一、解压
tar -zxvf zookeeper-3.3.5.tar.gz
二、将zookeeper-3.3.4/conf目录下面的 zoo_sample.cfg修改为zoo.cfg，配置文件内容如下所示：
tickTime= #该参数用来定义心跳的间隔时间，zookeeper的客户端和服务端之间也有和web开发里类似的session的概念，而zookeeper里最小的session过期时间就是tickTime的两倍。
dataDir=/home/hadoop/storage/zookeeper #为存储在内存中的数据库快照功能
clientPort= #是监听客户端连接的端口号。
initLimit= #是指follower连接并同步到leader的初始化连接，它是通过tickTime的倍数表示，例如我们上面的配置就是10倍的tickTime，当初始化连接时间超过设置的倍数时候则连接失败。
syncLimit= #是指follower和leader之间发送消息时请求和应答的时间长度，如果follower在设置的时间范围内不能和leader通信，那么该follower将会被丢弃，它也是按tickTime的倍数进行设置的。
三、下面启动ZooKeeper服务器进程：
cd zookeeper-3.3./
bin/zkServer.sh start
四、在客户端连接ZooKeeper服务器，执行如下命令：
bin/zkCli.sh -server dynamic:
上面dynamic是我的主机名，如果在本机执行，则执行如下命令即可：
bin/zkCli.sh
五、客户端连接信息如下所示：
hadoop@master:~/installation/zookeeper-3.3.$ bin/zkCli.sh -server dynamic:
Connecting to dynamic:
-- ::, - INFO [main:Environment@] - Client environment:zookeeper.version=3.3.-, built on // : GMT
-- ::, - INFO [main:Environment@] - Client environment:host.name=master
-- ::, - INFO [main:Environment@] - Client environment:java.version=1.6.0_30
-- ::, - INFO [main:Environment@] - Client environment:java.vendor=Sun Microsystems Inc.
-- ::, - INFO [main:Environment@] - Client environment:java.home=/home/hadoop/installation/jdk1..0_30/jre
-- ::, - INFO [main:Environment@] - Client environment:java.class.path=/home/hadoop/installation/zookeeper-3.3./bin/../build/classes:/home/hadoop/installation/zookeeper-3.3./bin/../build/lib/*.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../zookeeper-3.3.4.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/log4j-1.2.15.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/jline-0.9.94.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/commons-lang-2.4.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/commons-collections-3.2.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/commons-cli-1.1.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/apache-rat-tasks-0.6.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/apache-rat-core-0.6.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../src/java/lib/*.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../conf:/home/hadoop/installation/jdk1.6.0_30/lib/*.jar:/home/hadoop/installation/jdk1.6.0_30/jre/lib/*.jar
2012-01-08 21:30:06,206 - INFO [main:Environment@97] - Client environment:java.library.path=/home/hadoop/installation/jdk1.6.0_30/jre/lib/i386/client:/home/hadoop/installation/jdk1.6.0_30/jre/lib/i386:/home/hadoop/installation/jdk1.6.0_30/jre/../lib/i386:/usr/java/packages/lib/i386:/lib:/usr/lib
2012-01-08 21:30:06,213 - INFO [main:Environment@97] - Client environment:java.io.tmpdir=/tmp
2012-01-08 21:30:06,216 - INFO [main:Environment@97] - Client environment:java.compiler=<NA>
2012-01-08 21:30:06,235 - INFO [main:Environment@97] - Client environment:os.name=Linux
2012-01-08 21:30:06,244 - INFO [main:Environment@97] - Client environment:os.arch=i386
2012-01-08 21:30:06,246 - INFO [main:Environment@97] - Client environment:os.version=3.0.0-14-generic
2012-01-08 21:30:06,251 - INFO [main:Environment@97] - Client environment:user.name=hadoop
2012-01-08 21:30:06,254 - INFO [main:Environment@97] - Client environment:user.home=/home/hadoop
2012-01-08 21:30:06,255 - INFO [main:Environment@97] - Client environment:user.dir=/home/hadoop/installation/zookeeper-3.3.4
2012-01-08 21:30:06,264 - INFO [main:ZooKeeper@379] - Initiating client connection, connectString=dynamic:2181 sessionTimeout=30000 watcher=org.apache.zookeeper.ZooKeeperMain$MyWatcher@bf32c
2012-01-08 21:30:06,339 - INFO [main-SendThread():ClientCnxn$SendThread@1061] - Opening socket connection to server dynamic/192.168.0.107:2181
Welcome to ZooKeeper!
2012-01-08 21:30:06,397 - INFO [main-SendThread(dynamic:2181):ClientCnxn$SendThread@950] - Socket connection established to dynamic/192.168.0.107:2181, initiating session
JLine support is enabled
2012-01-08 21:30:06,492 - INFO [main-SendThread(dynamic:2181):ClientCnxn$SendThread@739] - Session establishment complete on server dynamic/192.168.0.107:2181, sessionid = 0x134b9b714f9000c, negotiated timeout = 30000 WATCHER:: WatchedEvent state:SyncConnected type:None path:null
[zk: dynamic:2181(CONNECTED) 0]
六、集群配置
1、hosts文件如下：
192.168.0.179 slave-
192.168.0.178 slave-
192.168.0.177 slave-
2、在其中一台机器（slave-01）上，解压缩zookeeper-3.3.4.tar.gz，修改配置文件conf/zoo.cfg，内容如下所示：
tickTime=
dataDir=/home/hadoop/storage/zookeeper
clientPort=
initLimit=
syncLimit=
server.=slave-::
server.=slave-::
server.=slave-::
是用于进行leader选举的端口，是zookeeper集群里各个机器之间的通信接口。
3、远程复制分发安装文件
上面已经在一台机器slave-01上配置完成ZooKeeper，现在可以将该配置好的安装文件远程拷贝到集群中的各个结点对应的conf/目录下。
4、设置myid
hadoop@slave-:~/installation/zookeeper-3.3.$ echo "" > /home/hadoop/storage/zookeeper/myid
hadoop@slave-:~/installation/zookeeper-3.3.$ echo "" > /home/hadoop/storage/zookeeper/myid
hadoop@slave-:~/installation/zookeeper-3.3.$ echo "" > /home/hadoop/storage/zookeeper/myid
5、启动ZooKeeper集群
在ZooKeeper集群的每个结点上，执行启动ZooKeeper服务的脚本，如下所示：
hadoop@slave-:~/installation/zookeeper-3.3.$ bin/zkServer.sh start
hadoop@slave-:~/installation/zookeeper-3.3.$ bin/zkServer.sh start
hadoop@slave-:~/installation/zookeeper-3.3.$ bin/zkServer.sh start
以结点slave-01为例，日志如下所示：
hadoop@slave-:~/installation/zookeeper-3.3.$ tail -500f zookeeper.out
-- ::, - INFO [main:QuorumPeerConfig@] - Reading configuration from: /home/hadoop/installation/zookeeper-3.3./bin/../conf/zoo.cfg
-- ::, - INFO [main:QuorumPeerConfig@] - Defaulting to majority quorums
-- ::, - INFO [main:QuorumPeerMain@] - Starting quorum peer
-- ::, - INFO [main:NIOServerCnxn$Factory@] - binding to port 0.0.0.0/0.0.0.0:
-- ::, - INFO [main:QuorumPeer@] - tickTime set to
-- ::, - INFO [main:QuorumPeer@] - minSessionTimeout set to -
-- ::, - INFO [main:QuorumPeer@] - maxSessionTimeout set to -
-- ::, - INFO [main:QuorumPeer@] - initLimit set to
-- ::, - INFO [Thread-:QuorumCnxManager$Listener@] - My election bind port:
-- ::, - INFO [QuorumPeer:/:::::::::QuorumPeer@] - LOOKING
-- ::, - INFO [QuorumPeer:/:::::::::FastLeaderElection@] - New election. My id = , Proposed zxid =
-- ::, - INFO [WorkerReceiver Thread:FastLeaderElection@] - Notification: (n.leader), (n.zxid), (n.round), LOOKING (n.state), (n.sid), LOOKING (my state)
-- ::, - WARN [WorkerSender Thread:QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.178:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.toSend(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.process(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.run(FastLeaderElection.java:)
at java.lang.Thread.run(Thread.java:)
-- ::, - WARN [WorkerSender Thread:QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.177:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.toSend(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.process(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.run(FastLeaderElection.java:)
at java.lang.Thread.run(Thread.java:)
-- ::, - WARN [QuorumPeer:/:::::::::QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.178:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:)
-- ::, - WARN [QuorumPeer:/:::::::::QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.177:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:)
-- ::, - INFO [QuorumPeer:/:::::::::FastLeaderElection@] - Notification time out:
-- ::, - WARN [QuorumPeer:/:::::::::QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.178:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:)
-- ::, - WARN [QuorumPeer:/:::::::::QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.177:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:)
-- ::, - INFO [QuorumPeer:/:::::::::FastLeaderElection@] - Notification time out:
-- ::, - WARN [QuorumPeer:/:::::::::QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.178:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:)
-- ::, - WARN [QuorumPeer:/:::::::::QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.177:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:)
-- ::, - INFO [QuorumPeer:/:::::::::FastLeaderElection@] - Notification time out:
-- ::, - WARN [QuorumPeer:/:::::::::QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.178:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:)
-- ::, - WARN [QuorumPeer:/:::::::::QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.177:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectAll(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection.lookForLeader(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.QuorumPeer.run(QuorumPeer.java:)
-- ::, - INFO [QuorumPeer:/:::::::::FastLeaderElection@] - Notification time out:
-- ::, - INFO [WorkerReceiver Thread:FastLeaderElection@] - Notification: (n.leader), (n.zxid), (n.round), LOOKING (n.state), (n.sid), LOOKING (my state)
-- ::, - INFO [QuorumPeer:/:::::::::FastLeaderElection@] - Updating proposal
-- ::, - WARN [WorkerSender Thread:QuorumCnxManager@] - Cannot open channel to at election address slave-/192.168.0.177:
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.QuorumCnxManager.toSend(QuorumCnxManager.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.process(FastLeaderElection.java:)
at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.run(FastLeaderElection.java:)
at java.lang.Thread.run(Thread.java:)
-- ::, - INFO [WorkerReceiver Thread:FastLeaderElection@] - Notification: (n.leader), (n.zxid), (n.round), LOOKING (n.state), (n.sid), LOOKING (my state)
-- ::, - INFO [QuorumPeer:/:::::::::QuorumPeer@] - FOLLOWING
-- ::, - INFO [QuorumPeer:/:::::::::Learner@] - TCP NoDelay set to: true
-- ::, - INFO [QuorumPeer:/:::::::::Environment@] - Server environment:zookeeper.version=3.3.-, built on // : GMT
-- ::, - INFO [QuorumPeer:/:::::::::Environment@] - Server environment:host.name=slave-
-- ::, - INFO [QuorumPeer:/:::::::::Environment@] - Server environment:java.version=1.6.0_30
-- ::, - INFO [QuorumPeer:/:::::::::Environment@] - Server environment:java.vendor=Sun Microsystems Inc.
-- ::, - INFO [QuorumPeer:/:::::::::Environment@] - Server environment:java.home=/home/hadoop/installation/jdk1..0_30/jre
-- ::, - INFO [QuorumPeer:/:::::::::Environment@] - Server environment:java.class.path=/home/hadoop/installation/zookeeper-3.3./bin/../build/classes:/home/hadoop/installation/zookeeper-3.3./bin/../build/lib/*.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../zookeeper-3.3.4.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/log4j-1.2.15.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/jline-0.9.94.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/commons-lang-2.4.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/commons-collections-3.2.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/commons-cli-1.1.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/apache-rat-tasks-0.6.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/apache-rat-core-0.6.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../src/java/lib/*.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../conf:/home/hadoop/installation/jdk1.6.0_30/lib/*.jar:/home/hadoop/installation/jdk1.6.0_30/jre/lib/*.jar
2012-01-08 06:51:23,210 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Environment@97] - Server environment:java.library.path=/home/hadoop/installation/jdk1.6.0_30/jre/lib/i386/client:/home/hadoop/installation/jdk1.6.0_30/jre/lib/i386:/home/hadoop/installation/jdk1.6.0_30/jre/../lib/i386:/usr/java/packages/lib/i386:/lib:/usr/lib
2012-01-08 06:51:23,210 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Environment@97] - Server environment:java.io.tmpdir=/tmp
2012-01-08 06:51:23,212 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Environment@97] - Server environment:java.compiler=<NA>
2012-01-08 06:51:23,212 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Environment@97] - Server environment:os.name=Linux
2012-01-08 06:51:23,212 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Environment@97] - Server environment:os.arch=i386
2012-01-08 06:51:23,213 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Environment@97] - Server environment:os.version=3.0.0-14-generic
2012-01-08 06:51:23,213 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Environment@97] - Server environment:user.name=hadoop
2012-01-08 06:51:23,214 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Environment@97] - Server environment:user.home=/home/hadoop
2012-01-08 06:51:23,214 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Environment@97] - Server environment:user.dir=/home/hadoop/installation/zookeeper-3.3.4
2012-01-08 06:51:23,223 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:ZooKeeperServer@151] - Created server with tickTime 2000 minSessionTimeout 4000 maxSessionTimeout 40000 datadir /home/hadoop/storage/zookeeper/version-2 snapdir /home/hadoop/storage/zookeeper/version-2
2012-01-08 06:51:23,339 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Learner@294] - Getting a snapshot from leader
2012-01-08 06:51:23,358 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:Learner@325] - Setting leader epoch 1
2012-01-08 06:51:23,358 - INFO [QuorumPeer:/0:0:0:0:0:0:0:0:2181:FileTxnSnapLog@254] - Snapshotting: 0
2012-01-08 06:51:25,511 - INFO [WorkerReceiver Thread:FastLeaderElection@496] - Notification: 3 (n.leader), 0 (n.zxid), 1 (n.round), LOOKING (n.state), 3 (n.sid), FOLLOWING (my state)
2012-01-08 06:51:42,584 - INFO [WorkerReceiver Thread:FastLeaderElection@496] - Notification: 3 (n.leader), 0 (n.zxid), 2 (n.round), LOOKING (n.state), 3 (n.sid), FOLLOWING (my state)
6、安装验证
可以通过ZooKeeper的脚本来查看启动状态，包括集群中各个结点的角色（或是Leader，或是Follower），如下所示，是在ZooKeeper集群中的每个结点上查询的结果：
hadoop@slave-:~/installation/zookeeper-3.3.$ bin/zkServer.sh status
JMX enabled by default
Using config: /home/hadoop/installation/zookeeper-3.3./bin/../conf/zoo.cfg
Mode: follower hadoop@slave-:~/installation/zookeeper-3.3.$ bin/zkServer.sh status
JMX enabled by default
Using config: /home/hadoop/installation/zookeeper-3.3./bin/../conf/zoo.cfg
Mode: leader hadoop@slave-:~/installation/zookeeper-3.3.$ bin/zkServer.sh status
JMX enabled by default
Using config: /home/hadoop/installation/zookeeper-3.3./bin/../conf/zoo.cfg
Mode: follower
7、另外，可以通过客户端脚本，连接到ZooKeeper集群上。对于客户端来说，ZooKeeper是一个整体（ensemble），连接到ZooKeeper集群实际上感觉在独享整个集群的服务，所以，你可以在任何一个结点上建立到服务集群的连接，例如：
hadoop@slave-:~/installation/zookeeper-3.3.$ bin/zkCli.sh -server slave-:
Connecting to slave-:
-- ::, - INFO [main:Environment@] - Client environment:zookeeper.version=3.3.-, built on // : GMT
-- ::, - INFO [main:Environment@] - Client environment:host.name=slave-
-- ::, - INFO [main:Environment@] - Client environment:java.version=1.6.0_30
-- ::, - INFO [main:Environment@] - Client environment:java.vendor=Sun Microsystems Inc.
-- ::, - INFO [main:Environment@] - Client environment:java.home=/home/hadoop/installation/jdk1..0_30/jre
-- ::, - INFO [main:Environment@] - Client environment:java.class.path=/home/hadoop/installation/zookeeper-3.3./bin/../build/classes:/home/hadoop/installation/zookeeper-3.3./bin/../build/lib/*.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../zookeeper-3.3.4.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/log4j-1.2.15.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/jline-0.9.94.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/commons-lang-2.4.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/commons-collections-3.2.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/commons-cli-1.1.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/apache-rat-tasks-0.6.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../lib/apache-rat-core-0.6.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../src/java/lib/*.jar:/home/hadoop/installation/zookeeper-3.3.4/bin/../conf:/home/hadoop/installation/jdk1.6.0_30/lib/*.jar:/home/hadoop/installation/jdk1.6.0_30/jre/lib/*.jar
2012-01-08 07:14:21,111 - INFO [main:Environment@97] - Client environment:java.library.path=/home/hadoop/installation/jdk1.6.0_30/jre/lib/i386/client:/home/hadoop/installation/jdk1.6.0_30/jre/lib/i386:/home/hadoop/installation/jdk1.6.0_30/jre/../lib/i386:/usr/java/packages/lib/i386:/lib:/usr/lib
2012-01-08 07:14:21,116 - INFO [main:Environment@97] - Client environment:java.io.tmpdir=/tmp
2012-01-08 07:14:21,124 - INFO [main:Environment@97] - Client environment:java.compiler=<NA>
2012-01-08 07:14:21,169 - INFO [main:Environment@97] - Client environment:os.name=Linux
2012-01-08 07:14:21,175 - INFO [main:Environment@97] - Client environment:os.arch=i386
2012-01-08 07:14:21,177 - INFO [main:Environment@97] - Client environment:os.version=3.0.0-14-generic
2012-01-08 07:14:21,185 - INFO [main:Environment@97] - Client environment:user.name=hadoop
2012-01-08 07:14:21,188 - INFO [main:Environment@97] - Client environment:user.home=/home/hadoop
2012-01-08 07:14:21,190 - INFO [main:Environment@97] - Client environment:user.dir=/home/hadoop/installation/zookeeper-3.3.4
2012-01-08 07:14:21,197 - INFO [main:ZooKeeper@379] - Initiating client connection, connectString=slave-01:2181 sessionTimeout=30000 watcher=org.apache.zookeeper.ZooKeeperMain$MyWatcher@bf32c
2012-01-08 07:14:21,305 - INFO [main-SendThread():ClientCnxn$SendThread@1061] - Opening socket connection to server slave-01/192.168.0.179:2181
Welcome to ZooKeeper!
2012-01-08 07:14:21,376 - INFO [main-SendThread(slave-01:2181):ClientCnxn$SendThread@950] - Socket connection established to slave-01/192.168.0.179:2181, initiating session
JLine support is enabled
[zk: slave-01:2181(CONNECTING) 0] 2012-01-08 07:14:21,872 - INFO [main-SendThread(slave-01:2181):ClientCnxn$SendThread@739] - Session establishment complete on server slave-01/192.168.0.179:2181, sessionid = 0x134bdcd6b730000, negotiated timeout = 30000 WATCHER:: WatchedEvent state:SyncConnected type:None path:null [zk: slave-01:2181(CONNECTED) 0] ls /
[zookeeper]