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每日英文
The fact is that the world is out of everyone's expectation. But some learn to forget, but others insist.
事实上,这个世界不会符合所有人的梦想。只是有人学会遗忘,有人却坚持。
每日掏心话
在这世界上,什么假货都会被揭穿,只有假爱最难识破。有人可以给你浪漫,却给不了真实。
责编:乐乐 | 来自:blog.csdn.net/xuan_lu/
往日回顾:
正文
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
节点属性
1. 启动ZK服务: ./zkServer.sh start
2. 查看ZK服务状态: ./zkServer.sh status
3. 停止ZK服务: ./zkServer.sh stop
4. 重启ZK服务: ./zkServer.sh restart
5. 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
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`
help命令
- `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
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 args
新增、查询节点
addauth scheme auth
close
config [-c] [-w] [-s]
connect host:port
create [-s] [-e] [-c] [-t ttl] path [data] [acl]
delete [-v version] path
deleteall path
delquota [-n|-b] path
get [-s] [-w] path
getAcl [-s] path
history
listquota path
ls [-s] [-w] [-R] path
ls2 path [watch]
printwatches on|off
quit
reconfig [-s] [-v version] [[-file path] | [-members serverID=host:port1:port2;port3[,...]*]] | [-add serverId=host:port1:port2;port3[,...]]* [-remove serverId[,...]*]
redo cmdno
removewatches path [-c|-d|-a] [-l]
rmr path
set [-s] [-v version] path data
setAcl [-s] [-v version] [-R] path acl
setquota -n|-b val path
stat [-w] path
sync path
Command not found: Command not found help
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 /node1
123
cZxid = 0x43
ctime = Wed Jul 29 21:27:31 CST 2020
mZxid = 0x43
mtime = Wed Jul 29 21:27:31 CST 2020
pZxid = 0x43
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 3
numChildren = 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 /seqNode10000000011
seq1
cZxid = 0x44
ctime = Wed Jul 29 21:28:25 CST 2020
mZxid = 0x44
mtime = Wed Jul 29 21:28:25 CST 2020
pZxid = 0x44
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 4
numChildren = 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 /tmpNode10000000012
tmp
cZxid = 0x45
ctime = Wed Jul 29 21:35:28 CST 2020
mZxid = 0x45
mtime = Wed Jul 29 21:35:28 CST 2020
pZxid = 0x45
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x10029ab39130008
dataLength = 3
numChildren = 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 /node1
456
[zk: localhost:2181(CONNECTED) 15] set -v 0 /node1 "234"
WATCHER::
WatchedEvent state:SyncConnected type:NodeDataChanged path:/node1
删除节点
[zk: localhost:2181(CONNECTED) 16] get -w /node1
234
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 /node1
org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /node1
[zk: localhost:2181(CONNECTED) 4] create /node1 "node1"
Created /node1
[zk: localhost:2181(CONNECTED) 5] create /node1/node11 "node11"
Created /node1/node11
//使用delete删除存在子节点的节点,删除失败
[zk: localhost:2181(CONNECTED) 6] delete /node1
Node not empty: /node1
[zk: localhost:2181(CONNECTED) 7] get -s /node1
node1
cZxid = 0x4f
ctime = Wed Jul 29 21:53:37 CST 2020
mZxid = 0x4f
mtime = Wed Jul 29 21:53:37 CST 2020
pZxid = 0x50
cversion = 1
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 5
numChildren = 1
[zk: localhost:2181(CONNECTED) 8] deleteall /node1
[zk: localhost:2181(CONNECTED) 9] get /node1
org.apache.zookeeper.KeeperException$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 /node1
查看子节点列表
The command 'rmr' has been deprecated. Please use 'deleteall' instead.
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 = 0x0
ctime = Thu Jan 01 08:00:00 CST 1970
mZxid = 0x0
mtime = Thu Jan 01 08:00:00 CST 1970
pZxid = 0x53
cversion = 22
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 0
numChildren = 6
[zk: localhost:2181(CONNECTED) 21] create /node1 "node1"
查看节点状态
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]
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 /node1
监听器
cZxid = 0x55
ctime = Wed Jul 29 22:05:16 CST 2020
mZxid = 0x55
mtime = Wed Jul 29 22:05:16 CST 2020
pZxid = 0x56
cversion = 1
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 5
numChildren = 1
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 /node1
node1
//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:
图片
[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:
权限模式(
scheme
):授权的策略授权对象(
id
):授权的对象权限(
permission
):授予的权限权限模式| 方案 | 描述 | | --- | --- | | world | 只有一个用户:
anyone
,代表登录zookeeper
所有人(默认) | | ip | 对客户端使用IP地址认证 | | auth | 使用已添加认证的用户认证 | | digest | 使用"用户名:密码"方式认证 |
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
权限 ACL简写 描述 create c 可以创建子结点 delete d 可以删除子结点(仅下一级结点) read r 可以读取结点数据以及显示子结点列表 write w 可以设置结点数据 admin a 可以设置结点访问控制权限列表
授权的相关命令
命令 使用方式 描述 getAcl getAcl 读取ACL权限 setAcl setAcl 设置ACL权限 addauth addauth 添加认证用户
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 /ipNode
ipNode
cZxid = 0x65
ctime = Wed Jul 29 23:22:23 CST 2020
mZxid = 0x65
mtime = Wed Jul 29 23:22:23 CST 2020
pZxid = 0x65
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 6
numChildren = 0
[zk: localhost:2181(CONNECTED) 10] setAcl /ipNode ip:192.168.16.81:ra
[zk: localhost:2181(CONNECTED) 11] get -s /ipNode
org.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /ipNode
auth模式:命令:
addauth digest :
****setAcl auth::
//认证用户
[zk: localhost:2181(CONNECTED) 36] addauth digest qxy:123456
[zk: localhost:2181(CONNECTED) 37] get -s /node1
set node1
cZxid = 0x55
ctime = Wed Jul 29 22:05:16 CST 2020
mZxid = 0x58
mtime = Wed Jul 29 22:31:29 CST 2020
pZxid = 0x5c
cversion = 2
dataVersion = 1
aclVersion = 2
ephemeralOwner = 0x0
dataLength = 9
numChildren = 2
//设置认证用户
[zk: localhost:2181(CONNECTED) 38] setAcl /node1 auth:qxy:cdrwa
//退出,重新进入
[zk: localhost:2181(CONNECTED) 39] quit
WATCHER::
WatchedEvent state:Closed type:None path:null
2020-07-29 22:58:56,574 [myid:] - INFO [main:ZooKeeper@1422] - Session: 0x10029ab39130009 closed
2020-07-29 22:58:56,574 [myid:] - INFO [main-EventThread:ClientCnxn$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 /node1
org.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /node1
//认证用户,注意此处密码错误,不会提示错误,但是无法访问节点
[zk: localhost:2181(CONNECTED) 1] addauth digest qxy:123456
[zk: localhost:2181(CONNECTED) 2] get -s /node1
set node1
cZxid = 0x55
ctime = Wed Jul 29 22:05:16 CST 2020
mZxid = 0x58
mtime = Wed Jul 29 22:31:29 CST 2020
pZxid = 0x5c
cversion = 2
dataVersion = 1
aclVersion = 3
ephemeralOwner = 0x0
dataLength = 9
numChildren = 2
Digest模式:命令:**
setAcl digest:::
**密码是经过SHA1
以及BASE64
处理的密文,在shell 中可以通过以下命令计算:
echo -n : | openssl dgst -binary -sha1 | openssl base64
建立新的窗口,计算密码
[root@izbp14najjyuhkvm4qbic7z bin]# echo -n qxy:123456 | openssl dgst -binary -sha1 | openssl base64
hDF4uLZvMJqOX2ekKFa6kSz9HNo=
实战:
[zk: localhost:2181(CONNECTED) 5] create /digestNode "digestNode"
Created /digestNode
[zk: localhost:2181(CONNECTED) 2] setAcl /digestNode digest:qxy:hDF4uLZvMJqOX2ekKFa6kSz9HNo=:cdrwa
[zk: localhost:2181(CONNECTED) 3] get /digestNode
org.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /digestNode
[zk: localhost:2181(CONNECTED) 2] setAcl /digestNode digest:qxy:hDF4uLZvMJqOX2ekKFa6kSz9HNo=:cdrwa
[zk: localhost:2181(CONNECTED) 3] get /digestNode
org.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /digestNode
[zk: localhost:2181(CONNECTED) 4] getAcl /digestNode
Authentication 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 /digestNode
digestNode
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