使用yum时一直提示下面的信息
Loaded plugins: fastestmirror
Repository base is listed more than once in the configuration
Repository updates is listed more than once in the configuration
Repository extras is listed more than once in the configuration
Repository centosplus is listed more than once in the configuration
Repository contrib is listed more than once in the configuration
Cleaning repos: base extras updates
Cleaning up Everything
Cleaning up list of fastest mirrors
升级后在/etc/yum.repos.d增加了新的源，和原有的阿里源冲突了，只要删除这些后增加的源，再yum clean all就好了
CentOS-Base.repo CentOS-Debuginfo.repo CentOS-fasttrack.repo CentOS-Media.repo CentOS-Vault.repo