.0 and apache kafka V 1.0.0 and 1.0.1
/opt/kafka/confluent-4.0.0/bin/kafka-configs --zookeeper XX.XX.XX.XX:2181 --entity-type topics --entity-name test --alter --add-config retention.ms=55000
test is the topic name.
I think it works well in other versions too

Is there a way to purge the topic in Kafka?

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.
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.
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
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
Here are the steps to follow to delete a topic named MyTopic:
Describe the topic, and take note of the broker ids
Stop the Apache Kafka daemon for each broker ID listed.
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
Delete the topic metadata: zkCli.sh then rmr /brokers/MyTopic
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.
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
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
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
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
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
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.
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.
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.
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:
No need to bring down brokers, it's a runtime operation.
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.
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.
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
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
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
Another, rather manual, approach for purging a topic is:
in the brokers:
stop kafka broker
sudo service kafka stop
delete all partition log files (should be done on all brokers)
sudo rm -R /kafka-storage/kafka-logs/<some_topic_name>-*
in zookeeper:
run zookeeper command line interface
sudo /usr/lib/zookeeper/bin/zkCli.sh
use zkCli to remove the topic metadata
rmr /brokers/topic/<some_topic_name>
in the brokers again:
restart broker service
sudo service kafka start
./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
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;
}
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();
}
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
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.
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.
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
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.