CentOS系统更换软件安装源
第一步：备份原镜像文件，以免出错后可以恢复。
cp -r /etc/yum.repos.d/ /etc/yum.repos.d.bak/
第二步：下载新的CentOS-Base.repo 到/etc/yum.repos.d/
curl -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo(可能不好用)
第三步：运行yum makecache生成缓存
yum clean all
yum makecache
阿里云epel.repo
[epel] name=Extra Packages for Enterprise Linux 7 - $basearch baseurl=http://mirrors.aliyun.com/epel/7/$basearch failovermethod=priority enabled=1 gpgcheck=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7 [epel-debuginfo] name=Extra Packages for Enterprise Linux 7 - $basearch - Debug baseurl=http://mirrors.aliyun.com/epel/7/$basearch/debug failovermethod=priority enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7 gpgcheck=0 [epel-source] name=Extra Packages for Enterprise Linux 7 - $basearch - Source baseurl=http://mirrors.aliyun.com/epel/7/SRPMS failovermethod=priority enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-7 gpgcheck=0
标签：epel,repo,mirrors,basearch,CentOS7,etc,阿里,yum From： https://www.cnblogs.com/panzhaohui/p/16948441.html