已知问题
安装ruby之后，重新启动ubuntu on windows，输入ruby命令，提示找不到。
发现的解决办法 执行下面命令
source /home/xxxx/.rvm/scripts/rvm
把xxxx换成自己的用户名
为什么热衷于折腾jekyll呢，因为他们网站下面有句话 GitHub Pages are powered by Jekyll
戳开有惊喜。
环境
使用Ubuntu On Windwos,https://github.com/Microsoft/BashOnWindows了解详细信息
这里讲述怎么打开ubuntuOnWindows（https://msdn.microsoft.com/en-us/commandline/wsl/install_guide）
在使用过程中，感觉这货就像是windows上的一个软件，非常方便。
假如说你把这货玩儿坏了，可以使用命令
lxrun /uninstall /full
进行卸载
然后使用命令
lxrun /install
进行安装。
更多命令参见https://msdn.microsoft.com/en-us/commandline/wsl/reference
安装方法
本来想着在ubuntu上安装ruby，有啥好难的，使用 sudo apt-get install ruby不能就安装好了？
我开始也是这么想的……
如果你看到了这篇文章，没准儿你碰到了跟我一样的问题。
撰写本文时，通过上面的命令，只能安装1.9.3这个版本的，but最新版本的ruby已经2.3了，jekyll也已经嫌弃这个版本了……
然后开始搜索查找怎么解决，费老劲了。
安装ruby
在开搞之前，一定要先把ubuntu的源给修改成国内的源，不然会是非常漫长的过程，具体步骤搜索以下大把的都是
尝试了两种解决方案
1.使用 https://launchpad.net/~brightbox/+archive/ubuntu/ruby-ng这里给出的方案，能够安装，但在使用gem安装的程序过程中，出现找不到命令的问题，应该时哪个地方配置除了问题了，对linux了解不多，没有多费心寻找解决方案。不过看样子应该时可行方案之一。
2.使用rvm安装，Ruby enVironment (Version) Manager (RVM)07年出现的东西，用起来很省心，中间需要两次输入密码进行授权。https://rvm.io/rvm/install有安装教程，我用的这个。
ruby安装完成之后，需要安装ruby-dev，执行命令 rvm install ruby-dev就能安装好了
安装jekyll
http://jekyllrb.com/
直接照着上面的安装就好了，新版本的貌似要安装bundler，不知道干啥用的。
只使用命令 jekyll server --force 看起来一样正常 。
这里最好把gem的源设置成国内的，不然可能会碰到伟大的长城。
我用的是这个 http://mirrors.aliyun.com/rubygems/
下面是具体设置步骤
gem sources --remove https://rubygems.org/
gem sources -a https://ruby.taobao.org/ 据说淘宝的已经停止维护了，ssl证书貌似除了问题
gem sources --add http://mirrors.aliyun.com/rubygems/
gem sources -l
异常处理
bundle install时如果碰到以下错误
Error details
ArgumentError: parent directory is world writable but not sticky
/home/ubuntu/.rvm/rubies/ruby-2.3.0-dev/lib/ruby/2.3.0/tmpdir.rb:93:in `ensure in mktmpdir'
/home/ubuntu/.rvm/rubies/ruby-2.3.0-dev/lib/ruby/2.3.0/tmpdir.rb:95:in `mktmpdir'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/vendor/compact_index_client/lib/compact_index_client/updater.rb:29:in `update'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/vendor/compact_index_client/lib/compact_index_client.rb:64:in `update'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/vendor/compact_index_client/lib/compact_index_client.rb:55:in `update_and_parse_checksum
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/fetcher/compact_index.rb:65:in `available?'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/fetcher/compact_index.rb:15:in `call'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/fetcher/compact_index.rb:15:in `block in compact_index_request'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/fetcher.rb:154:in `use_api'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/source/rubygems.rb:331:in `block in api_fetchers'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/source/rubygems.rb:331:in `select'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/source/rubygems.rb:331:in `api_fetchers'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/source/rubygems.rb:336:in `block in remote_specs'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/index.rb:10:in `build'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/source/rubygems.rb:335:in `remote_specs'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/source/rubygems.rb:82:in `specs'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/definition.rb:211:in `block (2 levels) in index'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/definition.rb:209:in `each'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/definition.rb:209:in `block in index'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/index.rb:10:in `build'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/definition.rb:206:in `index'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/definition.rb:200:in `resolve'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/definition.rb:140:in `specs'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/definition.rb:129:in `resolve_remotely!'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/installer.rb:195:in `resolve_if_need'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/installer.rb:70:in `run'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/installer.rb:22:in `install'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/cli/install.rb:102:in `run'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/cli.rb:175:in `install'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/vendor/thor/lib/thor/invocation.rb:126:in `invoke_command'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/vendor/thor/lib/thor.rb:359:in `dispatch'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/vendor/thor/lib/thor/base.rb:440:in `start'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/cli.rb:11:in `start'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/exe/bundle:27:in `block in <top (required)>'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/lib/bundler/friendly_errors.rb:98:in `with_friendly_errors'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/gems/bundler-1.12.5/exe/bundle:19:in `<top (required)>'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/bin/bundle:23:in `load'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/bin/bundle:23:in `<main>'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/bin/ruby_executable_hooks:15:in `eval'
/home/ubuntu/.rvm/gems/ruby-2.3.0-dev/bin/ruby_executable_hooks:15:in `<main>'
Environment
Bundler 1.12.5
Rubygems 2.5.1
Ruby 2.3.0p0 (2015-12-25 revision 53290) [x86_64-linux]
GEM_HOME /home/ubuntu/.rvm/gems/ruby-2.3.0-dev
GEM_PATH /home/ubuntu/.rvm/gems/ruby-2.3.0-dev:/home/ubuntu/.rvm/gems/ruby-2.3.0-dev@global
RVM 1.27.0 (latest)
Git 1.9.1
rubygems-bundler (1.4.4)
尝试使用 find ~/.bundle/cache -type d -exec chmod 0755 {} +，参考 https://github.com/bundler/bundler/issues/4599
jekyll server时如果你遇到如下错误
jekyll 3.2.1 | Error: Invalid argument - Failed to watch ".sass-cache/5273553f1fac615ec884d08d8e7307b8700e1583": the given event mask contains no legal events; or fd is not an inotify file descriptor.
尝试使用 jekyll server --force ,参考 https://github.com/jekyll/jekyll/issues/5233