centos-repo.md

from https://serverfault.com/a/1161847

sed -i s/mirror.centos.org/vault.centos.org/g /etc/yum.repos.d/CentOS-.repo sed -i s/^#.baseurl=http/baseurl=http/g /etc/yum.repos.d/CentOS-.repo sed -i s/^mirrorlist=http/#mirrorlist=http/g /etc/yum.repos.d/CentOS-.repo