Zookeeper集群搭建（配置详解）

软件环境准备:

Linux服务器一台、三台、五台（2*n+1台）；Java jdk 1.7；zookeeper 3.4.6版；

软件安装：

解压jdk、zookeeper文件到指定目录，执行命令tar -zvxf xxxx.tar.gz -C /usr/local/program配置环境变量，vi /etc/profile #set enviroment export JAVA_HOME=/usr/local/program/jdk1.7.0_79 export ZK_HOME=/usr/local/program/zk/zookeeper-3.4.6 export PATH=$JAVA_HOME/bin:$ZK_HOME/bin:$PATH

java -version 命令测试是否成功配置jdk [root@localhost ~]# java -version java version "1.7.0_79" Java(TM) SE Runtime Environment (build 1.7.0_79-b15) Java HotSpot(TM) 64-Bit Server VM (build 24.79-b02, mixed mode)

配置zookeeper；首先建立两个文件夹mkdir /usr/local/program/zk/zkdata ，mkdir /usr/local/program/zk/zkdataLog 然后执行命令cd /usr/local/program/zk/zookeeper-3.4.6/conf/ 进入配置文件目录，拷贝一份配置文件cp zoo_sample.cfg zoo.cfg改名为zoo.cfg编辑配置文件修改配置（将端口改大的目的是为了防止冲突）： # 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=/usr/local/program/zk/zkdata dataLogDir=/usr/local/program/zk/zkdataLog # the port at which the clients will connect clientPort=12181 # 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=192.168.0.102:12888:13888 server.2=192.168.0.103:12888:13888 server.3=192.168.0.104:12888:13888

进入zkdata目录，执行命令echo “1” > myid创建myid文件并输入值为1依次在另外两台机器上执行同样的操作，myid的数值依次为2,3配置成功，执行命令zkServer.sh start分别启动三台机器执行命令zkServer.sh status查看对应的状态发现出现：zookeeper Error contacting service. It is probably not running错误执行命令：tail -f zookeeper.out 查看到错误记录： 2016-04-21 06:56:56,242 [myid:1] – WARN  [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:Follower@89] – Exception when following the leader java.net.NoRouteToHostException: No route to host at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339) at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200) at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) at java.net.Socket.connect(Socket.java:579) at org.apache.zookeeper.server.quorum.Learner.connectToLeader(Learner.java:225) at org.apache.zookeeper.server.quorum.Follower.followLeader(Follower.java:71) at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:786)

经验证：防火墙的问题，执行命令service iptables stop关闭防火墙（如要永久关闭防火墙执行命令：chkconfig iptables off）重启机器，执行命令zkServer.sh status 分别查看每台机器的状态为leader、follower、follower则表明启动成功

配置说明：

作用： leader：从客户端接收读写请求，响应读写请求，向slaver发送数据 slaver：从leader同步数据，当leader失败时，从新投票选举新的leader 配置详解： myid:位于快照目录，是用来标识本台机器在集群中的唯一标识 zoo.cfg: tickTime:是initLimit 和 syncLimit的时间单位（毫秒） initLimit:集群机器之间的同步时间，比如启动m1，s1在这个时间段内必须都起来 syncLimit：leader与follower之间的通信时间（心跳），超时则说明follower失败 #快照日志的存储路径 dataDir=/usr/local/program/zk/zkdata #zk事物日志存储目录 (如果不配置zkdataLog那么快照日志和事务日志都将写到dataDir中，严重影响性能) dataLogDir=/usr/local/program/zk/zkdataLog # the port at which the clients will connect #本台机器的端口，默认为2181 clientPort=12181 log4j.properties: 日志文件，zookeeper.out位置bin下面，可以更改 注意：需要定期清理事务日志文件，否则会造成性能下降（crontab） crontab -l查看当前用户定时任务 crontab -e编辑定时任务 (例：0 0 * * 0 sh /usr/local/program/zk/cleanup.sh) 另外2台机器执行同样的操作 #server.1标识本台机器，通过myid文件指定id=1;ip:机器之间通信端口（默认为2888）:leader选举端口（默认为3888） server.1=192.168.0.102:12888:13888