Windows7下Vagrant 启动失败的问题：lib/vagrant/util/io.rb

最近vagrant不知道什么原因无法启动，日志如下：

Bringing machine 'default' up with 'virtualbox' provider...
/Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/io.rb:32:in `encode': "x8B" followed by "x02" on GBK (Encoding::InvalidByteSequenceError)

from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/io.rb:32:in `read_until_block'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/subprocess.rb:194:in `block in execute'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/subprocess.rb:192:in `each'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/subprocess.rb:192:in `execute'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/subprocess.rb:22:in `execute'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/powershell.rb:174:in `version'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/powershell.rb:195:in `validate_install!'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/powershell.rb:96:in `execute_cmd'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/platform.rb:145:in `block (2 levels) in windows_hyperv_enabled?'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/platform.rb:142:in `each'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/platform.rb:142:in `block in windows_hyperv_enabled?'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/platform.rb:153:in `windows_hyperv_enabled?'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/plugins/providers/virtualbox/action/check_virtualbox.rb:19:in `call'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/action/warden.rb:34:in `call'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/action/builder.rb:116:in `call'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/action/runner.rb:66:in `block in run'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/util/busy.rb:19:in `busy'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/action/runner.rb:66:in `run'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/machine.rb:239:in `action_raw'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/machine.rb:208:in `block in action'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/environment.rb:614:in `lock'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/machine.rb:194:in `call'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/machine.rb:194:in `action'
    from /Vagrant/embedded/gems/2.2.1/gems/vagrant-2.2.1/lib/vagrant/batch_action.rb:82:in `block (2 levels) in run'

参考了两篇网上找到文章，无法解决问题

1 日文网站的解决方案（**认为是编码问题**）：https://github.com/NetCommons3/NetCommons3/issues/50
        対策
        「C:\opscode\chefdk\bin\berks」 を開き、3行目に
        Encoding.default_external = 'utf-8'
 2 laravel-china上的一篇文章（**认为是中文问题**），很相似，可是问题原因不同。但也给了解决思路
        https://laravel-china.org/articles/4082/a-wonderful-problem-encountered-in-the-use-of-vagrant

随后自己仔细看了下ruby的日志及相关源码，发现里面描述了powershell的问题，于是尝试启动windows的powershell果然是启动失败。
这样的话问题就好说了，解决了powershell的问题就行了。（是.netFramework的问题，原来是自己之前由于visio安装不上，升级了.netFramework）。降级.netFramework即可

之后Vagrant启动正常

总结：遇到问题注意看日志，尽管是自己不熟悉的语言。

文章结尾奶一下ruby：

借用《Programming Ruby》推荐序中的一段话：

事实上，执行性能与开发效率是软件开发中的一对矛盾，所有的程序设计语言都必须面对这个矛盾，作出自己的选择。 
　　
在当时，大多数新语言的选择是上下通吃。它们一方面提供了丰富多彩的高级抽象，另一方面又提供了强有力的底层操作能力，希望由此实现高性能与高效率的统一。
C++、Java、C#和Delphi都是走的这条路线，甚至VB从5.0开始也强化了底层操作机制，并提供了编译模型，不落人后。 
　　
Ruby实现了最纯粹意义上的面向对象，让Smalltalk、Perl和Lisp的灵魂在新的躯壳里高歌。
相比于Python，Ruby的思想更加清晰一致，形式更加灵活；
相比于Perl，Ruby更简单质朴，绝少光怪陆离之举；
相比于Smalltalk和Lisp，Ruby更富有现代感和实干气质；
相比于庙堂之上的“工业语言”，Ruby自由挥洒、轻快锐利；
而相比于JavaScript和PHP，Ruby从Smalltalk继承而来的深厚底蕴又大占优势。

面对执行性能与开发效率的谜题，Ruby毫不犹豫地选择了开发效率，选择了对人脑的友好。

Created by suyaqiang (sueeing@126.com) on 2019/1/20.