记录学习云计算第六天_腾讯云scretld-优快云博客

本文链接：https://blog.youkuaiyun.com/2301_76281519/article/details/142916684

1、免密登录

1、在服务器A上生成一对密钥
[root@server-1 ~]# ssh-keygen
Generating public/private rsa key pair.
# 生成的密钥对默认保存的位置
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:y8NF/DbgK9m1S+JahBVlGSIP7qXGlFo0Cgk79i18SUA root@server-1
The key's randomart image is:
+---[RSA 2048]----+
| .oE. = o.+o |
| ..o + B +. |
| + o = B |
| . + o B B o |
| + = S + = |
| o + * + o |
| B = o |
| = o . |
| ... . |
+----[SHA256]-----+

[root@server-1 ~]# ls /root/.ssh/
id_rsa id_rsa.pub known_hosts

id_rsa.pub 生成的公钥文件
id_rsa 生成的私钥文件
known_hosts 首次远程登录其他服务器保存的远程服务器的公钥

2、将公钥拷贝给另一个服务器
[root@server-1 ~]# ssh-copy-id 192.168.1.102
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '192.168.1.102 (192.168.1.102)' can't be established.
ECDSA key fingerprint is SHA256:FOjAVNiEZDE1Fsyc2IlnrjfC1G4Z3UpWthHVqBki5uo.
ECDSA key fingerprint is MD5:bb:7a:73:a8:f7:ab:52:eb:ab:cc:b6:93:39:f4:11:56.
Are you sure you want to continue connecting (yes/no)? 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@192.168.1.102's password:

Number of key(s) added: 1

Now try logging into the machine, with: "ssh '192.168.1.102'"
and check to make sure that only the key(s) you wanted were added.

[root@server-1 ~]# ssh 192.168.1.102
Last login: Thu Mar 21 20:59:38 2024 from bogon

# 查看第二台服务器中保存的公钥信息
[root@bogon ~]# cat /root/.ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDBMsxREekrxcAtfJzbJmRi373Qsm/Y6MIsaVg9iiUudmV7Z5WKiqyHiamu/e1/2aBRNcVy0LYeJxPhpkCPBgke34Cah7z7JqLeMLOByatCl6EvIibnIQhWytkGqE5zsPE6kcuxY+J+HysLwDrOfv1CMw/I/gJLJ3QiViF1Lmt2fQEQ7CnWtEBv038aJ8ieiuzxcpIUHEsJu6GYjF+BAOwiZ7WvnQxHUKrkv7aPhLBf/kNc72qGGkviFYAw3FBBHvOyaO69SoBmjM4fejhnwypTCyn7nbWirlDz8OWWiUvEFGdxLtCs0AiZ/2m0twYzZFQRJJymAbOmEJpn4iQF7/Gd root@server-1

2、配置远程登录欢迎信息

1、配置输入密码前的登录信息
当前输入用户后，并没有显示任何欢迎信息，而是直接弹出输入密码提示。
[root@server-1 ~]# ssh 192.168.1.102
root@192.168.1.102's password:

2、修改sshd配置文件,/etc/ssh/banner 里面定义了欢迎的信息
[root@server-1 ~]# vi /etc/ssh/sshd_config
Banner /etc/ssh/banner

3、定义欢迎的信息
[root@server-1 ~]# vi /etc/ssh/banner

_oo0oo_
088888880
88" . "88
(| -_- |)
0\ = /0
___/'---'\___
.' \\\\| |// '.
/ \\\\||| : |||// \\
/_ ||||| -:- |||||- \\
| | \\\\\\ - /// | |
| \_| ''\---/'' |_/ |
\ .-\__ '-' __/-. /
___'. .' /--.--\ '. .'___
."" '< '.___\_<|>_/___.' >' "".
| | : '- \'.;'\ _ /';.'/ - ' : | |
\ \ '_. \_ __\ /__ _/ .-' / /
====='-.____'.___ \_____/___.-'____.-'=====
'=---='

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
佛祖保佑 iii 永不宕机

4、重启sshd服务
[root@server-1 ~]# systemctl restart sshd

5、使用其他服务器测试登录本服务器
[root@bogon ~]# ssh 192.168.1.101

_oo0oo_
088888880
88" . "88
(| -_- |)
0\ = /0
___/'---'\___
.' \\\\| |// '.
/ \\\\||| : |||// \\
/_ ||||| -:- |||||- \\
| | \\\\\\ - /// | |
| \_| ''\---/'' |_/ |
\ .-\__ '-' __/-. /
___'. .' /--.--\ '. .'___
."" '< '.___\_<|>_/___.' >' "".
| | : '- \'.;'\ _ /';.'/ - ' : | |
\ \ '_. \_ __\ /__ _/ .-' / /
====='-.____'.___ \_____/___.-'____.-'=====
'=---='

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
佛祖保佑 iii 永不宕机
root@192.168.1.101's password:
Last login: Thu Mar 21 21:15:40 2024 from server-2
[root@server-1 ~]#

1、配置输入密码后的欢迎信息
可以修改 /etc/motd 文件，定义 ssh 成功登录后的欢迎信息。
[root@server-1 ~]# vi /etc/motd
⠰⢷⢿⠄
⠀⠀⠀⠀⠀⣼⣷⣄
⠀⠀⣤⣿⣇⣿⣿⣧⣿⡄
⢴⠾⠋⠀⠀⠻⣿⣷⣿⣿⡀
🏀 ⠀⢀⣿⣿⡿⢿⠈⣿
⠀⠀⠀⢠⣿⡿⠁⠀⡊⠀⠙
⠀⠀⠀⢿⣿⠀⠀⠹⣿
⠀⠀⠀⠀⠹⣷⡀⠀⣿⡄
⠀⠀⠀⠀⣀⣼⣿⠀⢈⣧
2、使用其他服务器测试登录本服务器
[root@bogon ~]# ssh 192.168.1.101

_oo0oo_
088888880
88" . "88
(| -_- |)
0\ = /0
___/'---'\___
.' \\\\| |// '.
/ \\\\||| : |||// \\
/_ ||||| -:- |||||- \\
| | \\\\\\ - /// | |
| \_| ''\---/'' |_/ |
\ .-\__ '-' __/-. /
___'. .' /--.--\ '. .'___
."" '< '.___\_<|>_/___.' >' "".
| | : '- \'.;'\ _ /';.'/ - ' : | |
\ \ '_. \_ __\ /__ _/ .-' / /
====='-.____'.___ \_____/___.-'____.-'=====
'=---='

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
佛祖保佑 iii 永不宕机
root@192.168.1.101's password:
Last login: Thu Mar 21 21:21:40 2024 from server-2

⠰⢷⢿⠄
⠀⠀⠀⠀⠀⣼⣷⣄
⠀⠀⣤⣿⣇⣿⣿⣧⣿⡄
⢴⠾⠋⠀⠀⠻⣿⣷⣿⣿⡀
🏀 ⠀⢀⣿⣿⡿⢿⠈⣿
⠀⠀⠀⢠⣿⡿⠁⠀⡊⠀⠙
⠀⠀⠀⢿⣿⠀⠀⠹⣿
⠀⠀⠀⠀⠹⣷⡀⠀⣿⡄
⠀⠀⠀⠀⣀⣼⣿⠀⢈⣧
[root@server-1 ~]#

3、打包压缩

文件打包
语法 tar -cvf $打包之后的名字 $要打包的文件或者目录
案例：将/etc目录打包为 etc.tar, 打包通常以 .tar 结尾
[root@server-1 ~]# tar -cvf etc.tar /etc
-c 创建一个新的归档
-v 详细列出已处理的文件，显示打包过程
-f 使用归档文件

# 在当前目录会多出一个etc.tar的包
[root@server-1 ~]# ls
anaconda-ks.cfg cmatrix-1.2a cmatrix-1.2a.tar.gz etc.tar ifcfg-ens33 passwd

# 对比打包后的文件与源文件的大小
[root@server-1 ~]# ll -h
total 29M
-rw-------. 1 root root 1.3K Oct 17 19:58 anaconda-ks.cfg
drwxrwxrwx. 2 500 500 4.0K Mar 14 14:43 cmatrix-1.2a
-rw-r--r--. 1 root root 73K Apr 1 2002 cmatrix-1.2a.tar.gz
-rw-r--r-- 1 root root 29M Mar 21 16:11 etc.tar
-rw-r--r--. 1 root root 404 Mar 14 14:08 ifcfg-ens33
-rw-r--r--. 1 root root 798 Mar 20 11:56 passwd

# 查看/etc目录大小
[root@server-1 ~]# du -sh /etc
32M /etc

# 解包
# 语法： tar -xvf $包名
[root@server-1 ~]# tar -xvf etc.tar

# 打包并压缩，压缩格式为gzip，文件后缀一般为 .tar.gz
-z 使用gzip格式进行压缩
[root@server-1 ~]# tar -czvf etc.tar.gz /etc/
[root@server-1 ~]# ll -h
total 11M
-rw-------. 1 root root 1.3K Oct 17 19:58 anaconda-ks.cfg
drwxrwxrwx. 2 500 500 4.0K Mar 14 14:43 cmatrix-1.2a
-rw-r--r--. 1 root root 73K Apr 1 2002 cmatrix-1.2a.tar.gz
-rw-r--r-- 1 root root 10M Mar 21 16:28 etc.tar.gz
-rw-r--r--. 1 root root 404 Mar 14 14:08 ifcfg-ens33
-rw-r--r--. 1 root root 798 Mar 20 11:56 passwd
[root@server-1 ~]# du -sh /etc/
32M /etc/

# 解压缩
[root@server-1 ~]# tar -xf etc.tar.gz

# 生成一个10G大文件
[root@server-1 ~]# dd if=/dev/zero of=/test.txt bs=1024M count=10
10+0 records in
10+0 records out
10737418240 bytes (11 GB) copied, 70.9733 s, 151 MB/s

# 使用gzip单独压缩一个文件
# 语法： gzip $filename，压缩后默认源文件会被删除
[root@server-1 ~]# gzip /test.txt
[root@server-1 ~]# ll -h /test.txt*
-rw-r--r-- 1 root root 10M Mar 21 20:43 /test.txt.gz

# gzip解压缩，解压缩后默认压缩文件会被删除
[root@server-1 ~]# gzip -d /test.txt.gz
[root@server-1 ~]# ll -h /test.txt*
-rw-r--r-- 1 root root 10G Mar 21 20:43 /test.txt