1.先备份原镜像文件
cp -r yum.repos.d/ yum.repos.d.backup
2.下载新的CentOS-Base.repo
到/etc/yum.repos.d/
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.163.com/.help/CentOS7-Base-163.repo
3.把每个baseurl
后边的$releasever
替换成7
,把$basearch
替换成x86_64
#vim文本替换
%s/$releasever/7/g
%s/$basearch/x86_64/g
3.清除原有yum缓存
yum clean all
4.yum makecache
yum makecache