1、安装
直接引用官方版本即可
2、配置（官方镜像安完啥也没有）
初始化yum
cd /etc/yum.repos.d/
sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS-*
sed -i 's|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g' /etc/yum.repos.d/CentOS-*
#不能用 wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo
curl https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo >1.txt
mv 1.txt CentOS-Base.repo
yum clean all
yum makecache
yum install wget -y