2. volatile 关键字-内存可见性

拼搏现实的明天。 2022-03-09 06:57 292阅读 0赞

### 一、安装准备 ###

*  **下载`Zookeeper`：[CentOS 7 下载 安装 Zookeeper][CentOS 7 _ _ Zookeeper]**
 *  **安装`JDK`：[CentOS 7 下载 安装 JDK][CentOS 7 _ _ JDK]**  
    ![在这里插入图片描述][2019092610062578.png]

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### 二、`Zookeeper`集群模式 ###

#### A、多台机器安装`Zookeeper` ####

![在这里插入图片描述][20190923230953978.png]  
![在这里插入图片描述][20190923230746529.png]  
![在这里插入图片描述][20190923230842971.png]

#### B、创建`data`、`log`存储目录 ####

mkdir -p /data/data/zookeeper/data
    mkdir -p /data/data/zookeeper/log

![在这里插入图片描述][20190923231226194.png]  
![在这里插入图片描述][20190923231258689.png]  
![在这里插入图片描述][20190923231327151.png]

#### C、新增`zoo.cfg`配置文件 ####

cd /data/opt/apache-zookeeper-3.5.5-bin
    cp ./conf/zoo_sample.cfg ./conf/zoo.cfg

*  **`192.168.31.241`：`/data/opt/apache-zookeeper-3.5.5-bin/conf/zoo.cfg`**
 *  **`192.168.31.79`：`/data/opt/apache-zookeeper-3.5.5-bin/conf/zoo.cfg`**
 *  **`192.168.31.112`：`/data/opt/apache-zookeeper-3.5.5-bin/conf/zoo.cfg`**

# 基本事件单元，单位毫秒。
    tickTime=2000
    
    initLimit=10
    syncLimit=5
    
    # 存储内存中数据库快照的位置，默认是/tmp/zookeeper
    dataDir=/data/data/zookeeper/data
    
    # 日志路径，也就是事务日志。
    dataLogDir=/data/data/zookeeper/log
    
    # 监听客户端连接的端口
    clientPort=2181
    
    server.1=192.168.31.241:2281:2381
    server.2=192.168.31.79:2281:2381
    server.3=192.168.31.112:2281:2381

#### D、新增`myid`文件 ####

**`myid`文件内容是当前服务器的编号。**

*  **`192.168.31.241`：**
    
        echo '1' > /data/data/zookeeper/data/myid
 *  **`192.168.31.79`：**
    
        echo '2' > /data/data/zookeeper/data/myid
 *  **`192.168.31.112`：**
    
        echo '3' > /data/data/zookeeper/data/myid

#### E、关闭防火墙或开放端口 ####

*  **[CentOS 7 关闭防火墙 启用 iptables][CentOS 7 _ _ iptables]**

#### E、启动`Zookeeper`集群 ####

*  **`192.168.31.241`：`/data/opt/apache-zookeeper-3.5.5-bin/bin/zkServer.sh start`**  
    ![在这里插入图片描述][20190923232653598.png]
 *  **`192.168.31.79`：`/data/opt/apache-zookeeper-3.5.5-bin/bin/zkServer.sh start`**  
    ![在这里插入图片描述][2019092323271763.png]
 *  **`192.168.31.112`：`/data/opt/apache-zookeeper-3.5.5-bin/bin/zkServer.sh start`**  
    ![在这里插入图片描述][20190923232734392.png]

#### F、查看`Zookeeper`集群状态 ####

*  **`192.168.31.241`：`/data/opt/apache-zookeeper-3.5.5-bin/bin/zkServer.sh status`**  
    ![在这里插入图片描述][20190923234056284.png]
 *  **`192.168.31.79`：`/data/opt/apache-zookeeper-3.5.5-bin/bin/zkServer.sh status`**  
    ![在这里插入图片描述][20190923234124996.png]
 *  **`192.168.31.112`：`/data/opt/apache-zookeeper-3.5.5-bin/bin/zkServer.sh status`**  
    ![在这里插入图片描述][20190923234152819.png]

#### G、测试`Zookeeper`集群 ####

# 连接 192.168.31.241 端口 2181 Zookeeper服务器
    /data/opt/apache-zookeeper-3.5.5-bin/bin/zkCli.sh -server 192.168.31.241:2181
    
    # 创建节点看是否同步
    create /data test

![在这里插入图片描述][20190923234756259.png]

# 连接 192.168.31.79 端口 2181 Zookeeper服务器
    /data/opt/apache-zookeeper-3.5.5-bin/bin/zkCli.sh -server 192.168.31.79:2181
    
    # 查看 data 节点
    ls /
    
    # 查看 data 节点数据
    get /data

![在这里插入图片描述][20190923234938223.png]

[CentOS 7 _ _ Zookeeper]: https://blog.csdn.net/yhj19920417/article/details/46969921
[CentOS 7 _ _ JDK]: https://blog.csdn.net/yhj19920417/article/details/46547181
[2019092610062578.png]: /images/20220309/8d19b4f1debb4183ba3b323f604317d7.png
[20190923230953978.png]: /images/20220309/80af988b1b4049609f6e868de7586f98.png
[20190923230746529.png]: /images/20220309/f5b9c2ed34b44f719e7451af33a80ed9.png
[20190923230842971.png]: /images/20220309/4fff25ba72484305a2827d007889e370.png
[20190923231226194.png]: /images/20220309/b2654d5f641745cfb4d3075a398898dc.png
[20190923231258689.png]: /images/20220309/2ec4c4b97bb24caf95823680e2fb211c.png
[20190923231327151.png]: /images/20220309/c841a9a8885e461db8ba529fe0002838.png
[CentOS 7 _ _ iptables]: https://blog.csdn.net/yhj19920417/article/details/83549726
[20190923232653598.png]: /images/20220309/d8cb432fc409424f9d58b3d338bda6e2.png
[2019092323271763.png]: /images/20220309/a0514b8f445648419f7414048204a3b4.png
[20190923232734392.png]: /images/20220309/6d28d36ca0e8489ebcf4e948a9ad608f.png
[20190923234056284.png]: /images/20220309/caf8b4889f774a03bbcba4c112aa55a0.png
[20190923234124996.png]: /images/20220309/b73b688d737f4dbebe2d32c786d8ec48.png
[20190923234152819.png]: /images/20220309/b08c2122f36049728de7e9d5170ba582.png
[20190923234756259.png]: /images/20220309/1de093811c434f1e9a2d152d91223b7c.png
[20190923234938223.png]: /images/20220309/4d2ba5e5a8ff42699dd6953d64ec2921.png