一：kafka概述：

就一个消息中间件，当前官网叫做：分布式流平台a distributed streaming platform：
A streaming platform has three key capabilities:

1.Publish and subscribe to streams of records, similar to a message queue or enterprise messaging system.
2.Store streams of records in a fault-tolerant durable way.
3.Process streams of records as they occur.

Kafka is generally used for two broad classes of applications:

1.Building real-time streaming data pipelines that reliably get data between systems or applications
2.Building real-time streaming applications that transform or react to the streams of data

二：kafak对比Flume：

Flume is a distributed, reliable, and available system for efficiently collecting, aggregating, and moving large amounts of log data from many different sources to a centralized data store.

Flume： 只有1个进程：含Source Channel Sink
kafka : 有3个进程： producer broker cousumer
生成者 进程（存储） 消费者（sparkstreaming flik 结构化流)
编程语言为Scala
几个概率：主题Topic 区分不同的业务系统。落在磁盘上就是不同的文件夹。

三：kafka分布式部署：

3.1 分布式安装准备：

3.1.2:先安装Zookeeper CDH5.7.0

安装已经在前期HA时已安装好，具体情况如下：bin/zkServer.sh status

3.1.2:kafka 没有CDH5.7.0 ,在CDH中，kafka是独立分支。

kafka_2.11 - 0.10.0.1.tgz
scala2.11 版本
0.10.0.1 kafka版本