used to be you had to be careful to only enable dag/epel/atrpms/kde-redhat long enough to get something specific, and have them disabled when doing yum update. i presume this is still important, or at least good practice. once you've installed, for example, nagios, and it pulls in some addidional packages from dag/epel, you of course want to keep everything up to date at all times. i'm guessing it's insufficient to just do yum --enablerepo=dag --enablerepo=epel install nagios nagios-plugins without now also explicitly mentioning those additional packages, in case nagios doesn't have an update but some of the addidional packages do, am i right? please clarify whether your answers are applicable to rhel/centos/SL/dag 6/5/4 yum. pointers to clueful writeups especially welcome. tia, -g