1.下載zookeeper安裝包

linux的套路是，一般都會把安裝檔案放到/opt下 wget https://mirrors.tuna.tsinghua.edu.cn/apache/zookeeper/stable/zookeeper-3.4.12.tar.gz

2.配置zoo.cfg

解壓，mv重新命名一下 然後進到 /opt/zookeeper/conf 把zoo_sample.cfg重新命名為zoo.cfg 內容如下：

# The number of milliseconds of each tick
tickTime=2000
# The number of ticks that the initial
# synchronization phase can take
initLimit=10
# The number of ticks that can pass between
# sending a request and getting an acknowledgement
syncLimit=5
# the directory where the snapshot is stored.
# do not use /tmp for storage, /tmp here is just
# example sakes.
dataDir=/var/zookeeper
# the port at which the clients will connect
clientPort=2181
# the maximum number of client connections.
# increase this if you need to handle more clients
#maxClientCnxns=60
#
# Be sure to read the maintenance section of the
# administrator guide before turning on autopurge.
#
# http://zookeeper.apache.org/doc/current/zookeeperAdmin.html#sc_maintenance
#
# The number of snapshots to retain in dataDir
#autopurge.snapRetainCount=3
# Purge task interval in hours
# Set to "0" to disable auto purge feature
#autopurge.purgeInterval=1

server.1=172.16.30.100:2888:3888
server.2=172.16.30.101:2888:3888
server.3=172.16.30.102:2888:3888
 

主要修改加粗部分，配置三個節點

3.啟動節點

zookeeper是基於java開發的，所以執行zookeeper需要java環境。安裝好jdk之後，在/etc/bashrc里加入java環境

export JAVA_HOME=/home/hadoop/env/jdk1.7.0_80
export CLASSPATH=.:$JAVA_HOME/jre/lib/rt.jar:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export PATH=$JAVA_HOME/bin:$PATH

然後通過./bin/zkServer.sh start啟動zookeeper節點。 啟動之後，可以通過telnet 驗證服務

telnet 172.16.30.100:2181
Trying 172.16.30.100...
Connected to 172.16.30.100.
Escape character is '^]'.

如上，說明zookeeper節點服務已經啟動，鍵入stat，如果返回下面內容，說明叢集已經正常工作

Zookeeper version: 3.4.12-e5259e437540f349646870ea94dc2658c4e44b3b, built on 03/27/2018 03:55 GMT
Clients:
 /172.16.30.100:39281[0](queued=0,recved=1,sent=0)

Latency min/avg/max: 0/0/0
Received: 2
Sent: 1
Connections: 1
Outstanding: 0
Zxid: 0x100000040
Mode: follower
Node count: 19
Connection closed by foreign host.
 

正常情況下，當叢集裡超過半數節點啟動，zookeeper叢集才會正常執行，允許外部連線。

4.常用命令

通過zkCli.sh連線zookeeper服務

./bin/zkCli.sh -timeout 5000 -server 172.16.30.101:2181
WatchedEvent state:SyncConnected type:None path:null
[zk: 172.16.30.101:2181(CONNECTED) 0]

如上所示，連線成功，等待執行命令。

鍵入h，回車

ZooKeeper -server host:port cmd args
        connect host:port
        get path [watch]
        ls path [watch]
        set path data [version]
        rmr path
        delquota [-n|-b] path
        quit 
        printwatches on|off
        create [-s] [-e] path data acl
        stat path [watch]
        close 
        ls2 path [watch]
        history 
        listquota path
        setAcl path acl
        getAcl path
        sync path
        redo cmdno
        addauth scheme auth
        delete path [version]
        setquota -n|-b val path

可以看到一堆命令

connect …是連線到其他節點 get path 檢視當前路徑znode的資訊(包含data) ls path 檢視當前路徑的子znode set path… 設定當前路徑znode資料 rmr path… 遞迴刪除當前路徑節點及所有子節點 delquota… 刪除策略，-n代表子節點數量，-b代表資料長度 quit 退出 create 建立節點，-s代表持久，-e代表臨時 stat path… 檢視某路徑節點狀態 close 關閉連線 ls2 path… 檢視當前路徑子節點和當前節點狀態 history 列出歷史執行命令清單 listquota… 檢視當前路徑節點策略情況 delete path刪除當前路徑節點 setquota 設定路徑節點策略