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。
系统环境：
~ uname -a Linux conan 3.5.0-23-generic #35~precise1-Ubuntu SMP Fri Jan 25 17:13:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux ~ cat /etc/issue Ubuntu 12.04.2 LTS \n \l ~ java -version java version "1.6.0_29" Java(TM) SE Runtime Environment (build 1.6.0_29-b11) Java HotSpot(TM) 64-Bit Server VM (build 20.4-b02, mixed mode)
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 ckTime=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 ... STOPPED
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 ckTime=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 ckTime=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=192.168.1.201:2890:3890
3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 files
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 path
ZooKeeper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 down
/**
* Copyright (c) 2006-2015 Hzins Ltd. All Rights Reserved.
*
* This code is the confidential and proprietary information of
* Hzins. You shall not disclose such Confidential Information
* and shall use it only in accordance with the terms of the agreements
* you entered into with Hzins,http://www.hzins.com.
*
*/
package cllient.zookeeper;
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;
import org.junit.Test;
/**
* <p>
*
* zookeeper测试
*
* </p>
*
* @author hz14121005
* @date 2015-8-28 下午3:45:01
* @version
*/
public class ZookeeperTest {
@Test
public void testZookeeper() throws IOException, KeeperException, InterruptedException {
Watcher watcher = new Watcher() {
@Override
public void process(WatchedEvent event) {
System.out.println(event.toString());
}
};
// 创建一个与服务器的连接
ZooKeeper zk = new ZooKeeper("192.168.10.38:2181", 5000, watcher);
// 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();
}
}
版权声明：本文为博主原创文章，未经博主允许不得转载。
原文：http://blog.csdn.net/dandan2zhuzhu/article/details/48054185