本篇文章主要介绍在CentOS 7环境下搭建zk和kafka集群，先默认你已经安装好zookeeper和kafkaf；我的zookeeper版本是3.4.13，kafka版本是2.11-2.1.1。

Zookeeper集群搭建

1. 先复制一份zoo_sample.cfg改名为zoo.cfg，在底部添加各节点信息:

   在最后添加（这里server.x中的x是一个数字，与myid文件中的id是一致的）：

   # The number of milliseconds of each tick
   tickTime=2000
   # The number of ticks that the initial 
   # synchronization phase can take
   initLimit=10
   # The number of ticks that can pass between 
   # sending a request and getting an acknowledgement
   syncLimit=5
   # the directory where the snapshot is stored.
   # do not use /tmp for storage, /tmp here is just 
   # example sakes.
   dataDir=/opt/zookeeper/data/
   dataLogDir=/opt/zookeeper/logs/
   # the port at which the clients will connect
   clientPort=2181
   # the maximum number of client connections.
   # increase this if you need to handle more clients
   #maxClientCnxns=60
   #
   # Be sure to read the maintenance section of the 
   # administrator guide before turning on autopurge.
   #
   # http://zookeeper.apache.org/doc/current/zookeeperAdmin.html#sc_maintenance
   #
   # The number of snapshots to retain in dataDir
   #autopurge.snapRetainCount=3
   # Purge task interval in hours
   # Set to "0" to disable auto purge feature
   #autopurge.purgeInterval=1
   
   server.1=192.168.1.92:2888:3888
   server.2=192.168.1.93:2888:3888
   server.3=192.168.1.94:2888:3888
   
   

   然后在配置文件中dataDir的目录下新建myid文件，内容和代表本机器server后的数字一样。

   zookeeper启动会占用三个端口，分别的作用是:

   2181：对cline端提供服务
   
   3888：选举leader使用
   
   2888：集群内机器通讯使用（Leader监听此端口）
   

2. 创建上面配置的日志目录

   dataDir=/opt/zookeeper/data/
   dataLogDir=/opt/zookeeper/logs/
   

   别忘了在dataDir目录下创建myid文件。

3. 分别启动三台服务器

   zkServer.sh start
   

   查看集群状态

   zkServer.sh status
   

   如果显示内容如下，代表集群搭建成功。

   ZooKeeper JMX enabled by default
   Using config: /opt/zookeeper/bin/../conf/zoo.cfg
   Mode: follower
   

Kafka搭建集群

1. 进入config目录，修改server.properties

   先修改broker.id=1 (其他服务器2/3)，然后修改zookeeper.connect=192.168.1.92:2181,192.168.1.93:2181,192.168.1.94:2181指向zk集群地址。

   # Licensed to the Apache Software Foundation (ASF) under one or more
   # contributor license agreements.  See the NOTICE file distributed with
   # this work for additional information regarding copyright ownership.
   # The ASF licenses this file to You under the Apache License, Version 2.0
   # (the "License"); you may not use this file except in compliance with
   # the License.  You may obtain a copy of the License at
   #
   #    http://www.apache.org/licenses/LICENSE-2.0
   #
   # Unless required by applicable law or agreed to in writing, software
   # distributed under the License is distributed on an "AS IS" BASIS,
   # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   # See the License for the specific language governing permissions and
   # limitations under the License.
   
   # see kafka.server.KafkaConfig for additional details and defaults
   
   ############################# Server Basics #############################
   
   # The id of the broker. This must be set to a unique integer for each broker.
   # 每一个broker在集群中的唯一标示，要求是正数。在改变IP地址，不改变broker.id的话不会影响consumers
   broker.id=1
   
   ############################# Socket Server Settings #############################
   
   # The address the socket server listens on. It will get the value returned from 
   # java.net.InetAddress.getCanonicalHostName() if not configured.
   #   FORMAT:
   #     listeners = listener_name://host_name:port
   #   EXAMPLE:
   #     listeners = PLAINTEXT://your.host.name:9092
   # 提供给客户端响应的地址和端口
   listeners=PLAINTEXT://192.168.1.92:9092
   
   # Hostname and port the broker will advertise to producers and consumers. If not set, 
   # it uses the value for "listeners" if configured.  Otherwise, it will use the value
   # returned from java.net.InetAddress.getCanonicalHostName().
   #advertised.listeners=PLAINTEXT://your.host.name:9092
   
   # Maps listener names to security protocols, the default is for them to be the same. See the config documentation for more details
   #listener.security.protocol.map=PLAINTEXT:PLAINTEXT,SSL:SSL,SASL_PLAINTEXT:SASL_PLAINTEXT,SASL_SSL:SASL_SSL
   
   # The number of threads that the server uses for receiving requests from the network and sending responses to the network
   # broker 处理消息的最大线程数，一般情况下不需要去修改
   num.network.threads=3
   
   # The number of threads that the server uses for processing requests, which may include disk I/O
   # broker处理磁盘IO的线程数 ，数值应该大于你的硬盘数
   num.io.threads=8
   
   # The send buffer (SO_SNDBUF) used by the socket server
   socket.send.buffer.bytes=102400
   
   # The receive buffer (SO_RCVBUF) used by the socket server
   # socket的发送缓冲区，socket的调优参数SO_SNDBUFF
   socket.receive.buffer.bytes=102400
   
   # The maximum size of a request that the socket server will accept (protection against OOM)
   # socket请求的最大数值，防止serverOOM，message.max.bytes必然要小于socket.request.max.bytes，会被topic创建时的指定参数覆盖
   socket.request.max.bytes=104857600
   
   
   ############################# Log Basics #############################
   
   # A comma separated list of directories under which to store log files
   # kafka数据的存放地址，多个地址的话用逗号分割/opt/kafka/logs，/opt/kafka/logs-2
   log.dirs=/opt/kafka/logs
   
   # The default number of log partitions per topic. More partitions allow greater
   # parallelism for consumption, but this will also result in more files across
   # the brokers.
   # 每个topic的分区个数，若是在topic创建时候没有指定的话会被topic创建时的指定参数覆盖
   num.partitions=1
   
   # The number of threads per data directory to be used for log recovery at startup and flushing at shutdown.
   # This value is recommended to be increased for installations with data dirs located in RAID array.
   # 我们知道segment文件默认会被保留7天的时间，超时的话就会被清理，那么清理这件事情就需要有一些线程来做。这里就是用来设置恢复和清理data下数据的线程数量
   num.recovery.threads.per.data.dir=1
   
   ############################# Internal Topic Settings  #############################
   # The replication factor for the group metadata internal topics "__consumer_offsets" and "__transaction_state"
   # For anything other than development testing, a value greater than 1 is recommended for to ensure availability such as 3.
   offsets.topic.replication.factor=1
   transaction.state.log.replication.factor=1
   transaction.state.log.min.isr=1
   
   ############################# Log Flush Policy #############################
   
   # Messages are immediately written to the filesystem but by default we only fsync() to sync
   # the OS cache lazily. The following configurations control the flush of data to disk.
   # There are a few important trade-offs here:
   #    1. Durability: Unflushed data may be lost if you are not using replication.
   #    2. Latency: Very large flush intervals may lead to latency spikes when the flush does occur as there will be a lot of data to flush.
   #    3. Throughput: The flush is generally the most expensive operation, and a small flush interval may lead to excessive seeks.
   # The settings below allow one to configure the flush policy to flush data after a period of time or
   # every N messages (or both). This can be done globally and overridden on a per-topic basis.
   
   # The number of messages to accept before forcing a flush of data to disk
   #log.flush.interval.messages=10000
   
   # The maximum amount of time a message can sit in a log before we force a flush
   #log.flush.interval.ms=1000
   
   ############################# Log Retention Policy #############################
   
   # The following configurations control the disposal of log segments. The policy can
   # be set to delete segments after a period of time, or after a given size has accumulated.
   # A segment will be deleted whenever *either* of these criteria are met. Deletion always happens
   # from the end of the log.
   
   # The minimum age of a log file to be eligible for deletion due to age
   # segment文件保留的最长时间，默认保留7天（168小时），超时将被删除，也就是说7天之前的数据将被清理掉。
   log.retention.hours=168
   
   # A size-based retention policy for logs. Segments are pruned from the log unless the remaining
   # segments drop below log.retention.bytes. Functions independently of log.retention.hours.
   #log.retention.bytes=1073741824
   
   # The maximum size of a log segment file. When this size is reached a new log segment will be created.
   # 日志文件中每个segment的大小，默认为1G
   log.segment.bytes=1073741824
   
   # The interval at which log segments are checked to see if they can be deleted according
   # to the retention policies
   #上面的参数设置了每一个segment文件的大小是1G，那么就需要有一个东西去定期检查segment文件有没有达到1G，多长时间去检查一次，就需要设置一个周期性检查文件大小的时间（单位是毫秒）。
   log.retention.check.interval.ms=300000
   
   ############################# Zookeeper #############################
   
   # Zookeeper connection string (see zookeeper docs for details).
   # This is a comma separated host:port pairs, each corresponding to a zk
   # server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002".
   # You can also append an optional chroot string to the urls to specify the
   # root directory for all kafka znodes.
   # 消费者集群通过连接Zookeeper来找到broker。zookeeper连接服务器地址
   zookeeper.connect=192.168.1.92:2181,192.168.1.93:2181,192.168.1.94:2181
   
   # Timeout in ms for connecting to zookeeper
   zookeeper.connection.timeout.ms=6000
   
   
   ############################# Group Coordinator Settings #############################
   
   # The following configuration specifies the time, in milliseconds, that the GroupCoordinator will delay the initial consumer rebalance.
   # The rebalance will be further delayed by the value of group.initial.rebalance.delay.ms as new members join the group, up to a maximum of max.poll.interval.ms.
   # The default value for this is 3 seconds.
   # We override this to 0 here as it makes for a better out-of-the-box experience for development and testing.
   # However, in production environments the default value of 3 seconds is more suitable as this will help to avoid unnecessary, and potentially expensive, rebalances during application startup.
   group.initial.rebalance.delay.ms=0
   

2. 分别启动三台kafka

   常规模式启动kafka

   kafka-server-start.sh config/server.properties
   

   进程守护模式启动kafka

   kafka-server-start.sh /opt/kafka/config/server.properties 1>/dev/null 2>&1 &
   

   停止命令

   kafka-server-stop.sh
   

   启动成功后，连接zk查看节点ids信息

   zkCli.sh -server 127.0.0.1:2181   连接zookeeper
   

   查看ids节点信息

   ls /brokers/ids
   

   如下所示代表成功

   [zk: 127.0.0.1:2181(CONNECTED) 0] ls /brokers/ids
   [1, 2, 3]
   

3. 命令测试

   查看topic

   kafka-topics.sh -list -zookeeper 192.168.1.92:2181,192.168.1.93:2181,192.168.1.94:2181
   

   创建topic

   kafka-topics.sh --create --zookeeper 192.168.1.92:2181,192.168.1.93:2181,192.168.1.94:2181 --replication-factor 3 --partitions 3 --topic test (rf参数副本数，par参数分区数，test是topic的名称)
   

   node1开启生产者

   kafka-console-producer.sh --broker-list 192.168.163.130:9092,192.168.163.131:9092,192.168.163.132:9092 --topic test
   

   node2和node3分别开启消费者

   kafka-console-consumer.sh --bootstrap-server 192.168.1.92:9092,192.168.1.93:9092,192.168.1.94:9092 --topic test --from-beginning