一、简介：
Zookeeper是一个分布式协调服务，提供的服务如下：
命名服务：类似于DNS，但仅对于节点
配置管理：服务配置信息的管理
集群管理：Dubbo使用Zookeeper实现服务治理
分布式锁：选举一个leader，这样某一时刻只有一个服务在干活，当leader出问题时释放锁，立即切到另一个服务
二、下载：
链接:https://pan.baidu.com/s/1ba8eYSxqnR1MdCxvQqWMTA 密码:ie5r
三、三种安装模式：
单机、真分布集群模式、伪分布集群模式
四、伪分布式集群搭建：
1、进入C:\zookeeper-3.3.6\conf目录，将zoo_sample.cfg拷贝成3份，分别为：zoo1.cfg、zoo2.cfg、zoo3.cfg
zoo1.cfg内容：
#心跳时间
tickTime=
#初始连接能容忍最多心跳次数
initLimit=
#leader与follower之间的通信时长
syncLimit=
#保存数据的目录
dataDir=C:/zookeeper/zk1
#zk监听端口号
clientPort=
#
server.=master::
server.=slave1::
server.=slave2::
zoo2.cfg内容：
# The number of milliseconds of each tick
tickTime=
# The number of ticks that the initial
# synchronization phase can take
initLimit=
# The number of ticks that can pass between
# sending a request and getting an acknowledgement
syncLimit=
# the directory where the snapshot is stored.
dataDir=C:/zookeeper/zk2/
# the port at which the clients will connect
clientPort= server.=master::
server.=slave1::
server.=slave2::
zoo3.cfg内容：
# The number of milliseconds of each tick
tickTime=
# The number of ticks that the initial
# synchronization phase can take
initLimit=
# The number of ticks that can pass between
# sending a request and getting an acknowledgement
syncLimit=
# the directory where the snapshot is stored.
dataDir=C:/zookeeper/zk3/
# the port at which the clients will connect
clientPort= server.=master::
server.=slave1::
server.=slave2::
2、hosts配置
127.0.0.1 master
127.0.0.1 slave1
127.0.0.1 slave2
3、zk保存数据的目录，zk1目录新建myid的文件,内容为1，zk2目录新建myid的文件，内容为2，以此类推
4、进入C:\zookeeper-3.3.6\bin目录，将zkServer.cmd拷贝成3份，分别为:zkServer-1.cmd、zkServer-2.cmd、zkServer-3.cmd
zkServer-1.cmd内容：
@echo off
REM Licensed to the Apache Software Foundation (ASF) under one or more
REM contributor license agreements. See the NOTICE file distributed with
REM this work for additional information regarding copyright ownership.
REM The ASF licenses this file to You under the Apache License, Version 2.0
REM (the "License"); you may not use this file except in compliance with
REM the License. You may obtain a copy of the License at
REM
REM http://www.apache.org/licenses/LICENSE-2.0
REM
REM Unless required by applicable law or agreed to in writing, software
REM distributed under the License is distributed on an "AS IS" BASIS,
REM WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
REM See the License for the specific language governing permissions and
REM limitations under the License. setlocal
call "%~dp0zkEnv.cmd" set ZOOMAIN=org.apache.zookeeper.server.quorum.QuorumPeerMain
set ZOOCFG=..\conf\zoo1.cfg echo on
java "-Dzookeeper.log.dir=%ZOO_LOG_DIR%" "-Dzookeeper.root.logger=%ZOO_LOG4J_PROP%" -cp "%CLASSPATH%" %ZOOMAIN% "%ZOOCFG%" %* endlocal
zkServer-2.cmd和zkServer-3.cmd只是set ZOOCFG指定的cfg文件不一样
5、启动zkServer-1.cmd、zkServer-2.cmd、zkServer-3.cmd