vagrant 默认是使用用户名和密钥登陆的，之所以在vagrantfile目录输入vagrant ssh可以登陆，是因为vagtant创建虚拟机的时候生成了非对称加密的公私钥，公钥上传到了虚拟机，私钥保存在宿主机中。

查看私钥地址，我们使用ssh连接试一下，我这里已经创建好了一台虚拟机并处于运行状态。

# 查看当前虚拟机的配置，可以看到`PasswordAuthentication no` 密码登陆被禁止，`IdentityFile` 私钥地址
Administrator@ADMINIS-AL9GNP3 MINGW64 /e/code/test/vm/data2
$ vagrant ssh-config
Host default
  HostName 127.0.0.1
  User vagrant
  Port 2222
  UserKnownHostsFile /dev/null
  StrictHostKeyChecking no
  PasswordAuthentication no
  IdentityFile C:/Users/Administrator/.vagrant.d/boxes/traefik_box/0/virtualbox/vagrant_private_key
  IdentitiesOnly yes
  LogLevel FATAL
Administrator@ADMINIS-AL9GNP3 MINGW64 /e/code/test/vm/data2
# 尝试使用密钥文件和用户名登陆
$ ssh -i C:/Users/Administrator/.vagrant.d/boxes/traefik_box/0/virtualbox/vagrant_private_key vagrant@127.0.0.1 -p 2222
Welcome to Ubuntu 16.04.7 LTS (GNU/Linux 4.4.0-210-generic x86_64)
 * Documentation:  https://help.ubuntu.com
 * Management:     https://landscape.canonical.com
 * Support:        https://ubuntu.com/advantage
UA Infra: Extended Security Maintenance (ESM) is not enabled.
0 updates can be applied immediately.
88 additional security updates can be applied with UA Infra: ESM
Learn more about enabling UA Infra: ESM service for Ubuntu 16.04 at
https://ubuntu.com/16-04
Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.
Last login: Thu Jun 16 07:31:35 2022 from 10.0.2.2
vagrant@swarm4:~$

进入虚拟机启动密码登陆

# PasswordAuthentication 修改为yes
sudo sed -i "52c PasswordAuthentication yes"  /etc/ssh/sshd_config
# 重启加载最新配置
sudo service sshd restart

尝试密码登陆成功

Administrator@ADMINIS-AL9GNP3 MINGW64 /e/code/test/vm/data2
$ ssh vagrant@127.0.0.1 -p 2222
vagrant@127.0.0.1's password:
Welcome to Ubuntu 16.04.7 LTS (GNU/Linux 4.4.0-210-generic x86_64)
 * Documentation:  https://help.ubuntu.com
 * Management:     https://landscape.canonical.com
 * Support:        https://ubuntu.com/advantage
UA Infra: Extended Security Maintenance (ESM) is not enabled.
0 updates can be applied immediately.
88 additional security updates can be applied with UA Infra: ESM
Learn more about enabling UA Infra: ESM service for Ubuntu 16.04 at
https://ubuntu.com/16-04
Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.
Last login: Mon Jun 20 06:39:45 2022 from 10.0.2.2
vagrant@swarm4:~$

ssh小技巧

如何愉快的使用ssh登陆虚拟机呢？每次都需要进入vagrantfile目录执行命令执行命令，或者ssh指定密钥/输入密码什么的都挺麻烦。我这里介绍一个简单方法，只需要轻轻的配置一下，就可以愉快的玩耍了。

• 找到宿主机的用户目录下面的.ssh目录，我的是在这里C:\Users\Administrator\.ssh，新建config.txt文件,把vagrant ssh-config输入的配置复制粘贴到config.txt,修改Host为一个自己喜欢的名称。

  Host vagrant-ssh
  HostName 127.0.0.1
  User vagrant
  Port 2222
  UserKnownHostsFile /dev/null
  StrictHostKeyChecking no
  PasswordAuthentication no
  IdentityFile C:/Users/Administrator/.vagrant.d/boxes/traefik_box/0/virtualbox/vagrant_private_key
  IdentitiesOnly yes
  LogLevel FATAL

  登陆测试，可以在任何目录执行此命令，这个命令是全局的，这样就简单多了

  # 使用ssh Host(之前指定的Host)
  Administrator@ADMINIS-AL9GNP3 MINGW64 /e/code/test/vm/data2
  $ ssh vagrant-ssh
  Welcome to Ubuntu 16.04.7 LTS (GNU/Linux 4.4.0-210-generic x86_64)
   * Documentation:  https://help.ubuntu.com
   * Management:     https://landscape.canonical.com
   * Support:        https://ubuntu.com/advantage

• updates can be applied immediately.

• additional security updates can be applied with UA Infra: ESM
  Learn more about enabling UA Infra: ESM service for Ubuntu 16.04 at
  https://ubuntu.com/16-04
  Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
  applicable law.
  Last login: Mon Jun 20 06:44:22 2022 from 10.0.2.2
  vagrant@swarm4:~$