实现三台虚拟机间的无密码SSH登录

为了实现三台虚拟机（命名为node01、node02和node03）之间的无密码SSH登录，首先需要在node01上生成SSH密钥对。这可以通过执行以下命令来完成：

[root@node01 ~]# ssh-keygen -t rsa -b 2048
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.

接下来，需要将生成的公钥复制到其他两台虚拟机（node02和node03）上。确保这些机器之间网络互通，能够互相ping通。使用scp命令完成公钥的复制：

[root@node01 ~]# scp /root/.ssh/id_rsa.pub root@192.168.22.130:/root/.ssh/authorized_keys
root@192.168.22.130's password: 

[root@node01 ~]# scp /root/.ssh/id_rsa.pub root@192.168.22.100:/root/.ssh/authorized_keys
The authenticity of host '192.168.22.100 (192.168.22.100)' can't be established.
ECDSA key fingerprint is a2:25:2d:c3:ef:90:24:5b:ab:e3:13:b6:0f:ea:a0:de.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.22.100' (ECDSA) to the list of known hosts.
root@192.168.22.100's password: 

确保node02和node03的/root/.ssh/目录下已存在authorized_keys文件：

[root@node02 ~]# ls /root/.ssh/
authorized_keys  id_rsa  id_rsa.pub  known_hosts

[root@node03 ~]# ls /root/.ssh/
authorized_keys  id_rsa  id_rsa.pub  known_hosts

最后，从node01尝试无密码登录到node02和node03，以验证配置是否成功：

[root@node01 ~]# ssh root@192.168.22.130
Last login: Thu Jan 7 13:44:40 2021 from 192.168.22.1

[root@node02 ~]# exit
登出
Connection to 192.168.22.130 closed.

[root@node01 ~]# ssh root@192.168.22.100
Last login: Thu Jan 7 00:35:18 2021 from 192.168.22.1

同样地，可以在node02和node03之间相互尝试无密码登录，以进一步验证整个配置过程的有效性。