git的问题，从远程的github上复制仓库失败？是什么原因，求解答

Question

$ git clone https://github.com/yekongliu/...Cloning into 'yekongliu.github.io'...fatal: unable to access 'https://github.com/yekongliu/...': Couldn't resolve host 'github.com'是本地的git没有配置正确的原因吗？