Zookeeper（二）------centos下zookeeper集群安装

短命女 2023-02-17 14:24 20阅读 0赞

## 一、下载 ##

https://mirrors.tuna.tsinghua.edu.cn/apache/zookeeper/

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI5OTE0ODM3_size_16_color_FFFFFF_t_70]  
![在这里插入图片描述][20200614192833459.png]

## 二、安装 ##

前提：安装jdk

解压缩 zookeeper 安装包

mkdir zookeeper
     cd zookeeper/
     tar -zxvf apache-zookeeper-3.6.1-bin.tar.gz

进入conf目录，cp生成一个zk能识别的配置文件名：zoo.cfg

cd apache-zookeeper-3.6.1-bin/conf/
     cp zoo_sample.cfg  zoo.cfg

修改配置文件zoo.cfg

vi zoo.cfg

# 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=/data/zookeeper
    # 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
    
    ## Metrics Providers
    #
    # https://prometheus.io Metrics Exporter
    #metricsProvider.className=org.apache.zookeeper.metrics.prometheus.PrometheusMetricsProvider
    #metricsProvider.httpPort=7000
    #metricsProvider.exportJvmInfo=true

## 三、启动Zookeeper ##

**3.1、启动节点**

默认会到同级目录conf中寻找zoo.cfg文件，所以默认不用加配置文件

./zkServer.sh start

![在这里插入图片描述][20200614193445470.png]  
如果启动报错，提示

: 找不到或无法加载主类 org.apache.zookeeper.server.quorum.QuorumPeerMain

zookeeper在3.5.5之后在下载的时候应该下载带bin的文件，而之前的普通的tar.gz的包里面是只是源码的包无法直接使用。

**3.2、查看节点状态**

./zkServer.sh status

![在这里插入图片描述][2020061419364167.png]

**3.2、关闭节点**

./zkServer.sh stop

![在这里插入图片描述][20200614193747628.png]

## 四、集群安装Zookeeper ##

Zookeeper节点部署越多，服务的可靠性越高，建议部署奇数个节点，因为zookeeper集群是以  
宕机个数过半才会让整个集群宕机的。

分别在三台服务器上安装Zookeeper服务，步骤按照上述即可

**4.1、修改配置文件zoo.cfg**

三台zoo.cfg文件内容一致

server.1=192.168.1.200:2888:3888
    server.2=192.168.1.201:2889:3889
    server.3=192.168.1.202:2890:3890

**4.2、添加myid文件**

集群模式下需要添加`myid`文件，保存路径为zoo.cfg文件下`dataDir=/data/zookeeper`路径下

myid文件内容为zoo.cfg文件中server.x，即对应（1，2，3），zookeeper会根据myid文件内容，判断那个是server（节点）

cd /data/zookeeper/

分别为1，2，3

vi myid
    1

vi myid
    2

vi myid
    3

**4.3、启动集群**

三台zk服务器分别执行启动命令

cd /usr/local/zookeeper/apache-zookeeper-3.6.1-bin/bin/
    ./zkServer.sh start

查看日志，发现启动失败

cd ..
    tail -f logs/zookeeper-root-server-192.168.1.200.out

2020-06-14 21:54:44,540 [myid:2] - WARN  [QuorumConnectionThread-[myid=2]-2:QuorumCnxManager@400] - Cannot open channel to 3 at election address /192.168.1.202:3890
    java.net.NoRouteToHostException: 没有到主机的路由 (Host unreachable)
    	at java.net.PlainSocketImpl.socketConnect(Native Method)
    	at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
    	at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
    	at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
    	at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
    	at java.net.Socket.connect(Socket.java:589)
    	at org.apache.zookeeper.server.quorum.QuorumCnxManager.initiateConnection(QuorumCnxManager.java:383)
    	at org.apache.zookeeper.server.quorum.QuorumCnxManager$QuorumConnectionReqThread.run(QuorumCnxManager.java:457)
    	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    	at java.lang.Thread.run(Thread.java:748)

**原因，防火墙未关闭导致**

systemctl stop firewalld.service #停止firewall
    
    systemctl disable firewalld.service #禁止firewall开机启动
    
    firewall-cmd --state #查看默认防火墙状态（关闭后显示notrunning，开启后显示running）

**查看节点状态**

./zkServer.sh status

200服务器

#从节点
    Mode: follower

201服务器

#从节点
    Mode: follower

202服务器

#主节点
    Mode: leader

## 五、zookeeper角色、状态介绍 ##

在zookeeper的集群中，节点具有3种角色、4种状态

角色：`leader,follower,observer`

状态：`leading,following,observing,looking`

leading：当前Server即为选举出来的leader。

following：已经选举出来，当前Server与之同步。

observing：的行为在大多数情况下与follower完全一致，但是他们不参加选举和投票，而仅仅接受(observing)选举和投票的结果。

looking：当前Server不知道leader是谁，正在搜寻。

## 六、设置开机自启 ##

cd /etc/rc.d/init.d/
    #创建zookeeper文件
    vi zookeeper

**编写脚本**

#!/bin/bash
    
    #chkconfig: 2345 80 90
    
    #description:zookeeper
     
    #processname:zookeeper
    export JAVA_HOME=/usr/java/jdk1.8.0_191
    case $1 in
              start)   su root /usr/local/zookeeper/apache-zookeeper-3.6.1-bin/bin/zkServer.sh start;;  
              stop)    su root /usr/local/zookeeper/apache-zookeeper-3.6.1-bin/bin/zkServer.sh stop;;    
              status)  su root /usr/local/zookeeper/apache-zookeeper-3.6.1-bin/bin/zkServer.sh status;;  
              restart) su root /usr/local/zookeeper/apache-zookeeper-3.6.1-bin/bin/zkServer.sh restart;;
         *)  echo "require start|stop|status|restart"  ;;  
    esac

#给文件添加权限
    chmod +x zookeeper
    #配置开机启动项
    chkconfig --add zookeeper
    #查看zk配置是否成功
    chkconfig --list

![在这里插入图片描述][20200614221930345.png]

#重启服务器测试是否成功
    reboot

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI5OTE0ODM3_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200614141259904.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI5OTE0ODM3,size_16,color_FFFFFF,t_70
[20200614192833459.png]: https://img-blog.csdnimg.cn/20200614192833459.png
[20200614193445470.png]: https://img-blog.csdnimg.cn/20200614193445470.png
[2020061419364167.png]: https://img-blog.csdnimg.cn/2020061419364167.png
[20200614193747628.png]: https://img-blog.csdnimg.cn/20200614193747628.png
[20200614221930345.png]: https://img-blog.csdnimg.cn/20200614221930345.png