Linux伺服器設定SSH登陸

[[email protected] ~]$ ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/exchange/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/exchange/.ssh/id_rsa.
Your public key has been saved in /home/exchange/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:HwO0jv+tPpO9vfNkGk5qsnWw67UhtdlAB4zqKy3X1Jk 
 
[email protected]
The key's randomart image is:
+---[RSA 2048]----+
|        .    o.  |
|       . .  . .. |
|        o  .  . .|
|       o ..  . . |
|      . S.o ..oo |
|       . ..o.+E= |
|        ...*+ O +|
|        o.Oo+X.B |
|         ==O*.*+.|
+----[SHA256]-----+

再開啟

[[email protected]
 
 ~]$ cd ～/.ssh
[[email protected] .ssh]$ ls
authorized_keys  id_rsa  id_rsa.pub
[[email protected] .ssh]$ ll
total 12
-rw-------. 1 exchange exchange  747 9月  11 18:17 authorized_keys
-rw-------. 1 exchange exchange 1679 9月  18 20:46 id_rsa
-rw-r--r--. 1 exchange exchange  412 9月  18 20:46 id_rsa.pub
 

這裡有兩種做法
1.將伺服器公鑰匯入到 authorized_keys 中，將私鑰下載到客戶端，通過工具連線。

[[email protected] .ssh]$ cat id_rsa.pub >> authorized_keys

把 id_rsa 下載下來
2.電腦端生成 ssh-key，將公鑰發給管理員加到 authorized_keys 檔案中。

上述兩種方法都可以
修改許可權

[[email protected] .ssh]$ chmod 600 authorized_keys 
[[email protected] .ssh]$ chmod 700 ~/.ssh

#修改SSH配置
[[email protected] .ssh]$ sudo vim /etc/ssh/sshd_config 
主要是以下三個：
RSAAuthentication yes    # 啟用 RSA 認證
PubkeyAuthentication yes    # 啟用公鑰認證
PermitRootLogin yes    # 允許root使用者ssh登陸
最後重啟SSH服務
[[email protected] .ssh]$ service sshd restart

儲存之後就可以用ssh 直接登陸了，特別是電腦裝的linux系統，用ssh命令不用輸入密碼，很方便。windows下的ssh 客戶端很多，可能感覺不出來這種方式的便捷。