大部分情况下，Homestead 的安装是非常简单的，我就基本上没遇到过问题。然而如果你遇到 vagrant up 后卡在 SSH auth method: private key 的情况，可以按照本文办法进行尝试：

问题

homestead-7: Warning: Host appears down. Retrying...
homestead-7: Warning: Host appears down. Retrying...
homestead-7: Warning: Host appears down. Retrying...
homestead-7: Warning: Host appears down. Retrying...
homestead-7: Warning: Host appears down. Retrying...
homestead-7: Warning: Host appears down. Retrying...

解决办法

重新生成 insecure_private_key，运行

> vagrant ssh-config
Host homestead-7
  HostName 10.211.55.3
  User vagrant
  Port 22
  UserKnownHostsFile /dev/null
  StrictHostKeyChecking no
  PasswordAuthentication no
  IdentityFile /Users/x/Homestead/.vagrant/machines/homestead-7/parallels/private_key
  IdentitiesOnly yes
  LogLevel FATAL
  ForwardAgent yes

移除文件 /Users/x/Homestead/.vagrant/machines/homestead-7/parallels/private_key

vagrant halt
vagrant up