cent换清华源

[李东岳]

sed -e 's|^mirrorlist=|#mirrorlist=|g' \
         -e 's|^#baseurl=http://mirror.centos.org|baseurl=http://mirrors.tuna.tsinghua.edu.cn|g' \
         -i.bak \
         /etc/yum.repos.d/CentOS-*.repo

yum clean all &&
yum makecache