Kafka consumer should fail on "Bootstrap broker disconnected" - apache-kafka

When a Kafka consumer cannot access the bootstrap broker it indefinitely tries to reconnect with the following message:
WARN NetworkClient - [Consumer clientId=consumer-testGroup-1, groupId=testGroup] Connection to node -1 (localhost/127.0.0.1:9999) could not be established. Broker may not be available.
WARN NetworkClient - [Consumer clientId=consumer-testGroup-1, groupId=testGroup] Bootstrap broker localhost:9999 (id: -1 rack: null) disconnected
What I want is that the consumer throws an exception and aborts the execution. In the docs I couldn't find a property to limit the retries.
Is there a recommended way to implement this behaviour or a property I overlooked?
I am using the KafkaReceiver class from project reactor.

Related

Kafka producer does not signal that all brokers are unreachable

When all brokers/node of a cluster are unreachable, the error in the Kafka producer callback is a generic "Topic XXX not present in metadata after 60000 ms".
When I activate the DEBUG log level, I can see that all attempts to deliver the message to any node are failing:
DEBUG org.apache.kafka.clients.NetworkClient - Initialize connection to node node2.url:443 (id: 2 rack: null) for sending metadata request
DEBUG org.apache.kafka.clients.NetworkClient - Initiating connection to node node2.url:443 (id: 2 rack: null) using address node2.url:443/X.X.X.X:443
....
DEBUG org.apache.kafka.clients.NetworkClient - Disconnecting from node 2 due to socket connection setup timeout. The timeout value is 16024 ms.
DEBUG org.apache.kafka.clients.NetworkClient - Initialize connection to node node0.url:443 (id: 0 rack: null) for sending metadata request
DEBUG org.apache.kafka.clients.NetworkClient - Initiating connection to node node0.url:443 (id: 0 rack: null) using address node0.url:443/X.X.X.X:443
....
DEBUG org.apache.kafka.clients.NetworkClient - Disconnecting from node 0 due to socket connection setup timeout. The timeout value is 17408 ms.
and so on, until, after the deliver timeout, the send() Callback gets the error:
ERROR my.kafka.SenderClass - Topic XXX not present in metadata after 60000 ms.
Unlike bootstrap url, all nodes could be unreachable for example for wrong DNS entries or whatever.
How can the application understand that all nodes were not reachable? This is traced just as DEBUG info and is not avialable to the producer send() callback.
Such an error detail at application level would speed up troubleshoooting.
This error is usually signaled by standard webservice SOAP/REST interface.
The producer only cares about the cluster Controller for bootstrapping and the leaders of the partitions it needs to write to (one of those leaders could be the Controller). That being said, it doesn't need to know about "all" brokers.
How can the application understand that all nodes were not reachable?
If you set acks=1 or acks=all, then the callback should know at least one broker had the data written. If not, there was some error.
You can use an AdminClient outside of the Producer client to describe the topic(s) and fetch metadata about the leader partitions, then use standard TCP socket network requests to try and ping those advertised listeners from Java
FWIW, port 443 should ideally be reserved for HTTPS traffic, not Kafka. Kafka is not a REST/SOAP service.

Kafka client faced disconnected will reconnect again by again, anyway can disable it?

The client will reconnect again by itself again, anyway I can disable it?
Should I close Kafka client?
[2022-06-30 16:17:51,332] WARN [Consumer clientId=consumer-xxx, groupId=xxx] Bootstrap broker xxx:xxx (id: -1 rack: null) disconnected (org.apache.kafka.clients.NetworkClient)
[2022-06-30 16:17:52,387] WARN [Consumer clientId=consumer-pg-hudi001_5-1, groupId=pg-hudi001_5] Connection to node -1 (xxx) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
The consumer will constantly poll and periodically refresh its metadata about what brokers are available from the cluster Controller.
The only way to stop it from trying to connect is to close() the consumer, yes.

Auto restart Quarkus Microservice after broker unavailability

I have a very simple Quarkus microservice which uses smallrye reactive messaging (kafka). Sometimes my kafka broker goes down and I got the following logs :
2020-09-24 04:04:27,067 WARN [org.apa.kaf.cli.NetworkClient] (kafka-producer-network-thread | producer-1) [Producer clientId=producer-1] Bootstrap broker xxxxxxx.xxxx.xxx:2202 (id: -1 rack: null) disconnected 2020-09-24 04:04:27,083 WARN [org.apa.kaf.cli.NetworkClient] (kafka-producer-network-thread | producer-3) [Producer clientId=producer-3] Connection to node -1 (xxxxx.xxxx.xxxx.fr/XX.XX.XX.XXX:2202) could not be established. Broker may not be available.
After the broker has been restarted, I have to manually restart my microservice. Is it possible to add to capability to the microservice to reconsume the new incoming messages without any manual action?
Thank you!
If you are using KafkaProducer and Consumer API they automatically reconnect once the broker is up again.
Please ensure that in your application you do not throw an exception and kill the thread. If you keep the thread alive then it will reconnect. Catch all exceptions for Consumer thread to ensure it is not exiting due to a runtime exception.

Steps to delete data inside the Kafka Topic on Windows?

I am working on Spring Batch and Apache Kafka Integration. Before posting the question I went over web : Is there a way to delete all the data from a topic or delete the topic before every run? to find out better solution, but did not find out.
I am using Kafka version 2.11.
I want to delete all data under the topic without stopping either Zookeeper or Kafka. How can we do that ?
Below commands causes lot of issues in windows
C:\kafka_2.11-2.3.1\bin\windows>kafka-topics.bat --zookeeper localhost:2181 --delete --topic customers
Topic customers is marked for deletion.
Note: This will have no impact if delete.topic.enable is not set to true.
C:\kafka_2.11-2.3.1\bin\windows>kafka-topics.bat --zookeeper localhost:2181 --delete --topic test
C:\kafka_2.11-2.3.1\bin\windows>kafka-console-consumer.bat --bootstrap-server localhost:9092 --topic customers --from-beginning
[2020-04-21 10:25:02,812] WARN [Consumer clientId=consumer-1, groupId=console-consumer-65075] Connection to node -1 (localhost/127.0.0.1:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-21 10:25:04,886] WARN [Consumer clientId=consumer-1, groupId=console-consumer-65075] Connection to node -1 (localhost/127.0.0.1:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-21 10:25:06,996] WARN [Consumer clientId=consumer-1, groupId=console-consumer-65075] Connection to node -1 (localhost/127.0.0.1:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-21 10:25:09,267] WARN [Consumer clientId=consumer-1, groupId=console-consumer-65075] Connection to node -1 (localhost/127.0.0.1:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-21 10:25:11,744] WARN [Consumer clientId=consumer-1, groupId=console-consumer-65075] Connection to node -1 (localhost/127.0.0.1:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
Processed a total of 0 messages
Terminate batch job (Y/N)?
^C
C:\kafka_2.11-2.3.1\bin\windows>
I am using Kafka version 2.11.
There is no Kafka 2.11. Your command prompt says kafka_2.11-2.3.1: hence, you are using Kafka 2.3.1. The 2.11 part is the Scala version that was used during compilation.
Note: This will have no impact if delete.topic.enable is not set to true.
Did you check your broker configs if delete.topic.enable is set to true? If yes, you should be able to delete a topic without stopping ZK or the brokers. Note though, that deleting topics is async, i.e., when you command returns the topic is not deleted yet and it will take some time until the command is executed.

Continuous warnings in Kafka server.log

i started zookeeper and Kafka server in Linux machine. Both servers are started successfully. After that i created a "test" Topic. Everything working fine using console producer and console consumer. But when i try to send an event from a remote machine to Kafka server, it is failing. After some investigation i added the below configuration in server.properties
listeners=PLAINTEXT://0.0.0.0:9092
advertised.listeners=PLAINTEXT://xx.xx.xx.xx:9092
Then i got below continues Warning in Kafka logs
[2018-05-25 14:48:27,685] WARN [Controller id=0, targetBrokerId=0] Connection to node 0 could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
But exceptions in controller.log
[2018-05-25 14:48:27,583] WARN [RequestSendThread controllerId=0] Controller 0's connection to broker xx.xx.xx.xx:9092 (id: 0 rack: null) was unsuccessful (kafka.controller.Req
uestSendThread)
java.io.IOException: Connection to xx.xx.xx.xx:9092 (id: 0 rack: null) failed.
at org.apache.kafka.clients.NetworkClientUtils.awaitReady(NetworkClientUtils.java:70)
at kafka.controller.RequestSendThread.brokerReady(ControllerChannelManager.scala:271)
at kafka.controller.RequestSendThread.doWork(ControllerChannelManager.scala:225)
at kafka.utils.ShutdownableThread.run(ShutdownableThread.scala:82)
Please help to solve this issue
Thanks in advance