轻量级分布式协调工具Etcd介绍和使用

柔光的暖阳◎ 2024-04-07 10:32 44阅读 0赞

## 1 Etcd介绍 ##

Etcd是CoreOS基于Raft协议开发的分布式key-value存储，可用于服务发现、共享配置以及一致性保障（如数据库选主、分布式锁等）。

### 1.1 etcd特点 ###

简单：curl可访问的用户的API（HTTP + JSON）  
安全：可选的SSL客户端证书认证  
快速：单实例每秒1000次写操作  
可靠：使用Raft算法保证一致性

### 1.2 etcd功能 ###

基本的key-value存储  
监听机制  
key的过期及续约机制， 用于监控和服务发现  
原子Compare And Swap和Compare And Delete, 用于分布式锁和leader选举

### 1.3 etcd写流程 ###

![在这里插入图片描述][3f4829d41205452d89f068013a5d31d6.png_pic_center]  
① 当客户端对etcd发起请求的时候，如果etcd不是leader的状态而是follower，follower则会将请求转发leader; 如果是leader后， 会对其进行预检查，检查（配额、限速、鉴权【判断请求是否合法】、包大小【需要小于1.5M，过大则会拒绝】）。  
② 如果请求本身是合法的，会将请求转发给KVServer处理。  
③ KVserver一致性模块进行数据处理，一致性模块是基于raft协议实现的，这时候的数据本身是处于unstable状态。  
④ 当leader该数据处理unstable状态后，会通过rpc通知其他follower也来同步该数据，并且leader本身会在数据同步到日志模块【wal日志， wal日志通过fsync落盘到磁盘中】。而其他follow在同步该数据的时候，本身完成的是步骤3和数据同步到日志模块，follower一致性模块数据变成commited状态，当完成了这些后通过上次rpc返回响应体给leader。  
⑤ leader在收到了超过半数集群本身确认后，更新MatchIndex, 一致性模块中数据本身由unstable变化成commited状态。这时候通过MVCC模块【treeIndex和BoltDB开源组件组成】进行状态机的写入，将数据同步到treeIndex【会更新modified版本\[当前版本号\]， generations信息\[创建的版本，当前版本数，过往的所有版本号\]】。再通过BoltDB落盘到磁盘中。这时候一致性模块数据由commited变化为applied状态。【在这里如果没有要求数据强一致性，弱一致性的话，那么数据在commited状态就认为数据已经同步完成了】。  
⑥ 再通过heatbeat将数据同步到follower中MVCC模块中。最终完成数据的一致性。如下图所示。 【如果follower比leader落后好几个版本，leader会通过headbeat带到follower进行同步】。

![在这里插入图片描述][173c917936fc48edb0fc385c884c7405.png_pic_center]

## 2 etcd安装部署 ##

### 2.1 单机版 ###

#### 2.1.1 下载安装包 ####

https://github.com/etcd-io/etcd/releases/tag/v3.5.4

#### 2.1.2 解压并运行 ####

tar -zxvf etcd-v3.5.4-linux-amd64.tar.gz

./etcd

#### 2.1.3 验证 ####

查看信息

./etcdctl member list --write-out=table

![在这里插入图片描述][462de3646eea457383b474145aaa74af.png]  
插入数据

./etcdctl --endpoints=localhost:2379 put chen perfect

![在这里插入图片描述][195bc1be21634918b610ce187d2a7d92.png]  
查看插入的数据

./etcdctl --endpoints=localhost:2379 get chen

![在这里插入图片描述][534bb13cc17b48e4a8fc3bb9d1b100e5.png]

### 2.2 集群部署 ###

#### 2.2.1 环境准备 ####

<table> 
 <thead> 
  <tr> 
   <th>主机</th> 
   <th>ip</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>linux1</td> 
   <td>192.168.159.200</td> 
  </tr> 
  <tr> 
   <td>linux2</td> 
   <td>192.168.159.201</td> 
  </tr> 
  <tr> 
   <td>linux3</td> 
   <td>192.168.159.202</td> 
  </tr> 
 </tbody> 
</table>

#### 2.2.2 编写配置文件 ####

在/root/software/etcd-v3.5.4-linux-amd64目录下新增conf目录，并在conf目录下新增etcd-conf.yml配置文件

# 节点名字
    name: linux1
    # 数据存储目录
    data-dir: /root/etcd/etcd-v3.5.4-linux-amd64/data
    # 该节点与客户端通信时监听的地址列表
    listen-client-urls: http://192.168.233.61:2379
    # 广播给集群中其他成员自己的客户端地址列表
    advertise-client-urls: http://192.168.233.61:2379
    # 该节点与其他节点通信时所监听的地址列表，多个地址使用逗号隔开，其格式可以划分为scheme://IP:PORT，这里的scheme可以是http、https
    listen-peer-urls: http://192.168.233.61:2380
    # 该成员节点在整个集群中的通信地址列表，这个地址用来传输集群数据的地址。因此这个地址必须是可以连接集群中所有的成员的。
    initial-advertise-peer-urls: http://192.168.233.61:2380
    # 启动集群使, 使用静态连接方法, 定义每个 member 主机名 endpoint
    initial-cluster: linux1=http://192.168.233.61:2380,linux2=http://192.168.233.62:2380,linux3=http://192.168.233.63:2380
    # 用于标记集群唯一性的 token，每个节点要一样
    initial-cluster-token: etcd-cluster-token
    # 初始化集群状态，new表示新建
    initial-cluster-state: new

linux1配置文件内容如下：

name: linux1
    data-dir: /root/software/etcd-v3.5.4-linux-amd64/data
    listen-client-urls: http://192.168.159.200:2379
    advertise-client-urls: http://192.168.159.200:2379
    listen-peer-urls: http://192.168.159.200:2380
    initial-advertise-peer-urls: http://192.168.159.200:2380
    initial-cluster: linux1=http://192.168.159.200:2380,linux2=http://192.168.159.201:2380,linux3=http://192.168.159.202:2380
    initial-cluster-token: etcd-cluster-token
    initial-cluster-state: new

linux2配置文件内容如下：

name: linux2
    data-dir: /root/software/etcd-v3.5.4-linux-amd64/data
    listen-client-urls: http://192.168.159.201:2379
    advertise-client-urls: http://192.168.159.201:2379
    listen-peer-urls: http://192.168.159.201:2380
    initial-advertise-peer-urls: http://192.168.159.201:2380
    initial-cluster: linux1=http://192.168.159.200:2380,linux2=http://192.168.159.201:2380,linux3=http://192.168.159.202:2380
    initial-cluster-token: etcd-cluster-token
    initial-cluster-state: new

linux3配置文件内容如下：

name: linux3
    data-dir: /root/software/etcd-v3.5.4-linux-amd64/data
    listen-client-urls: http://192.168.159.202:2379
    advertise-client-urls: http://192.168.159.202:2379
    listen-peer-urls: http://192.168.159.202:2380
    initial-advertise-peer-urls: http://192.168.159.202:2380
    initial-cluster: linux1=http://192.168.159.200:2380,linux2=http://192.168.159.201:2380,linux3=http://192.168.159.202:2380
    initial-cluster-token: etcd-cluster-token
    initial-cluster-state: new

#### 2.2.3 启动etcd集群 ####

在每个节点执行如下命令

./etcd --config-file /root/software/etcd-v3.5.4-linux-amd64/conf/etcd-conf.yml

#### 2.2.4 查看集群成员信息 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 member list --write-out=table

![在这里插入图片描述][39197ad618314d219ebfef06038a65e2.png]

#### 2.2.5 查看集群状态 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 endpoint status --write-out=table

![在这里插入图片描述][7380d9357ca54352b55dbea9d4acae63.png]

#### 2.2.6 查看集群健康信息 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 endpoint health --write-out=table

![在这里插入图片描述][9987651976f04209b5ab91982f02a6c0.png]

## 3 etcd集群减容与缩容 ##

### 3.1 减容 ###

#### 3.1.1 插入数据 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 put k1 v1

查看是否插入成功

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379  get k1

![在这里插入图片描述][7c2219f0114b4796b0ba328812a3b3f1.png]

### 3.1.2 执行减容 ###

# 查看减容节点的MEMBER_ID
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 member list --write-out=table
    # 删除MEMBER_ID
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 member remove ${MEMBER_ID}

![在这里插入图片描述][4f4460f4c12743dfaa99ddb180f71ba8.png]  
查看集群成员状态

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379  endpoint status --write-out=table

![在这里插入图片描述][edc1bd0bb2db4581921f76df65d99583.png]  
查看集群健康状态

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379  endpoint health --write-out=table

![在这里插入图片描述][27a307c502e146ceb0048b5bc32fbdc7.png]

#### 3.1.3 数据验证 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379  get k1

![在这里插入图片描述][a2a3823c36c74a28abee91e598867327.png]

### 3.2 集群扩容 ###

#### 3.2.1 扩容节点编写配置文件 ####

注意：–initial-cluster-state existing

#### 3.2.2 执行扩容操作 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379 member add linux3 --peer-urls=http://192.168.159.202:2380

![在这里插入图片描述][01d70df990154373bfcf746bad5b8182.png]

#### 3.2.3 扩容节点启动etcd服务 ####

./etcd --config-file /root/software/etcd-v3.5.4-linux-amd64/conf/etcd-conf.yml

#### 3.2.4 查看集群成员信息 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 member list --write-out=table

注意：减容后的202节点，重新扩容回集群，需要删除202节点上之前的节点存储目录。

#### 3.2.5 查看集群集群状态和健康信息 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 endpoint status --write-out=table

![在这里插入图片描述][c7c60d6167074fae88d85b4b5b8306a5.png]

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 endpoint health --write-out=table

![在这里插入图片描述][3a1c7849d3534fb1b1c0209a27d51a37.png]

#### 3.2.6 数据验证 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get k1

![在这里插入图片描述][a763381211c547ba8e655acf48556e42.png]

## 4 数据备份和恢复 ##

### 4.1 备份数据 ###

#### 4.1.1 插入数据 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 put test1 value1

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 put test2 value2

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 put test3 value3

![在这里插入图片描述][a7145e29ae0e4ec1af1dcd45c63d8146.png]

#### 4.1.2 开始备份数据 ####

./etcdctl --endpoints=http://192.168.159.200:2379 snapshot save /opt/bakup.db

![在这里插入图片描述][44bbb6e9a8d940238c476857235943f8.png]

#### 4.1.3 数据量查看 ####

./etcdctl --write-out=table --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 snapshot status /opt/bakup.db

![在这里插入图片描述][ad0024e3093a4ecaa878e75ba1c68b70.png]

### 4.2 数据恢复 ###

#### 4.2.1 删除数据 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 del test1

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 del test2

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http://192.168.159.202:2379 del test3

#### 4.2.2 查看数据是否删除 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get test1

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get test2

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get test3

![在这里插入图片描述][942acc6ed64f46d3af354b817ec0e1a4.png]

#### 4.2.3 数据导入 ####

将备份文件bakup.db拷贝到集群所有节点，并在每个节点执行如下命令。

linux1

./etcdctl snapshot restore /opt/bakup.db \
    --data-dir="/root/software/etcd-v3.5.4-linux-amd64/data2" \
    --name linux1 \
    --initial-cluster "linux1=http://192.168.159.200:2380,linux2=http://192.168.159.201:2380,linux3=http://192.168.159.202:2380" \
    --initial-cluster-token etcd-cluster-token \
    --initial-advertise-peer-urls "http://192.168.159.200:2380"

![在这里插入图片描述][a76e34a8d31840d3b67467aab1a05ea8.png]  
linux2

./etcdctl snapshot restore /opt/bakup.db \
    --data-dir="/root/software/etcd-v3.5.4-linux-amd64/data2" \
    --name linux2 \
    --initial-cluster "linux1=http://192.168.159.200:2380,linux2=http://192.168.159.201:2380,linux3=http://192.168.159.202:2380" \
    --initial-cluster-token etcd-cluster-token \
    --initial-advertise-peer-urls "http://192.168.159.201:2380"

![在这里插入图片描述][67312ff46f4148a09686cdeccce0821d.png]  
linux3

./etcdctl snapshot restore /opt/bakup.db \
    --data-dir="/root/software/etcd-v3.5.4-linux-amd64/data2" \
    --name linux3 \
    --initial-cluster "linux1=http://192.168.159.200:2380,linux2=http://192.168.159.201:2380,linux3=http://192.168.159.202:2380" \
    --initial-cluster-token etcd-cluster-token \
    --initial-advertise-peer-urls "http://192.168.159.202:2380"

![在这里插入图片描述][d2dc3d1ac4014a19a06900c463eedc19.png]

#### 4.2.4 停止集群所有节点的etcd服务 ####

#### 4.2.5 启动新的目录启etcd服务 ####

需修改配置文件etcd-conf.yml中的数据存储目录  
![在这里插入图片描述][72908796e27741fdbefafb242df97cf2.png]

#### 4.2.6 数据验证 ####

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get test1

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get test2

./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get test3

![在这里插入图片描述][807102cd46c4425ea96652993a34d4b1.png]

## 5 常见操作 ##

### 5.1 插入数据和获取数据 ###

# 插入数据
    etcdctl --endpoints=$ENDPOINTS put web1 value1
    etcdctl --endpoints=$ENDPOINTS put web2 value2
    etcdctl --endpoints=$ENDPOINTS put web3 value3
    
    # 根据前缀获取数据
    etcdctl --endpoints=$ENDPOINTS get web --prefix

例子：

# 插入数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put k1 v1
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put k2 v2
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put k3 v3
    
    # 获取单条数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get k1
    
    # 根据前缀获取数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get k --prefix

![在这里插入图片描述][675c0ef4c8504c529e9a4f7563e260a3.png]

### 5.2 删除数据 ###

etcdctl --endpoints=$ENDPOINTS put key myvalue
    etcdctl --endpoints=$ENDPOINTS del key
    
    etcdctl --endpoints=$ENDPOINTS put k1 value1
    etcdctl --endpoints=$ENDPOINTS put k2 value2
    etcdctl --endpoints=$ENDPOINTS del k --prefix

例子：

# 插入数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put key myvalue
    # 删除数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 del key
    # 获取数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get key
    
    # 插入2条数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put k1 value1
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put k2 value2
    # 根据前缀删除数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 del k --prefix
    # 获取数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get k1
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get k2

![在这里插入图片描述][e3e12884d1ee4db19a63d63daa34db03.png]

### 5.3 事务操作 ###

etcdctl --endpoints=$ENDPOINTS put user1 bad
    etcdctl --endpoints=$ENDPOINTS txn --interactive
    
    compares:
    value("user1") = "bad"
    
    success requests (get, put, delete):
    del user1
    
    failure requests (get, put, delete):
    put user1 good

例子：

# 插入数据
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put user1 bad
    # 开启事务
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 txn --interactive
    compares:
    value("user1") = "bad"
    
    success requests (get, put, del):
    del user1
    
    failure requests (get, put, del):
    put user1 good
    
    SUCCESS

![在这里插入图片描述][3e6cf95e6cf348a2b24377d0a6c6e1b9.png]

### 5.4 监控某个值 ###

etcdctl --endpoints=$ENDPOINTS watch stock1
    etcdctl --endpoints=$ENDPOINTS put stock1 1000
    
    etcdctl --endpoints=$ENDPOINTS watch stock --prefix
    etcdctl --endpoints=$ENDPOINTS put stock1 10
    etcdctl --endpoints=$ENDPOINTS put stock2 20

例子：

# 设置stock1的值，默认值为0
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put stock1 0
    # 监控key为stock1的值
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 watch stock1
    
    # 修改stock1的值
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put stock1 1000
    
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put stock1 1001

![在这里插入图片描述][c6545cdabc544e30ba6d8288fa88b198.png]

![在这里插入图片描述][289dc0d413b94fb2a7e9558940ba6b1b.png]  
前缀值监控：

# 前缀值监控
    # 设置chen1的值，默认值为0
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put chen1 0
    # 设置chen2的值，默认为1
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put chen2 1
    # 监控前缀为chen的值
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 watch chen --prefix
    
    # 修改chen1和chen2的值
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put chen1 10
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put chen2 20

![在这里插入图片描述][0b8aff3109d94ff1951becc09b4c75bd.png]  
![在这里插入图片描述][7c27cdc4c0b04d329587febd5b626ed5.png]

### 5.5创建租约 ###

grant		Creates leases
    keep-alive	Keeps leases alive (renew)
    list		List all active leases
    revoke		Revokes leases
    timetolive	Get lease information
    
    etcdctl --endpoints=$ENDPOINTS lease grant 300
    # lease 2be7547fbc6a5afa granted with TTL(300s)
    
    etcdctl --endpoints=$ENDPOINTS put sample value --lease=2be7547fbc6a5afa
    etcdctl --endpoints=$ENDPOINTS get sample
    
    etcdctl --endpoints=$ENDPOINTS lease keep-alive 2be7547fbc6a5afa
    etcdctl --endpoints=$ENDPOINTS lease revoke 2be7547fbc6a5afa
    # or after 300 seconds
    etcdctl --endpoints=$ENDPOINTS get sample

例子：

# 创建租约
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 lease grant 300
    # lease 5ece82ff7769d712 granted with TTL(300s)
    # 给某个值赋予租约
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 put sample value --lease=5ece82ff7769d712
    
    # 查看租约剩余时间
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 lease timetolive 5ece82ff7769d712
    # 租约时间到后无法查询其值

![在这里插入图片描述][02730df9fcff4de0aa30c0be0d23c182.png]  
在租约有效期时间内可以正常查看其值  
![在这里插入图片描述][957c77190605443b9b512cb837acee70.png]  
租约时间失效后，无法正常查看其值  
![在这里插入图片描述][047041f3d0eb473a81de62e0600a4a3f.png]  
如果在截止时间结束后再续约，则会报错，表示该租约以过期，不能继续续约  
![在这里插入图片描述][9c875be43b3c4e6ca51f768591365bf2.png]

# 创建租约
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 lease grant 100
    # lease 455182ff7785601a granted with TTL(300s)
    # 查看租约剩余时间
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 lease timetolive 455182ff7785601a
    
    # 续租约
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 lease keep-alive 455182ff7785601a
    
    # 查看租约剩余时间
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 lease timetolive 455182ff7785601a
    
    # 删除租约
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 lease revoke 455182ff7785601a
    # 获取值
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 get sample

![在这里插入图片描述][fb0bf29b8c534dd38c77b9fdff40a37a.png]

### 5.6 创建锁 ###

tcdctl --endpoints=$ENDPOINTS lock mutex1
    
    # another client with the same name blocks
    etcdctl --endpoints=$ENDPOINTS lock mutex1

例子：

# 创建一个锁
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 lock mutex1
    
    # 其他节点也去访问这个锁住的节点没有返回
    ./etcdctl --endpoints=http://192.168.159.200:2379,http://192.168.159.201:2379,http:192.168.159.202:2379 lock mutex1

![在这里插入图片描述][a975ea053ad74895af8439eaa399d156.png]  
![在这里插入图片描述][ef2114227b2a48f0ab2692e7808fc8fd.png]

我们将节点1关闭，发现节点2获取锁  
![在这里插入图片描述][dffbc2a210ee4e26937e886510f82190.png]  
![在这里插入图片描述][5bacbcb9ef8f43268a792194fd254d55.png]

[3f4829d41205452d89f068013a5d31d6.png_pic_center]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/2a10f0d5bae74118a7d857cd19fc3fc1.png
[173c917936fc48edb0fc385c884c7405.png_pic_center]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/6b43e700ff12412b92c061567eac3c22.png
[462de3646eea457383b474145aaa74af.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/e82872fad07a48038d0a7400824b0fb7.png
[195bc1be21634918b610ce187d2a7d92.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/31040160bcb74d1d866520c0d5562ac3.png
[534bb13cc17b48e4a8fc3bb9d1b100e5.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/af05fd0d24be426fb614e285a7e98f6c.png
[39197ad618314d219ebfef06038a65e2.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/39ad1008a8c0497e85e9d0282af37228.png
[7380d9357ca54352b55dbea9d4acae63.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/ebe889ffb7ba4a04ac5b94d8ec6aeaf0.png
[9987651976f04209b5ab91982f02a6c0.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/5a68e7c64b6041879ac9ae9bdec21c10.png
[7c2219f0114b4796b0ba328812a3b3f1.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/52b5bb8a9ae64e3ba52bee76041d5f76.png
[4f4460f4c12743dfaa99ddb180f71ba8.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/91388c74dbd240faa3cd7170b2d90d22.png
[edc1bd0bb2db4581921f76df65d99583.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/54df77979be44d0e9f50a1ab0857b8ee.png
[27a307c502e146ceb0048b5bc32fbdc7.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/59971382397a42b598678b2196b36a24.png
[a2a3823c36c74a28abee91e598867327.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/762b94d60e7245f5a617996172edbb13.png
[01d70df990154373bfcf746bad5b8182.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/d96e5a32cb2f47dca4f85f7e01ca05be.png
[c7c60d6167074fae88d85b4b5b8306a5.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/b49bf0474bc64795855e3a5a8390d4d7.png
[3a1c7849d3534fb1b1c0209a27d51a37.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/3fb09d6bfeae44eabe23922562e91edc.png
[a763381211c547ba8e655acf48556e42.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/5ae8d99609084127bdc64cae90cab67b.png
[a7145e29ae0e4ec1af1dcd45c63d8146.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/9904a5ee4a7b44e29aaa79220bb7b45a.png
[44bbb6e9a8d940238c476857235943f8.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/4e6e825b7aa64953a12d0020e4999b09.png
[ad0024e3093a4ecaa878e75ba1c68b70.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/9b885f35d5a245328c3524f4f1fc0d1e.png
[942acc6ed64f46d3af354b817ec0e1a4.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/50b9cc3d592247f797f3958527834fc1.png
[a76e34a8d31840d3b67467aab1a05ea8.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/2a02612e931a4e668ec3ea8d47a7f051.png
[67312ff46f4148a09686cdeccce0821d.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/9b3baa3113cc4daba3563f2115ebb1f5.png
[d2dc3d1ac4014a19a06900c463eedc19.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/f50eb4e209fa4a9391d7f288051d5881.png
[72908796e27741fdbefafb242df97cf2.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/644683e6e91d45e08916f3eaeb8d816d.png
[807102cd46c4425ea96652993a34d4b1.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/3938a053b83347639f778917a1984957.png
[675c0ef4c8504c529e9a4f7563e260a3.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/b940503aec584de4a874f6fb2a303394.png
[e3e12884d1ee4db19a63d63daa34db03.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/db56c421d40e406195dc09ddde3897fa.png
[3e6cf95e6cf348a2b24377d0a6c6e1b9.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/937764fc5f694aa0a6e17056e5855fbf.png
[c6545cdabc544e30ba6d8288fa88b198.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/9c9c1bf2b8e74f4fb2bf60ea0b288668.png
[289dc0d413b94fb2a7e9558940ba6b1b.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/9a6f7a22de4741ffa82bb47a9d878a22.png
[0b8aff3109d94ff1951becc09b4c75bd.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/e12c169ed10a44fd915ef807271192b1.png
[7c27cdc4c0b04d329587febd5b626ed5.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/65a688dfcad4495fb0d3917e47c56f7c.png
[02730df9fcff4de0aa30c0be0d23c182.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/fd1aa562abee4746b7a2c84b0e644bb9.png
[957c77190605443b9b512cb837acee70.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/64e855878889431497f264ba63a185c2.png
[047041f3d0eb473a81de62e0600a4a3f.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/d23c8e3e852e41aba67e809e0b9a7702.png
[9c875be43b3c4e6ca51f768591365bf2.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/5a9a0f9f04334689ba6f7874d35e41bb.png
[fb0bf29b8c534dd38c77b9fdff40a37a.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/723a8c519754434fb7988930caa43b27.png
[a975ea053ad74895af8439eaa399d156.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/a15d1847b06e47548a55cb2c0b7261a9.png
[ef2114227b2a48f0ab2692e7808fc8fd.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/713c97de84b24001b62f4d9ced495259.png
[dffbc2a210ee4e26937e886510f82190.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/7bd833c7e9d34ac1935d3e9e1f6ab5e8.png
[5bacbcb9ef8f43268a792194fd254d55.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/07/03f867d0feec46dbb24d706bde1e3a1b.png