1. zookeeper介绍
ZooKeeper是一个为分布式应用所设计的分布的、开源的协调服务，它主要是用来解决分布式应用中经常遇到的一些数据管理问题，简化分布式应用协调及其管理的难度，提供高性能的分布式服务。ZooKeeper本身可以以Standalone模式安装运行，不过它的长处在于通过分布式ZooKeeper集群（一个Leader，多个Follower），基于一定的策略来保证ZooKeeper集群的稳定性和可用性，从而实现分布式应用的可靠性。
ZooKeeper是作为分布式协调服务，是不需要依赖于Hadoop的环境，也可以为其他的分布式环境提供服务。
2. zookeeper单节点安装Standalones模式
系统环境：
- Linux Ubuntu 12.04.2 LTS 64bit server
- Java: 1.6.0_29 64-Bit Server VM
-
下载zookeeper
~ mkdir /home/conan/toolkit ~ cd /home/conan/toolkit ~ wget http://apache.dataguru.cn/zookeeper/stable/zookeeper-3.4.5.tar.gz ~ tar xvf zookeeper-3.4.5.tar.gz ~ mv zookeeper-3.4.5 zookeeper345 ~ cd zookeeper345 ~ ls -l drwxr-xr-x 2 conan conan 4096 Aug 12 04:34 bin -rw-r--r-- 1 conan conan 75988 Aug 12 04:34 build.xml -rw-r--r-- 1 conan conan 70223 Aug 12 04:34 CHANGES.txt drwxr-xr-x 2 conan conan 4096 Aug 12 04:34 conf drwxr-xr-x 10 conan conan 4096 Aug 12 04:34 contrib drwxr-xr-x 2 conan conan 4096 Aug 12 04:34 dist-maven drwxr-xr-x 6 conan conan 4096 Aug 12 04:34 docs -rw-r--r-- 1 conan conan 1953 Aug 12 04:34 ivysettings.xml -rw-r--r-- 1 conan conan 3120 Aug 12 04:34 ivy.xml drwxr-xr-x 4 conan conan 4096 Aug 12 04:34 lib -rw-r--r-- 1 conan conan 11358 Aug 12 04:34 LICENSE.txt -rw-r--r-- 1 conan conan 170 Aug 12 04:34 NOTICE.txt -rw-r--r-- 1 conan conan 1770 Aug 12 04:34 README_packaging.txt -rw-r--r-- 1 conan conan 1585 Aug 12 04:34 README.txt drwxr-xr-x 5 conan conan 4096 Aug 12 04:34 recipes drwxr-xr-x 8 conan conan 4096 Aug 12 04:34 src -rw-r--r-- 1 conan conan 1315806 Aug 12 04:34 zookeeper-3.4.5.jar -rw-r--r-- 1 conan conan 833 Aug 12 04:34 zookeeper-3.4.5.jar.asc -rw-r--r-- 1 conan conan 33 Aug 12 04:34 zookeeper-3.4.5.jar.md5 -rw-r--r-- 1 conan conan 41 Aug 12 04:34 zookeeper-3.4.5.jar.sha1 -
修改配置文件conf/zoo.cfg
~ mkdir /home/conan/zoo/zk0 ~ cp conf/zoo_sample.cfg conf/zoo.cfg ~ vi conf/zoo.cfg tickTime=2000 initLimit=10 syncLimit=5 dataDir=/home/conan/zoo/zk0 clientPort=2181非常简单，我们已经配置好了的zookeeper单节点
启动zookeeper
~ bin/zkServer.sh JMX enabled by default Using config: /home/conan/zoo/zk0/zookeeper345/bin/../conf/zoo.cfg Usage: bin/zkServer.sh {start|start-foreground|stop|restart|status|upgrade|print-cmd} conan@conan:~/zoo/zk0/zookeeper345$ bin/zkServer.sh start JMX enabled by default Using config: /home/conan/zoo/zk0/zookeeper345/bin/../conf/zoo.cfg Starting zookeeper ... STARTED #zk的服务显示为QuorumPeerMain ~ jps 5321 QuorumPeerMain 5338 Jps #查看运行状态 ~ bin/zkServer.sh status JMX enabled by default Using config: /home/conan/zoo/zk0/zookeeper345/bin/../conf/zoo.cfg Mode: standalone单节点的时，Mode会显示为standalone
停止ZooKeeper服务
~ bin/zkServer.sh stop JMX enabled by default Using config: /home/conan/zoo/zk0/zookeeper345/bin/../conf/zoo.cfg Stopping zookeeper ... STOPPED3. zookeeper伪分布式集群安装
所谓 “伪分布式集群” 就是在，在一台PC中，启动多个ZooKeeper的实例。“完全分布式集群” 是每台PC，启动一个ZooKeeper实例。
由于我的测试环境PC数量有限，所以在一台PC中，启动3个ZooKeeper的实例。
创建环境目录
~ mkdir /home/conan/zoo/zk1 ~ mkdir /home/conan/zoo/zk2 ~ mkdir /home/conan/zoo/zk3 #新建myid文件 ~ echo "1" > /home/conan/zoo/zk1/myid ~ echo "2" > /home/conan/zoo/zk2/myid ~ echo "3" > /home/conan/zoo/zk3/myid分别修改配置文件
修改：dataDir,clientPort
增加：集群的实例，server.X，”X”表示每个目录中的myid的值~ vi /home/conan/toolkit/zookeeper345/conf/zk1.cfg tickTime=2000 initLimit=10 syncLimit=5 dataDir=/home/conan/zoo/zk1 clientPort=2181 server.1=192.168.1.201:2888:3888 server.2=192.168.1.201:2889:3889 server.3=192.168.1.201:2890:3890 ~ vi /home/conan/toolkit/zookeeper345/conf/zk2.cfg tickTime=2000 initLimit=10 syncLimit=5 dataDir=/home/conan/zoo/zk2 clientPort=2182 server.1=192.168.1.201:2888:3888 server.2=192.168.1.201:2889:3889 server.3=192.168.1.201:2890:3890 ~ vi /home/conan/toolkit/zookeeper345/conf/zk3.cfg tickTime=2000 initLimit=10 syncLimit=5 dataDir=/home/conan/zoo/zk3 clientPort=2183 server.1=192.168.1.201:2888:3888 server.2=192.168.1.201:2889:3889 server.3=192.168.1.201:2890:38903个节点的ZooKeeper集群配置完成，接下来我们的启动服务。
启动集群
~ /home/conan/toolkit/zookeeper345/bin/zkServer.sh start zk1.cfg ~ /home/conan/toolkit/zookeeper345/bin/zkServer.sh start zk2.cfg ~ /home/conan/toolkit/zookeeper345/bin/zkServer.sh start zk3.cfg ~ jps 5422 QuorumPeerMain 5395 QuorumPeerMain 5463 QuorumPeerMain 5494 Jps #查看节点状态 ~ /home/conan/toolkit/zookeeper345/bin/zkServer.sh status zk1.cfg JMX enabled by default Using config: /home/conan/toolkit/zookeeper345/bin/../conf/zk1.cfg Mode: follower ~ /home/conan/toolkit/zookeeper345/bin/zkServer.sh status zk2.cfg JMX enabled by default Using config: /home/conan/toolkit/zookeeper345/bin/../conf/zk2.cfg Mode: leader ~ /home/conan/toolkit/zookeeper345/bin/zkServer.sh status zk3.cfg JMX enabled by default Using config: /home/conan/toolkit/zookeeper345/bin/../conf/zk3.cfg Mode: follower我们可以看到zk2是leader，zk1和zk3是follower
查看ZooKeeper物理文件目录结构
~ tree -L 3 /home/conan/zoo /home/conan/zoo ├── zk0 ├── zk1 │ ├── myid │ ├── version-2 │ │ ├── acceptedEpoch │ │ ├── currentEpoch │ │ ├── log.100000001 │ │ └── snapshot.0 │ └── zookeeper_server.pid ├── zk2 │ ├── myid │ ├── version-2 │ │ ├── acceptedEpoch │ │ ├── currentEpoch │ │ ├── log.100000001 │ │ └── snapshot.0 │ └── zookeeper_server.pid └── zk3 ├── myid ├── version-2 │ ├── acceptedEpoch │ ├── currentEpoch │ ├── log.100000001 │ └── snapshot.100000000 └── zookeeper_server.pid 7 directories, 18 files4. zookeeper命令行操作
我们通过客户端连接ZooKeeper的集群，我们可以任意的zookeeper是进行连接。
~ /home/conan/toolkit/zookeeper345/bin/zkCli.sh -server 192.168.1.201:2181 Connecting to 192.168.1.201 2013-08-12 05:25:39,260 [myid:] - INFO [main:Environment@100] - Client environment:zookeeper.version=3.4.5-1392090, built on 09/30/2012 17:52 GMT 2013-08-12 05:25:39,267 [myid:] - INFO [main:Environment@100] - Client environment:host.name=conan 2013-08-12 05:25:39,269 [myid:] - INFO [main:Environment@100] - Client environment:java.version=1.6.0_29 2013-08-12 05:25:39,269 [myid:] - INFO [main:Environment@100] - Client environment:java.vendor=Sun Microsystems Inc. 2013-08-12 05:25:39,270 [myid:] - INFO [main:Environment@100] - Client environment:java.home=/home/conan/toolkit/jdk16/jre 2013-08-12 05:25:39,270 [myid:] - INFO [main:Environment@100] - Client environment:java.class.path=/home/conan/toolkit/zookeeper345/bin/../build/classes:/home/conan/toolkit/zookeeper345/bin/../build/lib/*.jar:/home/conan/toolkit/zookeeper345/bin/../lib/slf4j-log4j12-1.6.1.jar:/home/conan/toolkit/zookeeper345/bin/../lib/slf4j-api-1.6.1.jar:/home/conan/toolkit/zookeeper345/bin/../lib/netty-3.2.2.Final.jar:/home/conan/toolkit/zookeeper345/bin/../lib/log4j-1.2.15.jar:/home/conan/toolkit/zookeeper345/bin/../lib/jline-0.9.94.jar:/home/conan/toolkit/zookeeper345/bin/../zookeeper-3.4.5.jar:/home/conan/toolkit/zookeeper345/bin/../src/java/lib/*.jar:/home/conan/toolkit/zookeeper345/bin/../conf: 2013-08-12 05:25:39,271 [myid:] - INFO [main:Environment@100] - Client environment:java.library.path=/home/conan/toolkit/jdk16/jre/lib/amd64/server:/home/conan/toolkit/jdk16/jre/lib/amd64:/home/conan/toolkit/jdk16/jre/../lib/amd64:/usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib 2013-08-12 05:25:39,275 [myid:] - INFO [main:Environment@100] - Client environment:java.io.tmpdir=/tmp 2013-08-12 05:25:39,276 [myid:] - INFO [main:Environment@100] - Client environment:java.compiler= 2013-08-12 05:25:39,276 [myid:] - INFO [main:Environment@100] - Client environment:os.name=Linux 2013-08-12 05:25:39,277 [myid:] - INFO [main:Environment@100] - Client environment:os.arch=amd64 2013-08-12 05:25:39,281 [myid:] - INFO [main:Environment@100] - Client environment:os.version=3.5.0-23-generic 2013-08-12 05:25:39,282 [myid:] - INFO [main:Environment@100] - Client environment:user.name=conan 2013-08-12 05:25:39,282 [myid:] - INFO [main:Environment@100] - Client environment:user.home=/home/conan 2013-08-12 05:25:39,283 [myid:] - INFO [main:Environment@100] - Client environment:user.dir=/home/conan/zoo 2013-08-12 05:25:39,284 [myid:] - INFO [main:ZooKeeper@438] - Initiating client connection, connectString=192.168.1.201 sessionTimeout=30000 watcher=org.apache.zookeeper.ZooKeeperMain$MyWatcher@22ba6c83 Welcome to ZooKeeper! JLine support is enabled [zk: 192.168.1.201(CONNECTING) 0] 2013-08-12 05:25:39,336 [myid:] - INFO [main-SendThread(192.168.1.201:2181):ClientCnxn$SendThread@966] - Opening socket connection to server 192.168.1.201/192.168.1.201:2181. Will not attempt to authenticate using SASL (Unable to locate a login configuration) 2013-08-12 05:25:39,345 [myid:] - INFO [main-SendThread(192.168.1.201:2181):ClientCnxn$SendThread@849] - Socket connection established to 192.168.1.201/192.168.1.201:2181, initiating session 2013-08-12 05:25:39,384 [myid:] - INFO [main-SendThread(192.168.1.201:2181):ClientCnxn$SendThread@1207] - Session establishment complete on server 192.168.1.201/192.168.1.201:2181, sessionid = 0x1406f3c1ef90001, negotiated timeout = 30000 WATCHER:: WatchedEvent state:SyncConnected type:None path:null [zk: 192.168.1.201(CONNECTED) 0]集群已连接，下面我们要使用一下，ZooKeeper的命令行操作。
命令行操作
通过help打印命令行帮助[zk: 192.168.1.201(CONNECTED) 1] help 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 pathZooKeeper的结构，很像是目录结构，我们看到了像ls这样熟悉的命令。
#ls,查看/目录内容 [zk: 192.168.1.201(CONNECTED) 1] ls / [zookeeper] #create,创建一个znode节点 [zk: 192.168.1.201(CONNECTED) 2] create /node conan Created /node #ls,再查看/目录 [zk: 192.168.1.201(CONNECTED) 3] ls / [node, zookeeper] #get,查看/node的数据信息 [zk: 192.168.1.201(CONNECTED) 4] get /node conan cZxid = 0x100000006 ctime = Mon Aug 12 05:32:49 CST 2013 mZxid = 0x100000006 mtime = Mon Aug 12 05:32:49 CST 2013 pZxid = 0x100000006 cversion = 0 dataVersion = 0 aclVersion = 0 ephemeralOwner = 0x0 dataLength = 5 numChildren = 0 #set,修改数据 [zk: 192.168.1.201(CONNECTED) 5] set /node fens.me cZxid = 0x100000006 ctime = Mon Aug 12 05:32:49 CST 2013 mZxid = 0x100000007 mtime = Mon Aug 12 05:34:32 CST 2013 pZxid = 0x100000006 cversion = 0 dataVersion = 1 aclVersion = 0 ephemeralOwner = 0x0 dataLength = 7 numChildren = 0 #get,再查看/node的数据信息，已改为fens.me [zk: 192.168.1.201(CONNECTED) 6] get /node fens.me cZxid = 0x100000006 ctime = Mon Aug 12 05:32:49 CST 2013 mZxid = 0x100000007 mtime = Mon Aug 12 05:34:32 CST 2013 pZxid = 0x100000006 cversion = 0 dataVersion = 1 aclVersion = 0 ephemeralOwner = 0x0 dataLength = 7 numChildren = 0 #delete,删除/node [zk: 192.168.1.201(CONNECTED) 7] delete /node [zk: 192.168.1.201(CONNECTED) 8] ls / [zookeeper] #quit,退出客户端连接 [zk: 192.168.1.201(CONNECTED) 19] quit Quitting... 2013-08-12 05:40:29,304 [myid:] - INFO [main:ZooKeeper@684] - Session: 0x1406f3c1ef90002 closed 2013-08-12 05:40:29,305 [myid:] - INFO [main-EventThread:ClientCnxn$EventThread@509] - EventThread shut down5. Java编程现实命令行操作
package org.conan.zookeeper.demo; import java.io.IOException; import org.apache.zookeeper.CreateMode; import org.apache.zookeeper.KeeperException; import org.apache.zookeeper.WatchedEvent; import org.apache.zookeeper.Watcher; import org.apache.zookeeper.ZooDefs.Ids; import org.apache.zookeeper.ZooKeeper; public class BasicDemo1 { public static void main(String[] args) throws IOException, KeeperException, InterruptedException { // 创建一个与服务器的连接 ZooKeeper zk = new ZooKeeper("192.168.1.201:2181", 60000, new Watcher() { // 监控所有被触发的事件 public void process(WatchedEvent event) { System.out.println("EVENT:" + event.getType()); } }); // 查看根节点 System.out.println("ls / => " + zk.getChildren("/", true)); // 创建一个目录节点 if (zk.exists("/node", true) == null) { zk.create("/node", "conan".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT); System.out.println("create /node conan"); // 查看/node节点数据 System.out.println("get /node => " + new String(zk.getData("/node", false, null))); // 查看根节点 System.out.println("ls / => " + zk.getChildren("/", true)); } // 创建一个子目录节点 if (zk.exists("/node/sub1", true) == null) { zk.create("/node/sub1", "sub1".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT); System.out.println("create /node/sub1 sub1"); // 查看node节点 System.out.println("ls /node => " + zk.getChildren("/node", true)); } // 修改节点数据 if (zk.exists("/node", true) != null) { zk.setData("/node", "changed".getBytes(), -1); // 查看/node节点数据 System.out.println("get /node => " + new String(zk.getData("/node", false, null))); } // 删除节点 if (zk.exists("/node/sub1", true) != null) { zk.delete("/node/sub1", -1); zk.delete("/node", -1); // 查看根节点 System.out.println("ls / => " + zk.getChildren("/", true)); } // 关闭连接 zk.close(); } }运行结果：
2013-08-12 15:33:29,699 [myid:] - INFO [main:Environment@97] - Client environment:zookeeper.version=3.3.1-942149, built on 05/07/2010 17:14 GMT 2013-08-12 15:33:29,702 [myid:] - INFO [main:Environment@97] - Client environment:host.name=PC201304202140 2013-08-12 15:33:29,702 [myid:] - INFO [main:Environment@97] - Client environment:java.version=1.6.0_45 2013-08-12 15:33:29,702 [myid:] - INFO [main:Environment@97] - Client environment:java.vendor=Sun Microsystems Inc. 2013-08-12 15:33:29,702 [myid:] - INFO [main:Environment@97] - Client environment:java.home=D:\toolkit\java\jdk6\jre 2013-08-12 15:33:29,703 [myid:] - INFO [main:Environment@97] - Client environment:java.class.path=D:\workspace\java\zkdemo\target\classes;C:\Users\Administrator\.m2\repository\org\apache\hadoop\zookeeper\3.3.1\zookeeper-3.3.1.jar;C:\Users\Administrator\.m2\repository\log4j\log4j\1.2.15\log4j-1.2.15.jar;C:\Users\Administrator\.m2\repository\javax\mail\mail\1.4\mail-1.4.jar;C:\Users\Administrator\.m2\repository\javax\activation\activation\1.1\activation-1.1.jar;C:\Users\Administrator\.m2\repository\jline\jline\0.9.94\jline-0.9.94.jar;C:\Users\Administrator\.m2\repository\junit\junit\3.8.1\junit-3.8.1.jar 2013-08-12 15:33:29,703 [myid:] - INFO [main:Environment@97] - Client environment:java.library.path=D:\toolkit\java\jdk6\bin;C:\Windows\Sun\Java\bin;C:\Windows\system32;C:\Windows;D:\toolkit\Rtools\bin;D:\toolkit\Rtools\gcc-4.6.3\bin;C:\Program Files (x86)\Common Files\NetSarang;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;D:\toolkit\Git\cmd;D:\toolkit\Git\bin;C:\Program Files (x86)\Microsoft SQL Server\100\Tools\Binn\;C:\Program Files\Microsoft SQL Server\100\Tools\Binn\;C:\Program Files\Microsoft SQL Server\100\DTS\Binn\;c:\Program Files (x86)\Common Files\Ulead Systems\MPEG;C:\Program Files (x86)\QuickTime\QTSystem\;D:\toolkit\MiKTex\miktex\bin\x64\;D:\toolkit\sshclient;D:\toolkit\ant19\bin;D:\toolkit\eclipse;D:\toolkit\gradle15\bin;D:\toolkit\java\jdk6\bin;D:\toolkit\maven3\bin;D:\toolkit\mysql56\bin;D:\toolkit\python27;D:\toolkit\putty;C:\Program Files\R\R-3.0.1\bin\x64;D:\toolkit\mongodb243\bin;D:\toolkit\php54;D:\toolkit\nginx140;D:\toolkit\nodejs;D:\toolkit\npm12\bin;D:\toolkit\java\jdk6\jre\bin\server;. 2013-08-12 15:33:29,703 [myid:] - INFO [main:Environment@97] - Client environment:java.io.tmpdir=C:\Users\ADMINI~1\AppData\Local\Temp\ 2013-08-12 15:33:29,704 [myid:] - INFO [main:Environment@97] - Client environment:java.compiler= 2013-08-12 15:33:29,704 [myid:] - INFO [main:Environment@97] - Client environment:os.name=Windows 7 2013-08-12 15:33:29,704 [myid:] - INFO [main:Environment@97] - Client environment:os.arch=amd64 2013-08-12 15:33:29,705 [myid:] - INFO [main:Environment@97] - Client environment:os.version=6.1 2013-08-12 15:33:29,705 [myid:] - INFO [main:Environment@97] - Client environment:user.name=Administrator 2013-08-12 15:33:29,705 [myid:] - INFO [main:Environment@97] - Client environment:user.home=C:\Users\Administrator 2013-08-12 15:33:29,706 [myid:] - INFO [main:Environment@97] - Client environment:user.dir=D:\workspace\java\zkdemo 2013-08-12 15:33:29,707 [myid:] - INFO [main:ZooKeeper@373] - Initiating client connection, connectString=192.168.1.201:2181 sessionTimeout=60000 watcher=org.conan.zookeeper.demo.BasicDemo1$1@3dfeca64 2013-08-12 15:33:29,731 [myid:] - INFO [main-SendThread():ClientCnxn$SendThread@1000] - Opening socket connection to server /192.168.1.201:2181 2013-08-12 15:33:38,736 [myid:] - INFO [main-SendThread(192.168.1.201:2181):ClientCnxn$SendThread@908] - Socket connection established to 192.168.1.201/192.168.1.201:2181, initiating session 2013-08-12 15:33:38,804 [myid:] - INFO [main-SendThread(192.168.1.201:2181):ClientCnxn$SendThread@701] - Session establishment complete on server 192.168.1.201/192.168.1.201:2181, sessionid = 0x1406f3c1ef9000d, negotiated timeout = 60000 EVENT:None ls / => [zookeeper] EVENT:NodeCreated EVENT:NodeChildrenChanged create /node conan get /node => conan ls / => [node, zookeeper] EVENT:NodeCreated create /node/sub1 sub1 ls /node => [sub1] EVENT:NodeDataChanged get /node => changed EVENT:NodeDeleted EVENT:NodeChildrenChanged EVENT:NodeChildrenChanged ls / => [zookeeper] 2013-08-12 15:33:38,877 [myid:] - INFO [main:ZooKeeper@538] - Session: 0x1406f3c1ef9000d closedpom.xml，maven配置文件
<?xml version="1.0" encoding="UTF-8"?> <project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <modelVersion>4.0.0</modelVersion> <groupId>org.conan.zookeeper</groupId> <artifactId>zkdemo</artifactId> <version>0.0.1</version> <name>zkdemo</name> <description>zkdemo</description> <dependencies> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>zookeeper</artifactId> <version>3.3.1</version> <exclusions> <exclusion> <groupId>javax.jms</groupId> <artifactId>jms</artifactId> </exclusion> <exclusion> <groupId>com.sun.jdmk</groupId> <artifactId>jmxtools</artifactId> </exclusion> <exclusion> <groupId>com.sun.jmx</groupId> <artifactId>jmxri</artifactId> </exclusion> </exclusions> </dependency> </dependencies> </project>