expect交互工具

红太狼 2022-05-18 06:55 279阅读 0赞

*  1.expect简介
 *  2.expect安装(默认未安装)
 *  3.命令与参数解释
    
     *  3.1脚本开头
     *  3.2常用后缀
     *  3.3主要命令
 *  4.实例操作：
    
     *  4.1通过expect脚本，实现ssh自动化连接
        
         *  4.1.1expect脚本内容与解释
         *  4.1.2执行expect脚本
     *  4.2通过expect脚本，实现免秘钥
        
         *  4.2.1实验环境（主机名与IP）
         *  4.2.2在服务端生成秘钥
         *  4.2.3编写shell嵌套expect脚本进行免秘钥操作
         *  4.2.4执行脚本
         *  4.2.5验证
     *  4.3通过执行 脚本+用户@IP+密码，实现免秘钥。（例如：bash ssh\_user.sh root@10.0.0.130 000000）
        
         *  4.3.1脚本内容与解释
         *  4.3.2删除主机的秘钥（前面把公钥发过去了，先删掉）
         *  4.3.3执行脚本
         *  4.3.4测试

# 1.expect简介 #

*  expect是一个用来处理交互的命令。 借助expect，我们可以将交互过程写在一个脚本上，使之自动化完成。

# 2.expect安装(默认未安装) #

[root@liang ~]# yum install expect -y

# 3.命令与参数解释 #

## 3.1脚本开头 ##

*  expect脚本一般以\#!/usr/bin/expect -f 开头，类似bash脚本。

## 3.2常用后缀 ##

*  expect脚本常常以.exp或者.ex结束。

## 3.3主要命令 ##

<table> 
 <thead> 
  <tr> 
   <th>命令</th> 
   <th align="right">解释</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>send</td> 
   <td align="right">用于向进程发送字符串</td> 
  </tr> 
  <tr> 
   <td>expect</td> 
   <td align="right">从进程接收字符串</td> 
  </tr> 
  <tr> 
   <td>spawn</td> 
   <td align="right">启动新的进程</td> 
  </tr> 
  <tr> 
   <td>interact</td> 
   <td align="right">允许用户交互</td> 
  </tr> 
  <tr> 
   <td>exp_continue</td> 
   <td align="right">匹配多个字符串在执行动作后加此命令</td> 
  </tr> 
  <tr> 
   <td>set</td> 
   <td align="right">设定变量值</td> 
  </tr> 
  <tr> 
   <td>[lindex $argv 0]</td> 
   <td align="right">获取expect脚本的第1个参数,</td> 
  </tr> 
  <tr> 
   <td>set timeout 5</td> 
   <td align="right">设置超时时间，单位为秒，-1为没有限制</td> 
  </tr> 
  <tr> 
   <td>expect eof</td> 
   <td align="right">等待spawn进程结束后退出信号eof</td> 
  </tr> 
 </tbody> 
</table>

# 4.实例操作： #

## 4.1通过expect脚本，实现ssh自动化连接 ##

### 4.1.1expect脚本内容与解释 ###

[root@liang 2018-07-30]# cat expect.exp 
    #!/usr/bin/expect -f
    set timeout -1 #永远不会超时
    set ip 10.0.0.130 #定义变量ip=10.0.0.130
    set password 000000
    spawn ssh root@${ip}#启动 ssh连接 root@10.0.0.130 的进程
    expect {
       #接受进程的字符串
            "yes/no" {send "yes\r";exp_continue}#如果字符串包含"yes/no"，则发送“yes”并回车，继续匹配
            "password" {send "${password}\r"};
    }
    interact #ssh连接后，停留在被控制端

### 4.1.2执行expect脚本 ###

[root@liang 2018-07-30]# expect expect.exp 
    spawn ssh root@10.0.0.130
    root@10.0.0.130's password: 
    Last login: Tue Jul 31 01:08:32 2018 from 10.0.0.129
    [root@haproxy ~]# date
    Tue Jul 31 01:09:33 EDT 2018

## 4.2通过expect脚本，实现免秘钥 ##

### 4.2.1实验环境（主机名与IP） ###

liang 10.0.0.129（秘钥服务端）
    haproxy 10.0.0.130
    nginx 10.0.0.131
    mysql 10.0.0.132

### 4.2.2在服务端生成秘钥 ###

[root@liang ~]# ssh-keygen（打完这条命令，一直按回车） 
    Generating public/private rsa key pair.
    Enter file in which to save the key (/root/.ssh/id_rsa): 
    Enter passphrase (empty for no passphrase): 
    Enter same passphrase again: 
    Your identification has been saved in /root/.ssh/id_rsa.
    Your public key has been saved in /root/.ssh/id_rsa.pub.
    The key fingerprint is:
    ca:3d:85:7f:21:88:56:31:51:6c:1d:65:87:86:d4:e8 root@rsync-A
    The key's randomart image is:
    +--[ RSA 2048]----+
    |        ++.oo*o..|
    |         oo +.+. |
    |        .. . .   |
    |       o o  E    |
    |      o S o .    |
    |     o o o . .   |
    |      o o . .    |
    |         . .     |
    |                 |
    +-----------------+

### 4.2.3编写shell嵌套expect脚本进行免秘钥操作 ###

[root@liang 2018-07-30]# cat ssh.sh 
    #!/bin/bash #shell脚本解释器
    password=000000#设置变量，我这里所有虚拟机的密码都为000000
    for ip in `seq 130 132` #循环主机
    do
        expect -c " #调用expect命令
            spawn ssh-copy-id -i /root/.ssh/id_rsa.pub 10.0.0.$ip #发送公钥的虚拟机
            expect {
                    \"yes/no\" { send \"yes\r\";exp_continue }#这里的写法跟前面一样，\"\"(只是所有双引号的前面都需要加个\转义符号)
                    \"password\" { send \"${password}\r\"}
            };#结尾需要加分号
            expect eof #结束进程
        "
    done

### 4.2.4执行脚本 ###

[root@liang 2018-07-30]# bash ssh.sh 
    spawn ssh-copy-id -i /root/.ssh/id_rsa.pub 10.0.0.130
    root@10.0.0.130's password: 
    Now try logging into the machine, with "ssh '10.0.0.130'", and check in:
    
      .ssh/authorized_keys
    
    to make sure we haven't added extra keys that you weren't expecting.
    
    spawn ssh-copy-id -i /root/.ssh/id_rsa.pub 10.0.0.131
    root@10.0.0.131's password: 
    Now try logging into the machine, with "ssh '10.0.0.131'", and check in:
    
      .ssh/authorized_keys
    
    to make sure we haven't added extra keys that you weren't expecting.
    
    spawn ssh-copy-id -i /root/.ssh/id_rsa.pub 10.0.0.132
    root@10.0.0.132's password: 
    Now try logging into the machine, with "ssh '10.0.0.132'", and check in:
    
      .ssh/authorized_keys
    
    to make sure we haven't added extra keys that you weren't expecting.

### 4.2.5验证 ###

[root@liang 2018-07-30]# ssh 10.0.0.130
    Last login: Tue Jul 31 01:08:52 2018 from 10.0.0.129
    [root@haproxy ~]# exit
    logout
    Connection to 10.0.0.130 closed.
    [root@liang 2018-07-30]# ssh 10.0.0.131
    Last login: Tue Jul 31 01:24:56 2018 from 10.0.0.129
    [root@nginx ~]# exit
    logout
    Connection to 10.0.0.131 closed.
    [root@liang 2018-07-30]# ssh 10.0.0.132
    Last login: Mon Jul 30 11:15:28 2018 from 10.0.0.1
    [root@mysql ~]# exit
    logout
    Connection to 10.0.0.132 closed.

## 4.3通过执行 脚本+用户@IP+密码，实现免秘钥。（例如：bash ssh\_user.sh root@10.0.0.130 000000） ##

### 4.3.1脚本内容与解释 ###

[root@liang 2018-07-30]# cat ssh_user.exp 
    #!/usr/bin/expect -f #expect的解释器
    set user_ip [lindex $argv 0] #设置user_ip变量=用户输入的第一个变量
    set password [lindex $argv 1] #设置password变量=用户输入的第二个变量
    spawn ssh-copy-id -i /root/.ssh/id_rsa.pub ${user_ip} #发送公钥给用户输入的用户
    expect {
            "yes/no" { send "yes\r";exp_continue }
             "password" { send "${password}\r"};
    }
    expect eof

### 4.3.2删除主机的秘钥（前面把公钥发过去了，先删掉） ###

[root@liang 2018-07-30]# ssh root@10.0.0.130 rm -rf /root/.ssh/authorized_keys
    [root@liang 2018-07-30]# ssh root@10.0.0.130
    root@10.0.0.130's password:

### 4.3.3执行脚本 ###

[root@liang 2018-07-30]# expect ssh_user.exp root@10.0.0.130 000000
    spawn ssh-copy-id -i /root/.ssh/id_rsa.pub root@10.0.0.130
    root@10.0.0.130's password: 
    Now try logging into the machine, with "ssh 'root@10.0.0.130'", and check in:
    
      .ssh/authorized_keys
    
    to make sure we haven't added extra keys that you weren't expecting.

### 4.3.4测试 ###

[root@liang 2018-07-30]# ssh 10.0.0.130
    Last login: Tue Jul 31 01:29:52 2018 from 10.0.0.129
    [root@haproxy ~]# exit
    logout
    Connection to 10.0.0.130 closed.