As announced and scheduled, several centos services are going to be out of service for about 48 hours since March 14th, 13:00 UTC:
The list of involved services includes https://cbs.centos.org (Koji).
Our stable release tracker rpm ( http://resources.ovirt.org/pub/yum-repo/ovirt-release41.rpm ) requires packages from there and so oVirt from stable release is currently not installable as well on Centos based systems.
name=CentOS-7 - oVirt 4.1
name=CentOS-7 - oVirt common