Zookeeper/Kafka: No Kafka brokers detected from Zookeeper cluster (Kafka runs fine)

Question

I have created a Kafka cluster with 4 nodes, a Zookeeper cluster with 3 nodes. Kafka is operating at v2.4.0 and Zookeeper at v3.5.6. Kafka cluster successfully starts and could successfully establish a connection with one of the nodes in the Zookeeper cluster (checked kafka logs), to that I can create/list topics, produce/consume messages off of this cluster when I use the --bootstrap-server option. But, upon using the --zookeeper option, things starts failing.

I also tried to list the kafka brokers using zkCli.sh utility that comes along with the standalone zookeeper installation, but, I got an empty list [] .

Command used:

./zkCli.sh -server localhost:2181
ls /brokers/ids

Although, upon using echo stat | nc localhost 2181 echo stat | nc localhost 2181 I can see a list of kafka brokers printed on the console.

I am a bit confused here, as to how my kafka cluster is operational even though queries directed to my zookeeper cluster fail & the fact that I could not list the active kafka brokers using the zkCli utility.

Any insights on this are highly appreciated.

Answer 1

Check the value of Zookeeper chroot path. If it is set, then the following command should be used:

./zkCli.sh -server localhost:2181/zookeeper_chroot_path
ls /brokers/ids

There should be no space between localhost:2181 and zookeeper_chroot_path

Answer 2

This problem arises often because of extra-spaces in the command line when using a zookeeper command-line handler. Just be noteful of the same.