git clone fatal: unable to access 'https://github.com/carlon/demo.git/': Failed to connect to githu...

虽然之前没有设置代理，但是不知道为什么执行以下代码之后就可以执行Git clone了 

$ git config --global http.proxy
 
 
$ git config --global --unset http.proxy

 报错：ssh_dispatch_run_fatal: Connection to 192.168.1.235 port 22: Broken pipe

解决方案：在~/.ssh目录新建文件config

vi ~/.ssh/config
 
#Added lines to fix.
Host *
IPQoS lowdelay throughput
#end of new file edit

添加权限，不然会报错

chmod 644 ~/.ssh/config