CentOS下yum命令报错File contains no section headers. file: file:///etc/yum.repos.d/

解决方法：

删除原有文件：rm -f /etc/yum.repos.d/CentOS-Base.repo

重新下载：wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo