"unreasonable length" when running kafka-topics command

Question

I installed Kafka 2.4.0 and am seeing odd behavior when I run the kafka-topics.sh command.

I can start zookeeper and kafka with no issues, and when I run this

kafka-topics.sh --bootstrap-server 127.0.0.1:2181 --version

I get this: 2.4.0 (Commit:77a89fcf8d7fa018)

So far so good. But if I try to list all the topics:

kafka-topics.sh --bootstrap-server 127.0.0.1:2181 --list

the command just hangs and I see the zookeeper console spews this message repeatedly:

WARN Exception causing close of session 0x0: Unreasonable length = 308375649

At first I thought this may be a clash with Confluent 5.3.2, which I also had installed, but I removed that. I uninstalled Kafka, and re-installed. No joy.

Answer 1

kafka-topics.sh --bootstrap-server 127.0.0.1:2181 --list

The problem is that you are using zookeeper address as a bootstrap-server address. It shoud be like this:

kafka-topics.sh --bootstrap-server 127.0.0.1:9092 --list

Alternatively you can also use zookeeper address too with --zookeeper parameter like this:

kafka-topics.sh --zookeeper 127.0.0.1:2181 --list

P.S: Prior to Kafka version 2.2 zookeeper is the only valid option in topics.sh, but after that both bootstrap-server and zookeeper are valid options. You can check this for more information.