ERROR 22 - "The requested URL returned error: 404 Not Found"
看这篇博客，我直接复制了，感谢博主，
http://blog.itblood.com/3681.html
[centos-office] name=centos-office failovermethod=priority baseurl=https://vault.centos.org/6.10/os/x86_64/ gpgcheck=1 gpgkey=https://vault.centos.org/6.10/os/x86_64/RPM-GPG-KEY-CentOS-6
网上捣鼓了半天没弄懂，最后把/etc/yum.repos.d 里只留了一个 CentOS-Base.repo -Base是从网上获取文件
CentOS-Base.repo 里面的内容为
yum install tree :
