kakfa使用过程中、因部分程序bug或者某些原因，集群中只创建一个分区、或创建多个分区只用了一个分区。

一、环境

环境：集群
ip：192.168.174.44:6667 broker-id 0、192.168.174.55:6668 broker-id 1、192.168.174.99:6669 broker-id 2
topic： test1 单分区单副本、normal 3分区2副本、official 单分区单副本

二、测试过程

1.kafka工具创建测试、正常和实验三个topic

2.增加分区（区别）

测试：为test1增加为三个分区单副本(分区数不超过节点数)

[root@h5 bin]# ./kafka-topics.sh --zookeeper 192.168.174.55:2182  --topic normal  --describe
Topic:normal	PartitionCount:3	ReplicationFactor:2	Configs:
	Topic: normal	Partition: 0	Leader: 0	Replicas: 0,1	Isr: 0,1
	Topic: normal	Partition: 1	Leader: 1	Replicas: 1,2	Isr: 2,1
	Topic: normal	Partition: 2	Leader: 2	Replicas: 2,0	Isr: 2,0

[root@h5 bin]#./kafka-topics.sh --zookeeper 192.168.174.55:2182 --alter --topic test1 --partitions 3
Adding partitions succeeded!
[root@h5 bin]# ./kafka-topics.sh --zookeeper 192.168.174.55:2182  --topic test1  --describe           
Topic:test1	PartitionCount:3	ReplicationFactor:1	Configs:
	Topic: test1	Partition: 0	Leader: 1	Replicas: 1	Isr: 1
	Topic: test1	Partition: 1	Leader: 2	Replicas: 2	Isr: 2
	Topic: test1	Partition: 2	Leader: 0	Replicas: 0	Isr: 0

3. offical 增加分区，分配数据。

[root@h4 bin]#  ./kafka-topics.sh --zookeeper 192.168.174.44:2181  --alter --topic official --partitions 3
Adding partitions succeeded!

[root@h4 bin]# ./kafka-reassign-partitions.sh --zookeeper 192.168.174.44:2181 --broker-list "0,1,2" --topics-to-move-json-file topic-generate.json --generate
Current partition replica assignment
{"version":1,"partitions":[{"topic":"hrmwRawDatav2","partition":0,"replicas":[0],"log_dirs":["any"]},{"topic":"hrmwRawDatav2","partition":2,"replicas":[2],"log_dirs":["any"]},{"topic":"hrmwRawDatav2","partition":1,"replicas":[1],"log_dirs":["any"]}]}

Proposed partition reassignment configuration   ##建议的分区重新分配配置
{"version":1,"partitions":[{"topic":"hrmwRawDatav2","partition":1,"replicas":[0],"log_dirs":["any"]},{"topic":"hrmwRawDatav2","partition":0,"replicas":[2],"log_dirs":["any"]},{"topic":"hrmwRawDatav2","partition":2,"replicas":[1],"log_dirs":["any"]}]}

[root@h4 bin]# cat topic-generate.json 
{
  "topics": [
    {
      "topic": "hrmwRawDatav2"
    }
  ],
  "version": 1
}

#增加副本数，replicas[此为broker id]

[root@h4 bin]# ./kafka-reassign-partitions.sh  --zookeeper 192.168.174.44:2181  --reassignment-json-file topic-increase.json --execute
Current partition replica assignment

{"version":1,"partitions":[{"topic":"hrmwRawDatav2","partition":0,"replicas":[0],"log_dirs":["any"]},{"topic":"hrmwRawDatav2","partition":2,"replicas":[2],"log_dirs":["any"]},{"topic":"hrmwRawDatav2","partition":1,"replicas":[1],"log_dirs":["any"]}]}

Save this to use as the --reassignment-json-file option during rollback
Successfully started reassignment of partitions.

[root@h4 bin]# cat topic-increase.json 
{
	"version": 1,
	"partitions": [{
		"topic": "hrmwRawDatav2",
		"partition": 0,
		"replicas": [0,1]
	}, {
		"topic": "hrmwRawDatav2",
		"partition": 1,
		"replicas": [1,2]
	}, {
		"topic": "hrmwRawDatav2",
		"partition": 2,
		"replicas": [2,0]
	}]
}