When a source connector configured with many tasks and to use the new topic creation feature is run, it is possible that multiple tasks will attempt to write to the same topic, will see that the topic does not exist, and then race to create the topic. The topic is only created once, but some tasks might fail with:
The reason appears to be that the WorkerSourceTask throws an exception if the topic creation failed, and does not account for the fact that the topic may have been created between the time the WorkerSourceTask lists existing topics and tries to create the topic.
This is only an issue when using topic creation settings in the source connector configuration, and when running multiple tasks that write to the same topic.
The workaround is to create the topics manually before starting the connector, or to simply restart the failed tasks using the REST API.