ssh自动登录的4种实现方法

ssh自动登录的几种实现方法，记录在此。 

1. 自动ssh/scp方法

A为本地主机(即用于控制其他主机的机器) ;

B为远程主机(即被控制的机器Server), 假如ip为192.168.60.110;

A和B的系统都是Linux

在A上运行命令:

# ssh-keygen -t rsa (连续三次回车,即在本地生成了公钥和私钥,不设置密码)

# ssh root@192.168.60.110 "mkdir .ssh" (需要输入密码)

# scp ~/.ssh/id_rsa.pub root@192.168.60.110:.ssh/id_rsa.pub (需要输入密码)

在B上的命令:

# touch /root/.ssh/authorized_keys (如果已经存在这个文件, 跳过这条)

# cat /root/.ssh/id_rsa.pub >> /root/.ssh/authorized_keys (将id_rsa.pub的内容追加到authorized_keys 中)

回到A机器:

# ssh root@192.168.60.110 (不需要密码, 登录成功)

2. 控制n个机器如上所述自动登录

那就需要n对钥匙(密钥和公钥), ssh-keygen 命令可以随意更改钥匙对的名字, 比如:

# ssh-keygen -t rsa

Generating public/private rsa key pair.

Enter file in which to save the key (/root/.ssh/id_rsa): /root/.ssh/id_rsa_192.168.60.110

这样私钥和公钥的名字分别就是: id_rsa_192.168.60.110和 id_rsa_192.168.60.110.pub;然后将 id_rsa_192.168.60.110.pub 文件的内容, 追加到sever的 ~/.ssh/authorized_keys文件中,最后, 在本地用ssh命令的 -i 参数指定本地密钥, 并登录:

# ssh -i /root/.ssh/id_rsa_192.168.60.110 someone@192.168.60.110

scp也是一样的

# scp -i /root/.ssh/id_rsa_192.168.60.110 filename someone@192.168.60.110:/home/someone

在文件.bashrc中加下两行，每次做同样的操作就不用敲入这样长的命令了：

alias sshcell='ssh -i /root/.ssh/id_rsa_192.168.60.110 someone@192.168.60.110'

alias scpcell='scp -i /root/.ssh/id_rsa_192.168.60.110 filename someone@192.168.60.110:/home/someone'

这样，直接键入一下指令实现ssh和scp自动登录：

# sshcell

# scpcell

3. 自动ssh/scp脚本

如果需要从A，到B，然后才能够到C，那么需要ssh和scp两次，是比较麻烦的。

ssh自动登录：

#!/usr/bin/expect -f

set timeout 30

spawn ssh weiqiong@B

expect "password:"

send "ppppppr"

expect "]*"

send "ssh weiqiong@Cr"

expect "password:"

send "ppppppr"

interact

scp从A拷贝文件到C：

#!/usr/bin/expect -f

set timeout 300

set file [lindex $argv 0]

spawn scp $file weiqiong@B:/home/weiqiong

expect "password:"

send "ppppppr"

expect "]*"

spawn ssh weiqiong@B

expect "password:"

send "ppppppr"

expect "]*"

send "scp $file weiqiong@C:/home/weiqiongr"

expect "password:"

send "ppppppr"

expect "]*"

exit

interact

scp从C拷贝文件到A：

#!/usr/bin/expect -f

set timeout 300

set file [lindex $argv 0]

spawn ssh weiqiong@B

expect "password:"

send "ppppppr"

expect "]*"

send "scp weiqiong@C:/home/weiqiong/$file .r"

expect "password:"

send "ppppppr"

expect "]*"

send "exitr"

expect "]*"

spawn scp weiqiong@B:/home/weiqiong/$file .

expect "password:"

send "ppppppr"

interact

4. 建立ssh/scp通道

比如说我的机器是A，中间服务器为B，目标服务器是C

从A可以ssh到B，从B可以ssh到C，但是A不能直接ssh到C

现在展示利用ssh通道技术从A直接传输文件到C

1. ssh -L1234:C:22 userid@B

input B's password

(1234是本机A的空闲端口，该指令需要A机器上的root用户权限，实际上是在本机1234端口建立了一个通道)

2. 打开一个新的console，键入：

scp -P1234 filename userid@localhost:

input C's password