Linux日常运维-SSHD(一)

# 输入该命令后，一直按回车即可。
# 这里也可以添加许多参数，甚至可以设置密钥的密码。
[root@localhost ~]# 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:
SHA256:4jzW3nqWv4wxN7j4v0LjFI+DUuYFVQ1xeiS6fUF3yGo root@localhost.localdomain
The key's randomart image is:
+---[RSA 2048]----+
|         ...==+.o|
|        .  . *+..|
|         .. ..o  |
|        o ooE. . |
|      .+So.=. .  |
|     o.oo *...   |
|      =..+++o    |
|     . o o*B .   |
|        +==+*o   |
+----[SHA256]-----+

[root@localhost]# ls -l /root/.ssh/
总用量 8
-rw-------. 1 root root 1675 6月  28 22:57 id_rsa     //私钥
-rw-r--r--. 1 root root  408 6月  28 22:57 id_rsa.pub //公钥

# 需要输入对方服务器的密码
# 也可以手动将id_rsa.pub文件的内容放到/root/.ssh/authorized_keys中，注意权限
# 我们将公钥传输到108服务器后，就可以无密码登录108服务器了
[root@localhost .ssh]# ssh-copy-id 192.168.179.108
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '192.168.179.108 (192.168.179.108)' can't be established.
ECDSA key fingerprint is SHA256:KcCHSnldK0xz0g82jmvKQ5bFYI8Wn04rPYbmK94nwhQ.
ECDSA key fingerprint is MD5:f3:3b:6d:09:54:06:57:b0:13:3a:75:e1:ca:79:70:bd.
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@192.168.179.108's password: 
Number of key(s) added: 1
<p>Now try logging into the machine, with:   "ssh '192.168.179.108'"
and check to make sure that only the key(s) you wanted were added.

# 虽然公钥在原始服务器的名字和内容是/root/.ssh/id_rsa.pub，但在复制到新服务器后名字会变成authorized_keys</p><h1>如果该服务器允许多个其他机器无密码登录，则该文件会有多行。</h1><p>[root@localhost .ssh]# cd /root/.ssh/
[root@localhost .ssh]# ls -l
总用量 4
-rw-------. 1 root root 408 6月  28 23:02 authorized_keys

# 未输入密码，也可以直接登录。</p><h1>登录时，它会读取本地的私钥和服务器中的公钥进行验证，验证通过则登录成功。</h1><p>[root@localhost .ssh]# ssh 192.168.179.108
Last login: Fri Jun 28 23:09:05 2024 from 192.168.179.1
[root@localhost ~]#