最近在安装SASS的时候，用到gem命令，但是运行出行如下错误！
C:\Users\len>gem install sass
ERROR: While executing gem ... (Gem::RemoteFetcher::FetchError)
Errno::ETIMEDOUT: A connection attempt failed because the connected party di
d not properly respond after a period of time, or established connection failed
because connected host has failed to respond. - connect(2) for "rubygems.global.
ssl.fastly.net" port 443 (https://api.rubygems.org/quick/Marshal.4.8/sass-3.4.13
.gemspec.rz)原因是ruby 的gem被和谐了，现在淘宝的ruby工程师架设了rubygems的国内镜像。使用方法如下：
$ gem sources --remove https://rubygems.org/
$ gem sources -a https://ruby.taobao.org/
$ gem sources -l
*** CURRENT SOURCES ***
https://ruby.taobao.org然后在运行gem命令就可以了！
C:\Users\len>gem install sass
Fetching: sass-3.4.13.gem (100%)
Successfully installed sass-3.4.13
Parsing documentation for sass-3.4.13
Installing ri documentation for sass-3.4.13
Done installing documentation for sass after 5 seconds
1 gem installed