有源仓库 阿里云镜像官方站点

https://developer.aliyun.com/mirror/

mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup


wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-8.repo

或者

curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-8.repo


[23:36:42 root@C8[ network-scripts]#yum makecache
Repository AppStream is listed more than once in the configuration
Repository extras is listed more than once in the configuration
Repository PowerTools is listed more than once in the configuration
Repository centosplus is listed more than once in the configuration
CentOS-8 - AppStream                                           2.2 kB/s | 4.3 kB     00:01
CentOS-8 - Base - mirrors.aliyun.com                           1.7 MB/s | 2.2 MB     00:01
CentOS-8 - Extras - mirrors.aliyun.com                          20 kB/s | 5.5 kB     00:00
Metadata cache created.