这里有很多很好的答案，我不能全部读完，但是，我只是来给我的一点贡献。我有两个不同的问题:

vagrant up wasn't able to find my ssh 'id_rsa' (because I didn't have it yet, at that time): I ran ssh-keygen -t rsa -b 4096 -C "myemailaddress@mydomain.com", based on this GitHub's article, and voilá, steped through that; Then, I got the same problem of this question "Warning: Connection timed out. Retrying...", eternally...: So, after reading a lot, I've restarted my system and looked at my BIOS (F2 to get there, on PC), and there were Virtualization disabled. I've enabled that, saved, and started the system once again, to check if it has changed anything.

从那以后，流浪起来就像有魔力一样!现在是凌晨4点，但它还在跑!多酷啊，hã?我知道很少有像我这样的受虐狂开发者会在Windows上尝试这个，特别是在Windows 10上，我只是无法不忘记来这里并留下我的话…另一个重要的信息，是，我试图设置Laravel 5，使用Homestead, VirtualBox，作曲家等。这是有效的。所以，希望这个答案能对你有所帮助，就像这个问题和答案对我有所帮助一样。祝福你。G-bye !

我对这个问题的解决方案是，我的旧笔记本电脑启动时间太长了。我打开虚拟盒子，连接到盒子，等待屏幕加载。花了大约8分钟。

然后它连接并安装了我的文件夹，继续运行。

有时候要有耐心!

如果你不想启用GUI，然后不得不禁用它，你也可以从Oracle安装扩展包:

http://www.oracle.com/technetwork/server-storage/virtualbox/downloads/index.html#extpack

然后把这个放在你的Vagrantfile中来启用VRDP:

vb.customize ["modifyvm", :id, "--vrde", "on"]

现在您可以使用RDP按需连接到您的盒子，而不需要运行SSH或一直打开GUI。

我在一台Windows 8.1的机器上遇到了同样的问题。连接超时和启用gui根本没有用，屏幕是黑色的。在我的情况下，修复是禁用“超V”

引用自Vagrant文档https://docs.vagrantup.com/v2/hyperv/index.html

警告:启用Hyper-V将导致VirtualBox、VMware和任何其他虚拟化技术不再工作。请参阅这篇博客文章https://www.hanselman.com/blog/SwitchEasilyBetweenVirtualBoxAndHyperVWithABCDEditBootEntryInWindows81.aspx，如果有需要其他管理程序的时候，可以简单地创建一个引导条目来启动没有启用Hyper-V的Windows。

我在《Vagrant 1.6.5》和《Virtual Box 4.3.16》中也遇到了同样的问题。 在https://github.com/mitchellh/vagrant/issues/4470上描述的解决方案对我来说很好，我只需要删除VirtualBox 4.3.16并安装旧版本4.3.12。

我通过在/etc/fstab中添加一个新条目来测试我的vagrant VM中挂载的文件夹。后来我注销了，跑了个流浪汉，但当我跑了个流浪汉，我得到:

SSH auth method: private key
Warning: Remote connection disconnect. Retrying...

I read all these posts and tried all the ones that seemed relevant for my case (except for vagrant destroy, which would have certainly fixed my problem, but was a last resort in my case). The post by @Kiee gave me the idea to try to boot my VM directly from the VirtualBox GUI. During the boot process the VM halted itself and was asking me if I wanted to skip mounting the test folder that I had added earlier to /etc/fstab. (That's why vagrant couldn't boot the VM.) After answering 'NO' the VM booted no problem. I logged in, removed the naughty line from my fstab, and shutdown the VM.

在那之后，流浪汉就能很好地踢足球了。

外卖吗?如果突然间vagrant无法引导回您的VM，请尝试直接从提供商引导(在我的情况下是VirtualBox)。您的引导可能挂起了与SSH完全无关的东西。