Centos如何使用SSH遠程鏈接主機

ssh有兩種鏈接方式

第一種：密碼認證鏈接方式

 

[root@admin ~]# ssh root@192.168.1.25 (服務端的ip回車提示以下）
The authenticity of host '192.168.1.250 (192.168.1.250)' can't be established.
RSA key fingerprint is 75:f9:55:3b:da:0d:38:b2:c6:1b:e9:18:96:97:8a:2e.
Are you sure you want to continue connecting (yes/no)?（這裏輸入yes保證密鑰回車）

Warning: Permanently added '192.168.1.250' (RSA) to the list of known hosts.
root@192.168.1.25's password:（輸入密碼回車）

第二種：密鑰鏈接方式

 

[root@admin ~]# ssh-keygen（啓動密鑰鏈接方式）
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): (保持密鑰的地方默認是保

                                                          存在當前用戶目錄下如需

                                                           修改，輸入保持地址）
Enter passphrase (empty for no passphrase): （是否使用密碼使用默認回車）
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:
e4:4d:4c:b7:e4:ec:07:d5:a7:f0:3c:a0:b0:1f:98:a1 root@admin
The key's randomart p_w_picpath is:
+--[ RSA 2048]----+
|          . o .. |
|        oo =oo  o|
|       ..*o.== ..|
|      Eo+oo. .=  |
|        S.... .. |
|          .  .   |
|                 |
|                 |
|                 |
+-----------------+

密鑰生成以後進入.ssh/目錄會看到

 

[root@admin ~]# cd .ssh/
[root@admin .ssh]# ls
id_rsa  id_rsa.pub  known_hosts（id_rsa.pub)這個文件就是密鑰認證文件

[root@admin .ssh]# ssh-copy-id -i id_rsa.pub root@192.168.1.25(把密鑰發送給服務端）
root@192.168.1.25's password:（輸入服務端密碼）輸入回車提示以下就成功了

Now try logging into the machine, with "ssh 'root@192.168.1.25'", and check in:

  .ssh/authorized_keys

to make sure we haven't added extra keys that you weren't expecting.

備註：若是系統裝或發生其它不能正常鏈接的狀況把.ssh/目錄下的文件刪除從新配置便可

 

若是想比較安全或控制用戶登陸進入cd /etc/ssh會看到

[root@admin .ssh]# cd /etc/ssh
[root@admin ssh]# ls
moduli       ssh_host_dsa_key      ssh_host_key.pub
ssh_config   ssh_host_dsa_key.pub  ssh_host_rsa_key
sshd_config  ssh_host_key          ssh_host_rsa_key.pub

ssh_config這個是客戶端配置文件不用管，sshd_config這個是服務端配置文件修改這個就行

用vim打開ssh_config

 

SyslogFacility AUTHPRIV
#LogLevel INFO

# Authentication:

#LoginGraceTime 2m
#PermitRootLogin yes(把這個改爲no禁止用root登陸）
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10

 

# To disable tunneled clear text passwords, change to no here!#PasswordAuthentication yes#PermitEmptyPasswords noPasswordAuthentication yes（打這個改爲no不能使用密碼驗證）