查看现在副本分配情况

../bin/kafka-topics.sh --zookeeper 127.0.0.1:2181 --describe  --topic test1
Topic:test1 PartitionCount:3 ReplicationFactor:2 Configs:
Topic: test1 Partition: 0 Leader: 2 Replicas: 2,4 Isr: 2,4
Topic: test1 Partition: 1 Leader: 3 Replicas: 3,5 Isr: 3,5
Topic: test1 Partition: 2 Leader: 4 Replicas: 4,1 Isr: 4,1

topic 分区扩容

./kafka-topics.sh --zookeeper 127.0.0.1:2181 -alter --partitions 4 --topic test1