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首先说明一下环境，溪源使用zookeeper版本为3.5.10；由于版本不同，命令语法略有差异，提前说明一下，但是基本原理一致，大家可以通过help命令查看自己当前版本的命令语法。

客户端、服务器命令

切换至zookeeper安装目录下的bin目录输入以下命令启动服务器或者客户端1. 启动ZK服务: ./zkServer.sh start2. 查看ZK服务状态: ./zkServer.sh status3. 停止ZK服务: ./zkServer.sh stop4. 重启ZK服务: ./zkServer.sh restart5. 连接内部客户端: ./zkCli.sh或者./zkCli.sh -server 127.0.0.1(指定连接服务器IP):2181

节点属性

学习zookeeper常用命令之前先介绍一下节点属性的含义。

-`cZxid`：当前数据结点创建时的事务ID——针对于`zookeeper`数据结点的管理：我们对结点数据的一些写操作都会导致`zookeeper`自动地为我们去开启一个事务，并且自动地去为每一个事务维护一个事务`ID`- `ctime`：当前数据结点创建时的时间- `mZxid`：当前数据结点最后一次更新时的事务ID- `mtime`：当前数据结点最后一次更新时的时间- `pZxid`：当前数据节点最后一次修改**其**子节点**更改的`zxid`。修改指(增加子节点、删除子节点)，并不指其子节点的数据发生改变；- `cversion`：当前数据节点对应**子结点**的更改次数- `dataVersion`：当前结点数据的发生更改的次数- `aclVersion`：当前结点的ACL更改次数——类似`linux`的权限列表，维护的是当前结点的权限列表被修改的次数- `ephemeralOwner`：如果结点是临时结点，则表示创建该结点的会话的`SessionID`；如果是持久结点，该属性值为0- `dataLength`：当前节点的数据内容长度- `numChildren`：当前数据结点的子结点个数

help命令

zookeeper基本常用命令通过help查看，遇到错误命令可以直接查询语法。

ZooKeeper -server host:port cmd argsaddauth scheme authclose config [-c] [-w] [-s]connect host:portcreate [-s] [-e] [-c] [-t ttl] path [data] [acl]delete [-v version] pathdeleteall pathdelquota [-n|-b] pathget [-s] [-w] pathgetAcl [-s] pathhistory listquota pathls [-s] [-w] [-R] pathls2 path [watch]printwatches on|offquit reconfig [-s] [-v version] [[-file path] | [-members serverID=host:port1:port2;port3[,...]*]] | [-add serverId=host:port1:port2;port3[,...]]* [-remove serverId[,...]*]redo cmdnoremovewatches path [-c|-d|-a] [-l]rmr pathset [-s] [-v version] path datasetAcl [-s] [-v version] [-R] path aclsetquota -n|-b val pathstat [-w] pathsync pathCommand not found: Command not found help12345678910111213141516171819202122232425262728

新增、查询节点

• 新增命令：create [-s] [-e] path data
  其中 -s 为有序结点，-e 临时结点(默认是持久结点)
• 查询命令：get [-s] [-w] path
  -s 查看节点所有信息:数据信息+节点属性值
  -w 查看节点数据信息
• 实战

//创建持久化节点node1[zk: localhost:2181(CONNECTED) 0] create /node1 "123"Created /node1//查看node1节点属性[zk: localhost:2181(CONNECTED) 1] get -s /node1123cZxid = 0x43ctime = Wed Jul 29 21:27:31 CST 2020mZxid = 0x43mtime = Wed Jul 29 21:27:31 CST 2020pZxid = 0x43cversion = 0dataVersion = 0aclVersion = 0ephemeralOwner = 0x0dataLength = 3numChildren = 0//创建有序持久化节点[zk: localhost:2181(CONNECTED) 2] create -s /seqNode1 "seq1"Created /seqNode10000000011//查看有序持久化节点信息[zk: localhost:2181(CONNECTED) 3] get -s /seqNode10000000011seq1cZxid = 0x44ctime = Wed Jul 29 21:28:25 CST 2020mZxid = 0x44mtime = Wed Jul 29 21:28:25 CST 2020pZxid = 0x44cversion = 0dataVersion = 0aclVersion = 0ephemeralOwner = 0x0dataLength = 4numChildren = 0//创建临时节点[zk: localhost:2181(CONNECTED) 4] create -s -e /tmpNode1 "tmp"Created /tmpNode10000000012[zk: localhost:2181(CONNECTED) 5] get -s /tmpNode10000000012tmpcZxid = 0x45ctime = Wed Jul 29 21:35:28 CST 2020mZxid = 0x45mtime = Wed Jul 29 21:35:28 CST 2020pZxid = 0x45cversion = 0dataVersion = 0aclVersion = 0ephemeralOwner = 0x10029ab39130008dataLength = 3numChildren = 0

修改节点

• 命令： set [-s] [-v version] path data
  可以直接进行修改;也可以选择使用版本号
  -v + 版本号，类似乐观锁原理；

[zk: localhost:2181(CONNECTED) 13] set /node1 "456"[zk: localhost:2181(CONNECTED) 14] get -w /node1456[zk: localhost:2181(CONNECTED) 15] set -v 0 /node1 "234"WATCHER::WatchedEvent state:SyncConnected type:NodeDataChanged path:/node1[zk: localhost:2181(CONNECTED) 16] get -w /node1234

删除节点

• 命令：

delete [-v version] path:可以直接删除，也可以指定版本号删除，此命令只能删除单个节点，如果存在子节点，则需要依次删除子节点

deleteall path：直接删除指定的所有节点

[zk: localhost:2181(CONNECTED) 0] delete /node1[zk: localhost:2181(CONNECTED) 1] get -s /node1org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /node1[zk: localhost:2181(CONNECTED) 4] create /node1 "node1"Created /node1[zk: localhost:2181(CONNECTED) 5] create /node1/node11 "node11"Created /node1/node11//使用delete删除存在子节点的节点，删除失败[zk: localhost:2181(CONNECTED) 6] delete /node1Node not empty: /node1[zk: localhost:2181(CONNECTED) 7] get -s /node1node1cZxid = 0x4fctime = Wed Jul 29 21:53:37 CST 2020mZxid = 0x4fmtime = Wed Jul 29 21:53:37 CST 2020pZxid = 0x50cversion = 1dataVersion = 0aclVersion = 0ephemeralOwner = 0x0dataLength = 5numChildren = 1[zk: localhost:2181(CONNECTED) 8] deleteall /node1[zk: localhost:2181(CONNECTED) 9] get /node1org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /node1

注意：删除存在子节点时，命令不要再使用rmr，此命令已经无效。

[zk: localhost:2181(CONNECTED) 17] rmr /node1The command 'rmr' has been deprecated. Please use 'deleteall' instead.

查看子节点列表

• 命令：

ls [-s] [-w] [-R] path:

ls2 path [watch]

[zk: localhost:2181(CONNECTED) 19] ls /[a0000000001, b0000000002, c, hadoop, seqNode10000000011, zookeeper][zk: localhost:2181(CONNECTED) 20] ls -s /[a0000000001, b0000000002, c, hadoop, seqNode10000000011, zookeeper]cZxid = 0x0ctime = Thu Jan 01 08:00:00 CST 1970mZxid = 0x0mtime = Thu Jan 01 08:00:00 CST 1970pZxid = 0x53cversion = 22dataVersion = 0aclVersion = 0ephemeralOwner = 0x0dataLength = 0numChildren = 6[zk: localhost:2181(CONNECTED) 21] create /node1 "node1"Created /node1//当前节点下没有子节点，返回空数组[zk: localhost:2181(CONNECTED) 22] ls /node1[][zk: localhost:2181(CONNECTED) 23] create /node1/node11 "node11"Created /node1/node11[zk: localhost:2181(CONNECTED) 24] ls /node1[node11]

查看节点状态

使用stat命令查看节点状态，与get命令的区别是此命令不返回数据信息；

[zk: localhost:2181(CONNECTED) 25] stat /node1cZxid = 0x55ctime = Wed Jul 29 22:05:16 CST 2020mZxid = 0x55mtime = Wed Jul 29 22:05:16 CST 2020pZxid = 0x56cversion = 1dataVersion = 0aclVersion = 0ephemeralOwner = 0x0dataLength = 5numChildren = 1

监听器

特殊说明get path [watch]命令已被废弃：

[zk: localhost:2181(CONNECTED) 27] get /node1 watch'get path [watch]' has been deprecated. Please use 'get [-s] [-w] path' instead.node1

使用 get [-s] [-w] path注册的监听器能够在结点内容发生改变的时候，向客户端发出通知。需要注意的是zookeeper的触发器是一次性的(One-time trigger)，即触发一次后就会立即失效。

//一个窗口监听，新打开一个窗口修改节点数据[zk: localhost:2181(CONNECTED) 29] get -w /node1node1//收到修改信息[zk: localhost:2181(CONNECTED) 30] WATCHER::WatchedEvent state:SyncConnected type:NodeDataChanged path:/node1//另一个窗口修改节点：[zk: localhost:2181(CONNECTED) 0] set /node1 "set node1"

权限控制

zookeeper类似文件系统，client可以创建结点、更新结点、删除结点，那么如何做到结点的权限控制呢？
zookeeper的 access control list 访问控制列表可以做到这一点。
acl权限控制，使用scheme：id：permission来标识，主要涵盖3个方面：

1. 权限模式(scheme)：授权的策略
2. 授权对象(id)：授权的对象
3. 权限(permission)：授予的权限权限模式

授权对象

• 给谁授予权限
• 授权对象ID是指，权限赋予的实体，例如：IP地址或用户

权限

• create、delete、read、writer、admin也就是 增、删、查、改、管理权限，这5种权限简写为 c d r w a，注意：
  这五种权限中，有的权限并不是对结点自身操作的例如：delete是指对子结点的删除权限。
  可以试图删除父结点，但是子结点必须删除干净，所以delete的权限也是很有用的

授权的相关命令

• world模式:

[zk: localhost:2181(CONNECTED) 31] getAcl /node1'world,'anyone: cdrwa[zk: localhost:2181(CONNECTED) 32] setAcl /node1 world:anyone:drwa[zk: localhost:2181(CONNECTED) 33] create /node1/node2 "node2"Authentication is not valid : /node1/node2[zk: localhost:2181(CONNECTED) 34] setAcl /node1 world:anyone:cdrwa[zk: localhost:2181(CONNECTED) 35] create /node1/node2 "node2"Created /node1/node2

• IP模式：
  需要两台虚拟机一起授权的话需要用逗号将授权列表隔开：setAcl /ipNode ip:192.168.103.133:cdrwa,ip:192.168.103.132:cdrwa

[zk: localhost:2181(CONNECTED) 8] create /ipNode "ipNode"Created /ipNode[zk: localhost:2181(CONNECTED) 9] get -s /ipNodeipNodecZxid = 0x65ctime = Wed Jul 29 23:22:23 CST 2020mZxid = 0x65mtime = Wed Jul 29 23:22:23 CST 2020pZxid = 0x65cversion = 0dataVersion = 0aclVersion = 0ephemeralOwner = 0x0dataLength = 6numChildren = 0[zk: localhost:2181(CONNECTED) 10] setAcl /ipNode ip:192.168.16.81:ra[zk: localhost:2181(CONNECTED) 11] get -s /ipNodeorg.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /ipNode

• auth模式：
  命令：addauth digest :setAcl auth::

//认证用户[zk: localhost:2181(CONNECTED) 36] addauth digest qxy:123456[zk: localhost:2181(CONNECTED) 37] get -s /node1set node1cZxid = 0x55ctime = Wed Jul 29 22:05:16 CST 2020mZxid = 0x58mtime = Wed Jul 29 22:31:29 CST 2020pZxid = 0x5ccversion = 2dataVersion = 1aclVersion = 2ephemeralOwner = 0x0dataLength = 9numChildren = 2//设置认证用户[zk: localhost:2181(CONNECTED) 38] setAcl /node1 auth:qxy:cdrwa//退出，重新进入[zk: localhost:2181(CONNECTED) 39] quitWATCHER::WatchedEvent state:Closed type:None path:null2020-07-29 22:58:56,574 [myid:] - INFO  [main:ZooKeeper@1422] - Session: 0x10029ab39130009 closed2020-07-29 22:58:56,574 [myid:] - INFO  [main-EventThread:ClientCnxn$EventThread@524] - EventThread shut down for session: 0x10029ab39130009//未用户认证，无法获取节点信息[zk: localhost:2181(CONNECTED) 0] get -s /node1org.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /node1//认证用户，注意此处密码错误，不会提示错误，但是无法访问节点[zk: localhost:2181(CONNECTED) 1] addauth digest qxy:123456[zk: localhost:2181(CONNECTED) 2] get -s /node1set node1cZxid = 0x55ctime = Wed Jul 29 22:05:16 CST 2020mZxid = 0x58mtime = Wed Jul 29 22:31:29 CST 2020pZxid = 0x5ccversion = 2dataVersion = 1aclVersion = 3ephemeralOwner = 0x0dataLength = 9numChildren = 2

• Digest模式：
  命令：setAcl digest:::
  密码是经过SHA1以及BASE64处理的密文，在shell 中可以通过以下命令计算：

 echo -n : | openssl dgst -binary -sha1 | openssl base64

建立新的窗口，计算密码

[root@izbp14najjyuhkvm4qbic7z bin]# echo -n qxy:123456 | openssl dgst -binary -sha1 | openssl base64hDF4uLZvMJqOX2ekKFa6kSz9HNo=

实战：

[zk: localhost:2181(CONNECTED) 5] create /digestNode "digestNode"Created /digestNode[zk: localhost:2181(CONNECTED) 2] setAcl /digestNode digest:qxy:hDF4uLZvMJqOX2ekKFa6kSz9HNo=:cdrwa[zk: localhost:2181(CONNECTED) 3] get /digestNodeorg.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /digestNode[zk: localhost:2181(CONNECTED) 2] setAcl /digestNode digest:qxy:hDF4uLZvMJqOX2ekKFa6kSz9HNo=:cdrwa[zk: localhost:2181(CONNECTED) 3] get /digestNodeorg.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /digestNode[zk: localhost:2181(CONNECTED) 4] getAcl /digestNodeAuthentication is not valid : /digestNode[zk: localhost:2181(CONNECTED) 5] addauth digest qxy:123456[zk: localhost:2181(CONNECTED) 6] getAcl /digestNode'digest,'qxy:hDF4uLZvMJqOX2ekKFa6kSz9HNo=: cdrwa[zk: localhost:2181(CONNECTED) 7] get /digestNodedigestNode

作者：溪~源

原文链接：https://blog.csdn.net/xuan_lu/article/details/107675047