install zookeeper

获取ZooKeeper安装包
```
下载地址：http://apache.dataguru.cn/zookeeper

选择一个稳定版本进行下载，我这里下载的是zookeeper-3.4.6版本。
wget http://mirrors.sonic.net/apache/zookeeper/zookeeper-3.4.6/zookeeper-3.4.6.tar.gz 
```
ZooKeeper伪分布式集群安装

伪分布式集群：在一台Server中，启动多个ZooKeeper的实例。

上传并解压安装包
tar -zxvf zookeeper-3.4.6.tar.gz 

创建实例配置文件

cd zookeeper-3.4.6/conf
cp zoo_sample.cfg zoo1.cfg
cp zoo_sample.cfg zoo2.cfg
cp zoo_sample.cfg zoo3.cfg

修改配置文件

实例1的配置：
vi zoo1.cfg
 
tickTime=2000
initLimit=10
syncLimit=5
dataDir=/tmp/zookeeper/d_1
clientPort=2181
dataLogDir=/usr/zookeeper-3.4.6/logs_1
server.1=localhost:2887:3887
server.2=localhost:2888:3888
server.3=localhost:2889:3889
实例2的配置：
vi zoo2.cfg
 
tickTime=2000
initLimit=10
syncLimit=5
dataDir=/tmp/zookeeper/d_2
clientPort=2182
dataLogDir=/usr/zookeeper-3.4.6/logs_2
server.1=localhost:2887:3887
server.2=localhost:2888:3888
server.3=localhost:2889:3889
实例3的配置：
vi zoo3.cfg
 
tickTime=2000
initLimit=10
syncLimit=5
dataDir=/tmp/zookeeper/d_3
clientPort=2183
dataLogDir=/usr/zookeeper-3.4.6/logs_3
server.1=localhost:2887:3887
server.2=localhost:2888:3888
server.3=localhost:2889:3889
准备启动环境
mkdir /tmp/zookeeper/d_1
mkdir /tmp/zookeeper/d_2
mkdir /tmp/zookeeper/d_3
 
mkdir /usr/zookeeper-3.4.6/logs_1
mkdir /usr/zookeeper-3.4.6/logs_2
mkdir /usr/zookeeper-3.4.6/logs_3
 
echo "1" > /tmp/zookeeper/d_1/myid
echo "2" > /tmp/zookeeper/d_2/myid
echo "3" > /tmp/zookeeper/d_3/myid
启动集群
/usr/zookeeper-3.4.6/bin/zkServer.sh start zoo1.cfg
/usr/zookeeper-3.4.6/bin/zkServer.sh start zoo2.cfg
/usr/zookeeper-3.4.6/bin/zkServer.sh start zoo3.cfg
查看是否启动成功
jps
 
#看到类似下面的进程就表示3个实例均启动成功
13419 QuorumPeerMain
13460 QuorumPeerMain
13561 Jps
13392 QuorumPeerMain
 
#如果未成功启动，可以到zookeeper.out文件中查看启动失败的日志信息。
查看节点状态
[root@localhost ~]# /usr/zookeeper-3.4.6/bin/zkServer.sh status zoo1.cfg
JMX enabled by default
Using config: /usr/zookeeper-3.4.6/bin/../conf/zoo1.cfg
Mode: follower
[root@localhost ~]# /usr/zookeeper-3.4.6/bin/zkServer.sh status zoo2.cfg
JMX enabled by default
Using config: /usr/zookeeper-3.4.6/bin/../conf/zoo2.cfg
Mode: leader
[root@localhost ~]# /usr/zookeeper-3.4.6/bin/zkServer.sh status zoo3.cfg
JMX enabled by default
Using config: /usr/zookeeper-3.4.6/bin/../conf/zoo3.cfg
Mode: follower
 
#发现实例2为leader,实例1和实例3均为follower
    至此，一个ZK的伪分布式集群搭建完毕。