Does producers and consumers can write and read data, while we run kafka-reassign-partition tool to balance partition across brokers?

Question

While we are running kafka-reassign-partition tool to balance partitions across brokers. Does we have to stop producers and consumers to write and read data from kafka topic?

Answer 1

No we don't have to stop producers and consumers for partition re-assignment. Partition reassignment happens ,step by step , first the new assigned replicas will catch up with the leaders and once they become in-sync replicas ,then when preferred replica election happens ( either triggered manually or automatically triggered based on configuration) , then the depending on the leadership imbalance and new assignment, new leaders would be elected. Once new leaders are elected the producer and consumers would get an updated metadata, hence the producer and consumers continue to work as usual.