ssh免密登录

一、环境

三台机器做ssh免密登录

用户	IP
test	192.168.10.10
test	192.168.10.20
test	192.168.10.30

二、操作

2.1、生成秘钥

登录192.168.10.10，通过ssh-******生成秘钥，一路回车即可，生成秘钥会在/home/test/.ssh目录中，具体如下：

[@test_192_168_10_10 ~]$ ssh-****** -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/test/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/test/.ssh/id_rsa.
Your public key has been saved in /home/test/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:Ay5uY6M3FAYZnv+rCfPoN+iRGPT6lHIkKRfaR2dV2Ac [email protected]_192_168_10_10
The key's randomart image is:
+---[RSA 2048]----+
|  .o    .+E.     |
| .o.   .. . .    |
| .+.. +    .     |
|.oo+o+ .         |
|+oo++.. S        |
|.+++oo   .       |
|.o=** .          |
|  *X=+ .         |
| o=+++.          |
+----[SHA256]-----+
[@test_192_168_10_10 ~]$ 

其他两台机器同样操作 

2.2、拷贝公钥

将192.168.10.20和192.168.10.30这两台机器生成的公钥拷贝到192.168.10.10，所以需要分别登录192.168.10.20和192.168.10.30，执行如下：

[@test_192.168.10.20 ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub [email protected]
[@test_192.168.10.30 ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub [email protected]

在192.168.10.10机器上面会自动生成该文件: /home/mediaai/.ssh/authorized_keys，文件内容就是192.168.10.20  192.168.10.30的公钥.

将192.168.10.10的公钥加入到authorized_keys文件中，执行下面命令：

[@test_192_168_10_10 ~]$ cd ~/.ssh
[@test_192_168_10_10 ~/.ssh]$ cat id_rsa.pub >> authorized_keys

2.3、将authorized_keys分别拷贝到 192.168.10.20  192.168.10.30的.ssh目录中：

[@test_192_168_10_10 ~/.ssh]$ scp authorized_keys 192.168.10.20:/home/test/.ssh
[@test_192_168_10_10 ~/.ssh]$ scp authorized_keys 192.168.10.30:/home/test/.ssh

三、验证

至此如果没有问题，应该可以完成免密登录