在Docker中启动zookeeper模拟集群

这里我们将会使用docker-componse来启动3个zookeeper容器;

1.先下载好zookeeper的镜像docker pull zookeeper.

2.创建一个目录,在该目录下新建docker-componse.yml文件,内容如下:

version: '3.1'
services:
  zoo1:
    image: zookeeper
    restart: always
    hostname: zoo1
    ports:
      - 2181:2181
    environment:
      ZOO_MY_ID: 1
      ZOO_SERVERS: server.1=zoo1:2888:3888 server.2=zoo2:2888:3888 server.3=zoo3:2888:3888

  zoo2:
    image: zookeeper
    restart: always
    hostname: zoo2
    ports:
      - 2182:2181
    environment:
      ZOO_MY_ID: 2
      ZOO_SERVERS: server.1=zoo1:2888:3888 server.2=zoo2:2888:3888 server.3=zoo3:2888:3888

  zoo3:
    image: zookeeper
    restart: always
    hostname: zoo3
    ports:
      - 2183:2181
    environment:
      ZOO_MY_ID: 3
      ZOO_SERVERS: server.1=zoo1:2888:3888 server.2=zoo2:2888:3888 server.3=zoo3:2888:3888

其中:
2181端口号是客户端连接zookeeper集群监听的端口号,
3888是选举leader使用的端口号,
2888是集群内通讯使用,leader和follower之间数据同步使用的端口号,leader监听此端口号.

3.在该目录下启动命令行,运行docker-componse up -d启动这三个容器:

image.png

4.运行docker ps查看启动的容器:

image.png

5.以交互式的方式进入某个容器exec -it zookeeper_zoo3_1 /bin/bash,
并进入cd bin/目录,查看容器的状态./zkServer.sh status:

image.png

6.再进入cd /conf/目录,运行cat zoo.cfg查看zookpeeper容器的配置信息:

image.png
其中:
clientPort就是zookeeper服务端监听客户端的端口,
dataDir目录是数据存放的目录,并且在/data下的myid文件中定义了zookeeper服务的id编号, 也就是server.id