简介： 此脚本需要用到expect和openssh的知识点。
关于openssh可见往期文章 点此前往
1. expect
| 参数 | 解释 |
|---|---|
| expect | 自动应答命令（用于交互式命令的自动执行） |
| set timeout 1 | 等待1秒再向下执行/-1为永不超时 |
| set NAME [ lindex $argv 0 ] | 定义变量 |
| sapwn | 监控程序 |
| send | 发送问题答案给交互命令 |
| \r | 在终端敲回车 |
| exp_continue | 继续回答下面的 |
| expect eof | 表示回答完那些问题后，退出expect环境 |
| interact | 问题回答完后留在交互界面 |
//下载expect
[root@localhost ~]# yum -y install expect
[root@localhost ~]# expect -div
expect version 5.45
expect version 5.45
[root@localhost ~]# yum -y install expect
[root@localhost ~]# which expect
/usr/bin/expect
2. 脚本编辑
写脚本首先要手动执行一遍了解过程
//这是第一种情况
[root@localhost ~]# ssh-keygen
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:
SHA256:lqC2uv6o3F6X2umq2bzf57MpC40Rj0HB49gSfTH3uf0 root@localhost.localdomain
The key's randomart image is:
+---[RSA 2048]----+
| oo.o.. |
| ..+ .o . . |
| *oo o |
| + +=. o |
| o .oS. . . |
| . . .= .|
| .. = . E|
|. .o= + +. o. |
|.+*Bo*== o=+o |
+----[SHA256]-----+
总结一下就是ssh-keygen后按3下回车
//第二种情况，已经配置过免密，那么就要更新密码
[root@localhost ~]# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
/root/.ssh/id_rsa already exists.
Overwrite (y/n)? y
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:
SHA256:jnrscl5RGkiz9qL6bKtKV/mxbVY/CVs8m/LsBEYexEE root@localhost.localdomain
The key's randomart image is:
[root@localhost ~]# vim ssh.sh
[root@localhost ~]# cat ssh.sh
#!/bin/bash
read -p "Which IP address you want to connect to?:" ip
read -s -p "and password:" pwd #-s要在前面表示静默输出，保护密码
yum -y install openssh expect
expect << EOF #表示里面的内容均由expect命令去执行
set timeout 30 #设置超时时间为30秒，下面的代码需在30秒钟内完成，如果超过，则退出。用来防止ssh远程主机网络不可达时卡住及在远程主机执行命令宕住
spawn ssh-keygen #激活一个交互式会话，在系统中创建一个进程
expect {
".ssh/id_rsa)" {
send "\r"; exp_continue } #捕捉关键字，然后回车
"Overwrite (y/n)?" {
send "y\r"; exp_continue } #捕捉关键字后输入y然后回车
"no passphrase):" {
send "\r"; exp_continue }
"again:" {
send "\r"; exp_continue }
}
spawn ssh-copy-id root@$ip
expect {
"yes/no" {
send "yes\r"; exp_continue }
"password" {
send "$pwd\r"; exp_continue }
}
EOF
[root@localhost ~]# ./ssh.sh
Which IP address you want to connect to?:192.168.216.200
and password:1
spawn ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
/root/.ssh/id_rsa already exists.
Overwrite (y/n)? y
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:
SHA256:xaplvcpVheYg5sR/JU6QBlg+jMy9hYqxR1k7AiqK9Bk root@localhost.localdomain
The key's randomart image is:
+---[RSA 2048]----+
| . o+... |
| . +.O +o. . |
|...E. B &.= = o |
|+.. o= * @ * + |
|o oo o S o = |
| . + + |
| . o |
| . o |
| o |
+----[SHA256]-----+
spawn ssh-copy-id root@192.168.216.200
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@192.168.216.200's password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh '[email protected]'"
and check to make sure that only the key(s) you wanted were added.
2.1 测试
//恢复快照再次尝试
[root@localhost ~]# ./ssh.sh
Which IP address you want to connect to?:192.168.216.200^H^H^H^H^C
[root@localhost ~]# ./ssh.sh
Which IP address you want to connect to?:192.136^H^H^C
[root@localhost ~]# ./ssh.sh
Which IP address you want to connect to?:192.168.216.179
and password:1
Failed to set locale, defaulting to C.UTF-8
CentOS Linux 8 - AppStream 441 kB/s | 9.3 MB 00:21
CentOS Linux 8 - BaseOS 892 kB/s | 7.5 MB 00:08
CentOS Linux 8 - Extras 14 kB/s | 10 kB 00:00
Package openssh-8.0p1-5.el8.x86_64 is already installed.
Dependencies resolved.
=============================================================================================================================================================
Package Architecture Version Repository Size
=============================================================================================================================================================
Installing:
expect x86_64 5.45.4-5.el8 baseos 267 k
Upgrading:
openssh x86_64 8.0p1-6.el8_4.2 baseos 521 k
openssh-clients x86_64 8.0p1-6.el8_4.2 baseos 667 k
openssh-server x86_64 8.0p1-6.el8_4.2 baseos 484 k
Installing dependencies:
tcl x86_64 1:8.6.8-2.el8 baseos 1.1 M
Transaction Summary
=============================================================================================================================================================
Install 2 Packages
Upgrade 3 Packages
Total download size: 3.0 M
Downloading Packages:
(1/5): expect-5.45.4-5.el8.x86_64.rpm 680 kB/s | 267 kB 00:00
(2/5): openssh-8.0p1-6.el8_4.2.x86_64.rpm 862 kB/s | 521 kB 00:00
(3/5): openssh-server-8.0p1-6.el8_4.2.x86_64.rpm 726 kB/s | 484 kB 00:00
(4/5): openssh-clients-8.0p1-6.el8_4.2.x86_64.rpm 725 kB/s | 667 kB 00:00
(5/5): tcl-8.6.8-2.el8.x86_64.rpm 852 kB/s | 1.1 MB 00:01
-------------------------------------------------------------------------------------------------------------------------------------------------------------
Total 1.6 MB/s | 3.0 MB 00:01
warning: /var/cache/dnf/baseos-929b586ef1f72f69/packages/expect-5.45.4-5.el8.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID 8483c65d: NOKEY
CentOS Linux 8 - BaseOS 153 kB/s | 1.6 kB 00:00
Importing GPG key 0x8483C65D:
Userid : "CentOS (CentOS Official Signing Key) <[email protected]>"
Fingerprint: 99DB 70FA E1D7 CE22 7FB6 4882 05B5 55B3 8483 C65D
From : /etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
Key imported successfully
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
Preparing : 1/1
Running scriptlet: openssh-8.0p1-6.el8_4.2.x86_64 1/1
Running scriptlet: openssh-8.0p1-6.el8_4.2.x86_64 1/8
Upgrading : openssh-8.0p1-6.el8_4.2.x86_64 1/8
Installing : tcl-1:8.6.8-2.el8.x86_64 2/8
Running scriptlet: tcl-1:8.6.8-2.el8.x86_64 2/8
Installing : expect-5.45.4-5.el8.x86_64 3/8
Upgrading : openssh-clients-8.0p1-6.el8_4.2.x86_64 4/8
Running scriptlet: openssh-server-8.0p1-6.el8_4.2.x86_64 5/8
Upgrading : openssh-server-8.0p1-6.el8_4.2.x86_64 5/8
Running scriptlet: openssh-server-8.0p1-6.el8_4.2.x86_64 5/8
Running scriptlet: openssh-server-8.0p1-5.el8.x86_64 6/8
Cleanup : openssh-server-8.0p1-5.el8.x86_64 6/8
Running scriptlet: openssh-server-8.0p1-5.el8.x86_64 6/8
Cleanup : openssh-clients-8.0p1-5.el8.x86_64 7/8
Cleanup : openssh-8.0p1-5.el8.x86_64 8/8
Running scriptlet: openssh-8.0p1-5.el8.x86_64 8/8
Verifying : expect-5.45.4-5.el8.x86_64 1/8
Verifying : tcl-1:8.6.8-2.el8.x86_64 2/8
Verifying : openssh-8.0p1-6.el8_4.2.x86_64 3/8
Verifying : openssh-8.0p1-5.el8.x86_64 4/8
Verifying : openssh-clients-8.0p1-6.el8_4.2.x86_64 5/8
Verifying : openssh-clients-8.0p1-5.el8.x86_64 6/8
Verifying : openssh-server-8.0p1-6.el8_4.2.x86_64 7/8
Verifying : openssh-server-8.0p1-5.el8.x86_64 8/8
Upgraded:
openssh-8.0p1-6.el8_4.2.x86_64 openssh-clients-8.0p1-6.el8_4.2.x86_64 openssh-server-8.0p1-6.el8_4.2.x86_64
Installed:
expect-5.45.4-5.el8.x86_64 tcl-1:8.6.8-2.el8.x86_64
Complete!
spawn ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Created directory '/root/.ssh'.
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:
SHA256:qgc6dnL7BFeNCzbMC3MJ2/mWUfJ74J7rIN4t4sXxC8Y root@localhost.localdomain
The key's randomart image is:
+---[RSA 3072]----+
| . . . |
| * o * |
| + @ + + |
| = * = o |
| . o S o . |
| .o = + o |
| . .+ E + |
| = o+o=.+ o |
| . =o=+..o= |
+----[SHA256]-----+
spawn ssh-copy-id root@192.168.216.179
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '192.168.216.179 (192.168.216.179)' can't be established.
ECDSA key fingerprint is SHA256:gkMCzwLaISQUrSVhbQrfQfP3iKhVouSKK8Y8y0mr3SY.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@192.168.216.179's password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh '[email protected]'"
and check to make sure that only the key(s) you wanted were added.
[root@localhost ~]# ssh 192.168.216.179
Last login: Sat Oct 23 09:15:42 2021 from 192.168.216.1
满足正常使用