I'm testing Kafka in the new KRaft mode added in 2.8. I have a cluster of three Kafka nodes (all combined nodes), and one Kafka Connect node. After starting all components, I first stop the current controller of the Kafka cluster, then I stop the then controller of the Kafka cluster. At this point, only one Kafka node out of the original three and Connect is running.
When now restarting the two stopped Kafka nodes, CPU load on the Connect node and the two broker nodes goes up to 100% and remains at that level for an indefinite amount of time.