zookeeper

zookeeper简介
　　1、曾经是Hadoop子项目，现为顶级项目
　　2、是分布式应用程序协同服务
　　　　ZooKeeper是一个分布式的，开放源码的分布式应用程序协调服务，是Google的Chubby一个开源的实现，是Hadoop和Hbase的重要组件。　　
　　3、为分布式应用提供一致性服务
　　　　它是一个为分布式应用提供一致性服务的软件，提供的功能包括：配置维护、域名服务、分布式同步、组服务等。
　　4、支持Java和C的接口

ZooKeeper的目标
　　就是封装好复杂易出错的关键服务，将简单易用的接口和性能高效、功能稳定的系统提供给用户。

ZooKeeper代码版本中，提供了分布式独享锁、选举、队列的接口，代码在zookeeper-3.4.3\src\recipes。其中分布锁和队列有Java和C两个版本，选举只有Java版本。

 

 

# ntpdate -s ntp1.aliyun.com

# cat /etc/hosts
192.168.0.83 node83　　作为zclient
192.168.0.84 node84
192.168.0.85 node85
192.168.0.86 node86


统一部署java环境
# rpm -ivh jdk-8u111-linux-x64.rpm
# vi /etc/profile.d/java.sh
export JAVA_HOME=/usr/java/latest/
export PATH=$JAVA_HOME:$PATH
# . /etc/profile.d/java.sh

#ls /home/tools
zookeeper-3.4.10.tar.gz
# tar -xf zookeeper-3.4.10.tar.gz -C /usr/local
# vi /etc/profile.d/zookeeper.sh
export ZOOKEEPER_HOME=/usr/local/zookeeper-3.4.10
export PATH=$ZOOKEEPER_HOME/bin:$PATH
# . /etc/profile.d/zookeeper.sh
# cd /usr/local/zookeeper-3.4.10/conf/
# cp zoo_sample.cfg zoo.cfg 

# vi zoo.cfg 
# The number of milliseconds of each tick
tickTime=2000　　心跳周期2000毫秒
# 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=/data/zookeeper　　数据目录
# the port at which the clients will connect
clientPort=2181　　客户端连接端口
# the maximum number of client connections.
# increase this if you need to handle more clients
#maxClientCnxns=60
server.1=node84:2888:3888
server.2=node85:2888:3888
server.3=node86:2888:3888

node84	node85	node86
# mkdir -p /data/zookeeper # echo 1 >>/data/zookeeper/myid	# mkdir -p /data/zookeeper # echo 2 >>/data/zookeeper/myid	# mkdir -p /data/zookeeper # echo 3 >>/data/zookeeper/myid
# cat /etc/profile.d/zookeeper.sh export ZOOKEEPER_HOME=/usr/local/zookeeper-3.4.10 export PATH=$ZOOKEEPER_HOME/bin:$PATH # . /etc/profile.d/zookeeper.sh

zookeeper集群模式配置（故障算法2n+1，即集群个数为奇数,集群生效条件为大于半数zkserver ok）
server.n=hostname:port1:port2
　　　　　#n必须是myid中的指定值,dataDir=/data/zookeeper下创建的myid文件指定
　　　　　#port1　　leader端口，作为leader时，供follower连接的端口
　　　　　#port2　　选举端口，选举leader时供其它fllower连接的端口
　　server.1=s1:2888:3888
　　server.2=s2:2888:3888
　　server.3=s3:2888:3888
zookeeper伪分布集群模式

zoo1.cnf	zoo2.cnf	zoo3.cnf
dataDir=/data/zookeeper/data1 server.1=localhost:2887:3887 server.2=localhost:2888:3888 server.3=localhost:2889:3889	dataDir=/data/zookeeper/data2 server.1=localhost:2887:3887 server.2=localhost:2888:3888 server.3=localhost:2889:3889	dataDir=/data/zookeeper/data2 server.1=localhost:2887:3887 server.2=localhost:2888:3888 server.3=localhost:2889:3889

node84	node85	node86
[root@node84 local]# zkServer.sh start ZooKeeper JMX enabled by default Using config: /usr/local/zookeeper-3.4.10/bin/../conf/zoo.cfg Starting zookeeper ... STARTED [root@node84 local]# zkServer.sh status ZooKeeper JMX enabled by default Using config: /usr/local/zookeeper-3.4.10/bin/../conf/zoo.cfg Error contacting service. It is probably not running. [root@node84 local]# zkServer.sh status ZooKeeper JMX enabled by default Using config: /usr/local/zookeeper-3.4.10/bin/../conf/zoo.cfg Mode: follower [root@node84 local]# jps 2130 QuorumPeerMain 2211 Jps	# zkServer.sh start ZooKeeper JMX enabled by default Using config: /usr/local/zookeeper-3.4.10/bin/../conf/zoo.cfg Starting zookeeper ... STARTED # zkServer.sh status ZooKeeper JMX enabled by default Using config: /usr/local/zookeeper-3.4.10/bin/../conf/zoo.cfg Mode: leader # jps 2177 Jps 2118 QuorumPeerMain	[root@node86 tools]# zkServer.sh start ZooKeeper JMX enabled by default Using config: /usr/local/zookeeper-3.4.10/bin/../conf/zoo.cfg Starting zookeeper ... STARTED [root@node86 tools]# jps 26834 QuorumPeerMain 26859 Jps
[root@node84 local]# ls /data/zookeeper/ myid  version-2  zookeeper_server.pid

 

nc命令使用
[root@node84 ~]# nc -l 1234　　启动监听
[root@node85 ~]# nc node84 1234　　连接
==>可以实现字符聊天

文件传送
[root@node84 ~]# nc -l 1234 > nctest　　启动监听，准备接受内容写入到nctest
[root@node85 ~]# nc node84 1234 </etc/hosts　　发送host文件内容

端口扫描
[root@node84 ~]# nc 192.168.0.85 -z 15-22 -v -w 10
　　-z 端口扫描 + 范围
　　-w 超时时间
　　-v 详细输出
nc: connect to 192.168.0.85 port 15 (tcp) failed: Connection refused
nc: connect to 192.168.0.85 port 16 (tcp) failed: Connection refused
nc: connect to 192.168.0.85 port 17 (tcp) failed: Connection refused
nc: connect to 192.168.0.85 port 18 (tcp) failed: Connection refused
nc: connect to 192.168.0.85 port 19 (tcp) failed: Connection refused
nc: connect to 192.168.0.85 port 20 (tcp) failed: Connection refused
nc: connect to 192.168.0.85 port 21 (tcp) failed: Connection refused
Connection to 192.168.0.85 22 port [tcp/ssh] succeeded!

[root@node84 ~]# nc 192.168.0.85 -z 2000-4000
Connection to 192.168.0.85 2181 port [tcp/eforward] succeeded!
Connection to 192.168.0.85 2888 port [tcp/spcsdlobby] succeeded!
Connection to 192.168.0.85 3888 port [tcp/ciphire-serv] succeeded!

 

[root@node83 ~]# echo conf | nc node84 2181　　获取配置信息（也可以# nc node84 2181后输入）
clientPort=2181
dataDir=/data/zookeeper/version-2
dataLogDir=/data/zookeeper/version-2
tickTime=2000
maxClientCnxns=60
minSessionTimeout=4000
maxSessionTimeout=40000
serverId=1
initLimit=10
syncLimit=5
electionAlg=3
electionPort=3888
quorumPort=2888
peerType=0

[root@node83 ~]# echo ruok | nc node84 2181
imok

[root@node83 ~]# echo envi | nc node84 2181　　获取环境信息
//其他
　　　　cons　　连接信息
　　　　dump　　未处理会话节点
　　　　reqs　　未处理请求
　　　　stat　　统计信息
　　　　wchs　　服务watch的详细信息
　　　　wchp　　列出指定路径下的服务器信息

 

[root@node83 ~]# zkCli.sh -server node84:2181
..........
..........
..........
WATCHER::

WatchedEvent state:SyncConnected type:None path:null

[zk: node84:2181(CONNECTED) 0] 等待输入

[zk: node84:2181(CONNECTED) 0] h　　输入h获取帮助
ZooKeeper -server host:port cmd args
        stat path [watch]
        set path data [version]
        ls path [watch]
        delquota [-n|-b] path
        ls2 path [watch]
        setAcl path acl
        setquota -n|-b val path
        history 
        redo cmdno
        printwatches on|off
        delete path [version]
        sync path
        listquota path
        rmr path
        get path [watch]
        create [-s] [-e] path data acl
        addauth scheme auth
        quit 
        getAcl path
        close 
        connect host:port

[zk: node84:2181(CONNECTED) 0] ls /
[zookeeper]
[zk: node84:2181(CONNECTED) 1] ls /zookeeper
[quota]
[zk: node84:2181(CONNECTED) 2] 

[zk: node84:2181(CONNECTED) 3] create /dirtest1 hello   
Created /dirtest1
[zk: node84:2181(CONNECTED) 4] ls /
[zookeeper, dirtest1]
[zk: node84:2181(CONNECTED) 6] ls /dirtest1
[]
[zk: node84:2181(CONNECTED) 7] get /dirtest1
hello
cZxid = 0x100000004
ctime = Tue Jun 06 02:25:18 CST 2017
mZxid = 0x100000004
mtime = Tue Jun 06 02:25:18 CST 2017
pZxid = 0x100000004
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 5
numChildren = 0

[zk: node84:2181(CONNECTED) 8] set /dirtest1 helloworld
cZxid = 0x100000004
ctime = Tue Jun 06 02:25:18 CST 2017
mZxid = 0x100000005
mtime = Tue Jun 06 02:27:53 CST 2017
pZxid = 0x100000004
cversion = 0
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 10
numChildren = 0

[zk: node84:2181(CONNECTED) 9] create /dirtest1/secdir shanhgai　　只能一层层创建
Created /dirtest1/secdir
[zk: node84:2181(CONNECTED) 10] ls /dirtest1
[secdir]
[zk: node84:2181(CONNECTED) 11] get /dirtest1/secdir
shanhgai
cZxid = 0x100000006
ctime = Tue Jun 06 02:29:32 CST 2017
mZxid = 0x100000006
mtime = Tue Jun 06 02:29:32 CST 2017
pZxid = 0x100000006
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 8
numChildren = 0

 

 

 

Simple API
One of the design goals of ZooKeeper is provide a very simple programming interface. As a result, it supports only these operations:

create 
　　creates a node at a location in the tree
delete 
　　deletes a node
exists 
　　tests if a node exists at a location
get data 
　　reads the data from a node
set data 
　　writes data to a node
get children 
　　retrieves a list of children of a node
sync 
　　waits for data to be propagated