多系统管理 expect,python,screen

    作为系统管理员经常碰到的问题就是 给这 30 台机器装个软件，给哪50台机器装个软件的。我使用的系统是 linux 现在管理的服务器大概有几百台了。都是用户名和密码，没加 key 认证，网上一般都说加 ssh-key 然后 怎么怎么实现之类的。这里放出我的方法。

方法1：用 expect 脚本实现。 （需要安装 expect 包）

#!/usr/bin/expect -f
exp_version -exit 5.0
set Conf "./exp_auto_run.conf"
set Default_User defusername
set Default_PWD defpassword
set timeout 60
if {$argc!=0} {
    send_user "usage: $argv0 host1 host2 host3 . . .\n";
    send_user "usage: $argv0 $argc [lrange $argv 0 $argc]\n";
    send_user "argv 0 is [lindex $argv 0]\n"
}
if {![file exists $Conf]} {
    puts "no fonnd $Conf"
    exit 1
}
set fileId [open $Conf r 0400]
set contents [read $fileId]
close $fileId
foreach i [split $contents \n] {
    if {[string match host=* $i]} {
        foreach j $i {
            switch -regexp -- $j {
                ^host=.+ {set host [lindex [split $j =] 1]}
                ^port=.+ {set port [lindex [split $j =] 1]}
                ^username=.+ {set username [lindex [split $j =] 1]}
                ^password=.+ {set password [lindex [split $j =] 1]}
            }
            if {![info exists port]} {
                set port [lindex [split $host .] 3]22
            }
            if {![info exists username]} {
                set username $Default_User
            }
            if {![info exists password]} {
                set password $Default_PWD
            }
        }
        spawn ssh -l $username $host -p $port
        expect {
            "(yes/no)" {send "yes\r";exp_continue}
            "assword:" {send "${password}\r";exp_continue}
            -re ".\+]\\\$" {send "sudo -s\r";exp_continue}
            -re ".\+]\\\#" {send "su -l\r";}
        }
        foreach cmd {
                "echo running command at server"
        } {
            expect -re ".\+]#" {send "${cmd}\r"}
        }
        sleep .1
        expect -re "\\\[.\+]" {send ":\r"}
        close -i $spawn_id
        unset host port username password
    }
}

exit

配置文件是：

# Expect Config File
# [HOST]        [PORT]        [USERNAME]        [PASSWORD]
host=192.168.1.2    port=22    username=u_admin        password=p_admin

方法2：
用 python 的 pexpect 实现，需要装 pexpect 模块

#!/usr/bin/python

"""connect ssh pexpect"""

import os,sys,pexpect

def connect_host(host_dic):
    connect_host = pexpect.spawn('ssh -l %s %s -p %s' % (host_dic["username"],host_dic["host"],host_dic["port"]))
    while(1):
        index = connect_host.expect(['.assword:','.*(yes/no).','.*[#\$] ',pexpect.EOF,pexpect.TIMEOUT])
        if index == 0:
            connect_host.sendline(host_dic["password"])
        elif index == 1:
            connect_host.sendline("yes")
        elif index == 2:
            connect_host.sendline("")
            break
        elif index == 3:
            break
        elif index == 4:
            break
        else:
            sys.exit(1)
    connect_host.interact()
    connect_host.close()

def main():
    host_list={"host":"192.16.1.3","username":"u_admin","password":"p_admin","port":"22"}
    connect_host(host_list)
    sys.exit(0)

main()

方法3： 用 ssh + screen 实现。

function conn_server() {    local _U="username" _P    >/${USER}/.ssh/known_hosts    for ip in 2 3 4 5 6 7 8 9;do        screen -S ${STY} -X screen -t web ssh -l ${_U} 192.168.1.${ip} -p 22    done    screen -S ${STY} -X select 0    stty -echo    read -t 60 -p "Password: " _P    stty echo    sleep 2    screen -S ${STY} -X at web# stuff $'yes\x0a'    sleep 2    screen -S ${STY} -X at web# stuff "${_P:-defpassword}"$'\x0a'
    unset _P    sleep .5    screen -S ${STY} -X at web# stuff $'sudo -s\x0a'    sleep .5    screen -S ${STY} -X at web# stuff $'su -l\x0a'
}
function all_run() { screen -S ${STY} -X at web# stuff "$@"$'\x0a'; }

screen -S admin
conn_server
all_run "echo running at remove server"

多个脚本用途各有各的不同，妙用在那里需要自己体会使用了 .