fatal: unable to access 'https://github.com/Homebrew/brew/'

fatal: unable to access 'https://github.com/Homebrew/brew/': Could not resolve host: github.com
Failed during: git fetch origin master:refs/remotes/origin/master --tags --force

解决方式:

　　1.试着先在终端 ping github.com

　　MacBook-Pro:~$ ping github.com 

  PING github.com (13.250.177.223): 56 data bytes
  Request timeout for icmp_seq 0
  Request timeout for icmp_seq 1
  Request timeout for icmp_seq 2
  Request timeout for icmp_seq 3

• 如果 ping 出来是这种结果，就接着看第二步

2. 修改 hosts 配置
   • 在终端中 sudo vi /etc/hosts 打开编辑文件
   • 按 s 进入编辑模式
   • 接着在最下面添加 192.30.253.113 github.com