Launching multiple Kafka brokers fails

Question

While trying to launch multiple Kafka brokers with different brokerId's. One being the default server.properties and the other being serverTest.properties with 2 lines changed, those being broker.id=1 and listeners=PLAINTEXT://localhost:6000. The rest is the same default setting. I first start zookeeper, then the default kafka server.properties then while launching serverTest.properties I get the following exception: kafka.common.InconsistentBrokerIdException: Configured brokerId 1 doesn't match stored brokerId 0 in meta.properties. My understanding is that the following above should actually launch multiple nodes, as I've seen others do in tutorials. I'm using Kafka 9.0.

Answer 1

Edit config/serverTest.properties and replace the existing config values as follows:

broker.id=2
port=9093
log.dir=/tmp/kafka-logs-2

If you want a third broker:

cp config/server.properties config/server3.properties

Edit config/server3.properties and replace the existing config values as follows:

broker.id=3
port=9094
log.dir=/tmp/kafka-logs-3

if you run on different machines you must change

advertised.host.name=192.168.x.x

else if you run in the same vmware machine, for example you should only change the port and log.dir as described above

Answer 2

And, speaking from experience, don't forget to edit the broker.id entries in the kafka-logs-*/meta.properties files to match your changes (or delete the files and let kafka regenerate them).

Answer 3

This is old question, still this answer should help others. The problem is when you create new server.properties from existing server.properties, below line will get copied:

# A comma separated list of directories under which to store log files
log.dirs=/tmp/kafka-logs

So, even new broker tries to use the same log dir and hence it uses the meta.properties of kafka-logs which is created by broker 0 and has broker id as 0.

So, go to /tmp and delete all kafka-logs* files and then comment log.dirs=/tmp/kafka-logs and then add the lines as you have added :)

Answer 4

The answers are perfect but it took me a while to figure it out to get it work. I would like to share my mistake and hope others can avoid it.

I followed the official tutorial with kafka here:

https://kafka.apache.org/quickstart#quickstart_multibroker.

and make a file copy as suggested in the guide:

cp config/server.properties config/server-1.properties

I open the file using vim. I do a search for broker.id and replace with the following(mistake by assuming there is no existing listeners and log.dirs) as below

# config/server-1.properties:
broker.id=1
listeners=PLAINTEXT://:9093
log.dirs=/tmp/kafka-logs-1

I started a new broker with

 >  bin/kafka-server-start.sh config/server-1.properties

crashed!!!. This is how I debug:

I went /tmp and checked the dir kafka-logs-1 did not appear. I realized that there should be something wrong with my log.dir in config. I double checked it in the config/server-1.propeties. I found that there were two lines of log.dirs.

#copy from the tutorial
log.dirs=/tmp/kafka-logs-1


# default one
log.dirs=/tmp/kafka-logs

Of course the last one overridden the first one thus making the new broker point to the first broker with id=0.

After removing the last log.dirs and keep only one log.dirs ( log.dirs=/tmp/kafka-logs-1 ) works like a charm.

Answer 5

Make sure in your server.properties and serverTest.properties you have different log.dirs

If you had to make any log.dirs changes don't forget to remove previous folders stored on your PC

Answer 6

Make sure the log directories, broker id and ports are different for each node/broker.

Sample configuration (server.properties):

Broker 1

broker.id=1
listeners=PLAINTEXT://:9092
log.dirs=/tmp/kafka-1-logs

Broker 2

broker.id=2
listeners=PLAINTEXT://:9093
log.dirs=/tmp/kafka-2-logs

Broker 3

broker.id=3
listeners=PLAINTEXT://:9094
log.dirs=/tmp/kafka-3-logs

Hope this will help. Happy hacking!!