Hi, After setting up dag.repo in /etc/yum.repo, and tried yum update, yum will try to update my system from dag even it is originally from centos.org. The reason for us to choose CentOs instead of Fedora is the stability of the OS. And the reason of getting pacakages from dag is there is something we need, which is not offered by CentOs. If dag packages will overwritten CentOs, surprises may arises. Is there a method that yum only update packages from CentOs if it is originally from CentOs, and update from dag if it is originally from dag? Jason