Zookeepr分布式集群搭建

vim /etc/hosts

192.168.10.11 linux1
192.168.10.12 linux2
192.168.10.13 linux3

server.1=linux1:2888:3888
server.2=linux2:2888:3888
server.3=linux3:2888:3888

[hadoop@linux1 Data]$ vi myid

[hadoop@linux1 module]$ scp -r  apache-zookeeper-3.6.0/ hadoop@linux2:/opt/module/
[hadoop@linux1 module]$ scp -r  apache-zookeeper-3.6.0/ hadoop@linux3:/opt/module/

[hadoop@linux1 module]$ ssh linux2
Last login: Tue Mar 24 11:32:24 2020 from linux1
[hadoop@linux2 ~]$ echo 2 > /opt/module/apache-zookeeper-3.6.0/Data/myid 
[hadoop@linux2 ~]$ cat /opt/module/apache-zookeeper-3.6.0/Data/myid 
2
[hadoop@linux2 ~]$ exit
logout
Connection to linux2 closed.
[hadoop@linux1 module]$ 

[hadoop@linux1 module]$ ssh linux3
Last login: Mon Mar 23 14:15:50 2020
[hadoop@linux3 ~]$ echo 3 > /opt/module/apache-zookeeper-3.6.0/Data/myid 
[hadoop@linux3 ~]$ cat /opt/module/apache-zookeeper-3.6.0/Data/myid 
3
[hadoop@linux3 ~]$ exit
logout
Connection to linux3 closed.
[hadoop@linux1 module]$ 

[hadoop@linux1 apache-zookeeper-3.6.0]$ ./bin/zkServer.sh  start
ZooKeeper JMX enabled by default
Using config: /opt/module/apache-zookeeper-3.6.0/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
[hadoop@linux1 apache-zookeeper-3.6.0]$ ssh linux2
Last login: Tue Mar 24 11:33:58 2020 from linux1
[hadoop@linux2 ~]$ /opt/module/apache-zookeeper-3.6.0/bin/zkServer.sh start
ZooKeeper JMX enabled by default
Using config: /opt/module/apache-zookeeper-3.6.0/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
[hadoop@linux2 ~]$ exit
logout
Connection to linux2 closed.
[hadoop@linux1 apache-zookeeper-3.6.0]$ ssh linux 2
ssh: Could not resolve hostname linux: Name or service not known
[hadoop@linux1 apache-zookeeper-3.6.0]$ ssh linux3
Last login: Tue Mar 24 11:35:38 2020 from linux1
[hadoop@linux3 ~]$ /opt/module/apache-zookeeper-3.6.0/bin/zkServer.sh start
ZooKeeper JMX enabled by default
Using config: /opt/module/apache-zookeeper-3.6.0/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
[hadoop@linux3 ~]$ exit
logout
Connection to linux3 closed.
[hadoop@linux1 apache-zookeeper-3.6.0]$

export ZOOKEEPER_HOME=/opt/module/apache-zookeeper-3.6.0
export PATH=$PATH:$ZOOKEEPER_HOME/bin

tickTime：通信心跳数，Zookeeper 服务器心跳时间，单位毫秒

Zookeeper 使用的基本时间，服务器之间或客户端与服务器之间维持心跳的时间间隔，也就是每个 tickTime 时间就会发送一个心跳，时间单位为毫秒。

它用于心跳机制，并且设置最小的 session 超时时间为两倍心跳时间。(session 的最小超时时间是 2 *tickTime)

集群中的 follower 跟随者服务器 (F) 与 leader 领导者服务器 (L) 之间初始连接时能容忍的最多心跳数（tickTime 的数量），用它来限定集群中的 Zookeeper 服务器连接到 Leader 的时限。

投票选举新 leader 的初始化时间

Follower 在启动过程中，会从 Leader 同步所有最新数据，然后确定自己能够对外服务的起始状态。

Leader 允许 F 在 initLimit 时间内完成这个工作。

4）dataDir：数据文件目录 + 数据持久化路径

保存内存数据库快照信息的位置，如果没有其他说明，更新的事务日志也保存到数据库。

监听客户端连接的端口