访问Zookeeper
开启Zookeeper服务程序：
./zkServer.sh start
启动Zookeeper客户端进行访问：
./zkCli.sh
运行打印：
[root@VM-0-7-centos bin]# ./zkCli.sh
/usr/bin/java
Connecting to localhost:2181
2020-08-07 09:08:15,680 [myid:] - INFO [main:Environment@109] - Client environment:zookeeper.version=3.5.8-f439ca583e70862c3068a1f2a7d4d068eec33315, built on 05/04/2020 15:07 GMT
2020-08-07 09:08:15,683 [myid:] - INFO [main:Environment@109] - Client environment:host.name=VM-0-7-centos
2020-08-07 09:08:15,683 [myid:] - INFO [main:Environment@109] - Client environment:java.version=1.8.0_252
2020-08-07 09:08:15,687 [myid:] - INFO [main:Environment@109] - Client environment:java.vendor=Oracle Corporation
2020-08-07 09:08:15,687 [myid:] - INFO [main:Environment@109] - Client environment:java.home=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre
2020-08-07 09:08:15,687 [myid:] - INFO [main:Environment@109] - Client environment:java.class.path=/usr/local/zookeeper/bin/../zookeeper-server/target/classes:/usr/local/zookeeper/bin/../build/classes:/usr/local/zookeeper/bin/../zookeeper-server/target/lib/*.jar:/usr/local/zookeeper/bin/../build/lib/*.jar:/usr/local/zookeeper/bin/../lib/zookeeper-jute-3.5.8.jar:/usr/local/zookeeper/bin/../lib/zookeeper-3.5.8.jar:/usr/local/zookeeper/bin/../lib/slf4j-log4j12-1.7.25.jar:/usr/local/zookeeper/bin/../lib/slf4j-api-1.7.25.jar:/usr/local/zookeeper/bin/../lib/netty-transport-native-unix-common-4.1.48.Final.jar:/usr/local/zookeeper/bin/../lib/netty-transport-native-epoll-4.1.48.Final.jar:/usr/local/zookeeper/bin/../lib/netty-transport-4.1.48.Final.jar:/usr/local/zookeeper/bin/../lib/netty-resolver-4.1.48.Final.jar:/usr/local/zookeeper/bin/../lib/netty-handler-4.1.48.Final.jar:/usr/local/zookeeper/bin/../lib/netty-common-4.1.48.Final.jar:/usr/local/zookeeper/bin/../lib/netty-codec-4.1.48.Final.jar:/usr/local/zookeeper/bin/../lib/netty-buffer-4.1.48.Final.jar:/usr/local/zookeeper/bin/../lib/log4j-1.2.17.jar:/usr/local/zookeeper/bin/../lib/json-simple-1.1.1.jar:/usr/local/zookeeper/bin/../lib/jline-2.11.jar:/usr/local/zookeeper/bin/../lib/jetty-util-9.4.24.v20191120.jar:/usr/local/zookeeper/bin/../lib/jetty-servlet-9.4.24.v20191120.jar:/usr/local/zookeeper/bin/../lib/jetty-server-9.4.24.v20191120.jar:/usr/local/zookeeper/bin/../lib/jetty-security-9.4.24.v20191120.jar:/usr/local/zookeeper/bin/../lib/jetty-io-9.4.24.v20191120.jar:/usr/local/zookeeper/bin/../lib/jetty-http-9.4.24.v20191120.jar:/usr/local/zookeeper/bin/../lib/javax.servlet-api-3.1.0.jar:/usr/local/zookeeper/bin/../lib/jackson-databind-2.10.3.jar:/usr/local/zookeeper/bin/../lib/jackson-core-2.10.3.jar:/usr/local/zookeeper/bin/../lib/jackson-annotations-2.10.3.jar:/usr/local/zookeeper/bin/../lib/commons-cli-1.2.jar:/usr/local/zookeeper/bin/../lib/audience-annotations-0.5.0.jar:/usr/local/zookeeper/bin/../zookeeper-*.jar:/usr/local/zookeeper/bin/../zookeeper-server/src/main/resources/lib/*.jar:/usr/local/zookeeper/bin/../conf:
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:java.library.path=/usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:java.io.tmpdir=/tmp
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:java.compiler=<NA>
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:os.name=Linux
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:os.arch=amd64
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:os.version=3.10.0-1062.18.1.el7.x86_64
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:user.name=root
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:user.home=/root
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:user.dir=/usr/local/zookeeper/bin
2020-08-07 09:08:15,688 [myid:] - INFO [main:Environment@109] - Client environment:os.memory.free=23MB
2020-08-07 09:08:15,690 [myid:] - INFO [main:Environment@109] - Client environment:os.memory.max=247MB
2020-08-07 09:08:15,691 [myid:] - INFO [main:Environment@109] - Client environment:os.memory.total=29MB
2020-08-07 09:08:15,694 [myid:] - INFO [main:ZooKeeper@868] - Initiating client connection, connectString=localhost:2181 sessionTimeout=30000 watcher=org.apache.zookeeper.ZooKeeperMain$MyWatcher@484b61fc
2020-08-07 09:08:15,704 [myid:] - INFO [main:X509Util@79] - Setting -D jdk.tls.rejectClientInitiatedRenegotiation=true to disable client-initiated TLS renegotiation
2020-08-07 09:08:15,711 [myid:] - INFO [main:ClientCnxnSocket@237] - jute.maxbuffer value is 4194304 Bytes
2020-08-07 09:08:15,727 [myid:] - INFO [main:ClientCnxn@1653] - zookeeper.request.timeout value is 0. feature enabled=
2020-08-07 09:08:15,737 [myid:localhost:2181] - INFO [main-SendThread(localhost:2181):ClientCnxn$SendThread@1112] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:2181. Will not attempt to authenticate using SASL (unknown error)
Welcome to ZooKeeper!
JLine support is enabled
2020-08-07 09:08:15,876 [myid:localhost:2181] - INFO [main-SendThread(localhost:2181):ClientCnxn$SendThread@959] - Socket connection established, initiating session, client: /0:0:0:0:0:0:0:1:48090, server: localhost/0:0:0:0:0:0:0:1:2181
[zk: localhost:2181(CONNECTING) 0] 2020-08-07 09:08:15,920 [myid:localhost:2181] - INFO [main-SendThread(localhost:2181):ClientCnxn$SendThread@1394] - Session establishment complete on server localhost/0:0:0:0:0:0:0:1:2181, sessionid = 0x100048bdb4c0000, negotiated timeout = 30000
WATCHER::
输入quit回车退出zookeeper客户端：
WatchedEvent state:SyncConnected type:None path:null
quit
WATCHER::
WatchedEvent state:Closed type:None path:null
2020-08-07 09:08:23,890 [myid:] - INFO [main:ZooKeeper@1422] - Session: 0x100048bdb4c0000 closed
2020-08-07 09:08:23,891 [myid:] - INFO [main-EventThread:ClientCnxn$EventThread@524] - EventThread shut down for session: 0x100048bdb4c0000
创建节点：
语法：
create [-s] [-e] path data acl
参数说明：
-s表示顺序节点， -e表示临时节点 默认情况下，创建的是持久节点。 path是节点路径， data是节点数据， acl用来进行权限控制
案例：
create /sanguo luoguanzhong 创建一个持久节点目录为/sanguo 值为 luoguanzhong create -s /shuihu shinaian 创建一个持久顺序节点目录为/shuihu 值为 shinaian create -e /xiyou wuchengren 创建一个临时节点目录为/xiyou 值为 wuchengren create -e -s /honglou caoxueqing 创建一个临时顺序节点目录为/honglou 值为 caoxueqing
我的测试：
WATCHER::
WatchedEvent state:SyncConnected type:None path:null
[zk: localhost:2181(CONNECTED) 0] create -e /zkNode01 dzz
Created /zkNode01
[zk: localhost:2181(CONNECTED) 1]
查看节点内容：
使用get命令，获取zookeeper指定节点的内容和属性信息
[zk: localhost:2181(CONNECTED) 1] get /zkNode01
dzz
如果输入完整信息get
[zk: localhost:2181(CONNECTED) 2] get /zkNode01 dzz
'get path [watch]' has been deprecated. Please use 'get [-s] [-w] path' instead.
ZK提示此命令已经过时不适用了，要求使用 -s & -w 参数进行获取
[zk: localhost:2181(CONNECTED) 4] get -s -w /zkNode01
dzz
cZxid = 0x4
ctime = Fri Aug 07 09:16:10 CST 2020
mZxid = 0x4
mtime = Fri Aug 07 09:16:10 CST 2020
pZxid = 0x4
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x100048bdb4c0001
dataLength = 3
numChildren = 0
也可以使用stat命名查看：
stat /zkNode01
若是需要查看子节点：
ls / 查看根节点下的所有子节点 ls 指定的节点 查看该节点下的所有子节点
查看根的子节点们：
[zk: localhost:2181(CONNECTED) 5] ls /
[zkNode01, zookeeper]
除了我们刚刚创建zkNode01，发现还有一个节点，名称就为zookeeper
查看这个节点的信息：
[zk: localhost:2181(CONNECTED) 6] get -s -w /zookeeper
cZxid = 0x0
ctime = Thu Jan 01 08:00:00 CST 1970
mZxid = 0x0
mtime = Thu Jan 01 08:00:00 CST 1970
pZxid = 0x0
cversion = -2
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 0
numChildren = 2
更新修改节点内容：
使用set命令，更新节点内容。
语法：
set path data
其中的data就是要更新的新内容。
其实更新的是节点的data
[zk: localhost:2181(CONNECTED) 31] get -s -w /zkNode01
123
cZxid = 0x4
ctime = Fri Aug 07 09:16:10 CST 2020
mZxid = 0x8
mtime = Fri Aug 07 09:39:15 CST 2020
pZxid = 0x4
cversion = 0
dataVersion = 4
aclVersion = 0
ephemeralOwner = 0x100048bdb4c0001
dataLength = 3
numChildren = 0
每一次更新 dataVersion都会追加修改的记录次数
删除节点：
首先节点结构是一个树状结构，也就是说一个节点下面会有N个子节点，也可能没有
如果我们某一个节点进行删除，那么也就代表着该节点下面的后代节点都将被删除，
Zookeeper在我们执行删除节点的操作时会判断有无后代节点，如果有是不允许删除该节点的
例如这样：
[zk: localhost:2181(CONNECTED) 31] delete /someNode
Node not empty : /someNode
我们刚刚创建的节点下面并没有其他子节点，所有删除正常：
[zk: localhost:2181(CONNECTED) 32] delete /zkNode01
WATCHER::
WatchedEvent state:SyncConnected type:NodeDeleted path:/zkNode01
但是如果需要删除该节点和所有子节点操作的话，是使用此命令：
rmr 节点路径
监控节点：
我们再开启一个XSHELL访问：
在下面客户端创建一个新节点，并且 在上面的客户端中获取节点信息并且监视节点
当节点的数据进行修改，上面的客户端就会监听到改动：
