安裝 wget
yum install -y wget
進入目錄
cd /etc/yum.repos.d/
創建目錄
mkdir backup
默認源配備份
mv C* backup/
下載阿里雲yum源
wget -O /etc/yum.repos.d/CenOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo
清除舊緩存
yum clean all
創建新緩存
yum makecache
更新yum
yum update -y