分发系统-expect讲解

• 业务越来越大，网站app，后端，编程语言是php，所以就需要配置lamp或者lnmp，最好还需要吧代码上传到服务器上；但是因为业务增加，代码增加，多台机器，就会非常麻烦；这是只需要一个分发系统，就可以把每次更新的代码发布到需要更新的服务器上
• expect，是一种脚本语言；通过他可以实现传代码上线，也可以登录机器输入命令
• 首先要准备一台模板机器，机器的IP，对应用户的密码，通过rsync同步代码，还可以通过expect去执行某些命令
  

  expect脚本远程登录

• yum install -y expect
• 自动远程登录

  [[email protected] sbin]# vim 1.expect
  [[email protected] sbin]# vim 1.expect
  #! /usr/bin/expect
  set host "192.168.21.129"
  set passwd "s5381561"
  spawn ssh [email protected]$host
  expect {
  "yes/no" { send "yes\r"; exp_continue}
  "password:" { send "$passwd\r" }
  }
  interact
  [[email protected] sbin]# chmod a+x 1.expect
  [email protected] sbin]# ./1.expect
  spawn ssh [email protected]
  The authenticity of host ‘192.168.21.129 (192.168.21.129)‘ can‘t be established.
  ECDSA key fingerprint is SHA256:r2y+hZVvvomXE4d3uRSM0cO+kMdqyWAOMqpTtA2qp6I.
  ECDSA key fingerprint is MD5:ee:da:3b:ea:27:56:38:82:bc:e8:73:10:18:a0:c2:bd.
  Are you sure you want to continue connecting (yes/no)? yes
  Warning: Permanently added ‘192.168.21.129‘ (ECDSA) to the list of known hosts.
  [email protected]‘s password:
  Last login: Wed Jul 11 21:59:23 2018 from 192.168.21.1
  [[email protected] ~]# 

• 在expect 定义变量，用set
• 这个文件是就保证登录信息的，清空的话，重新远程登录ssh 会有提示 /root/.ssh/known_hosts
  exp_continue 表示继续 \r 表示换行 interact 继续停留在这台机器，不退出
  

  expect脚本远程执行命令

• 远程登录后，执行命令并退出

  [[email protected] sbin]# vim 2.expect
  #!/usr/bin/expect
  set user "root"
  set passwd "s5381561"
  spawn ssh [email protected]
  expect {
  "yes/no" { send "yes\r"; exp_continue}
  "password:" { send "$passwd\r" }
  }
  expect "]*"
  send "touch /tmp/12.txt\r"
  expect "]*"
  send "echo 1212 > /tmp/12.txt\r"
  expect "]*"
  send "exit\r"
  [[email protected] sbin]# chmod a+x 2.expect
  [[email protected] sbin]# ./2.expect
  spawn ssh [email protected]
  [email protected]‘s password:
  Last login: Sun Jul 22 22:07:20 2018 from 192.168.21.128
  [[email protected] ~]# touch /tmp/12.txt
  [[email protected] ~]# echo 1212 > /tmp/12.txt
  [[email protected] ~]# [[email protected] sbin]#
  [[email protected] ~]# ls /tmp/
  12.txt
  mysql.sock
  systemd-private-12cfefcc2aaa4137b4ea969d11fbf699-chronyd.service-5DHBEF
  systemd-private-12cfefcc2aaa4137b4ea969d11fbf699-vgauthd.service-sG39NN
  systemd-private-12cfefcc2aaa4137b4ea969d11fbf699-vmtoolsd.service-CVypi4
  [[email protected] ~]# cat /tmp/12.txt
  1212

• expect "]*" ： “” 通配]右边所有字符
• send 执行命令
  

  expect脚本传递参数

• 传递参数

  [[email protected] sbin]# vim 3.expect
  #!/usr/bin/expect
  set user [lindex $argv 0]  #第一个参数赋值给user
  set host [lindex $argv 1]  #第二个参数
  set passwd "s5381561"
  set cm [lindex $argv 2]    #第三个参数
  spawn ssh [email protected]$host
  expect {
  "yes/no" { send "yes\r"}
  "password:" { send "$passwd\r" }
  }
  expect "]*"
  send "$cm\r"
  expect "]*"
  send "exit\r"
  [[email protected] sbin]# chmod a+x 3.expect
  [[email protected] sbin]# ./3.expect root 192.168.21.129 ls
  spawn ssh [email protected]
  [email protected]‘s password:
  Last login: Sun Jul 22 22:14:12 2018 from 192.168.21.1
  [[email protected] ~]# ls
  111  anaconda-ks.cfg
  [[email protected] ~]# [[email protected] sbin]#
  [[email protected] ~]# [[email protected] sbin]# ./3.expect root 192.168.21.129 "ls;w;vmstat 1"
  spawn ssh [email protected]
  [email protected]‘s password:
  Last login: Sun Jul 22 22:19:35 2018 from 192.168.21.128
  [[email protected] ~]# ls;w;vmstat 1
  111  anaconda-ks.cfg
  22:19:51 up 41 min,  2 users,  load average: 0.00, 0.02, 0.05
  USER     TTY      FROM             [email protected]   IDLE   JCPU   PCPU WHAT
  root     pts/0    192.168.21.1     22:14   55.00s  0.01s  0.01s -bash
  root     pts/1    192.168.21.128   22:19    0.00s  0.01s  0.00s w
  procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
  r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
  2  0      0 1142532   2076 173112    0    0    15    14   51   44  0  0 99  0  0
  0  0      0 1142780   2076 173208    0    0     0     6  257  149  0  0 100  0  0
  0  0      0 1142780   2076 173208    0    0     0   294  188  181  0  0 100  0  0
  0  0      0 1142780   2076 173208    0    0     0     0  122  112  0  0 100  0  0
  0  0      0 1142780   2076 173208    0    0     0     0  116  105  0  0 100  0  0
  0  0      0 1142780   2076 173208    0    0     0     0  107   99  0  0 100  0  0
  0  0      0 1142780   2076 173208    0    0     0     0  160  136  0  0 100  0  0
  0  0      0 1142780   2076 173208    0    0     0     5  124  119  0  0 100  0  0
  0  0      0 1142780   2076 173208    0    0     0   168  157  157  0  0 100  0  0
  0  0      0 1142780   2076 173208    0    0     0     0  102   99  0  0 100  0  0
  0  0      0 1142780   2076 173208    0    0     0     0  119  113  0  0 100  0  0
  [[email protected] sbin]# 

• 支持多条参数运行，vmstat 1命令10秒后自动退出

原文地址：http://blog.51cto.com/akui2521/2148777