[psbuild@c4build64 ~]$ cat /etc/yum.conf
[main]
cachedir=/var/cache/yum
debuglevel=2
logfile=/var/log/yum.log
pkgpolicy=newest
distroverpkg=centos-release
tolerant=1
exactarch=1
retries=20
obsoletes=1
gpgcheck=1

# PUT YOUR REPOS HERE OR IN separate files named file.repo
# in /etc/yum.repos.d
[psbuild@c4build64 ~]$ rpm -V centos-release
S.5....T  c /etc/yum.repos.d/CentOS-Base.repo
S.5....T  c /etc/yum.repos.d/CentOS-Media.repo
[psbuild@c4build64 ~]$