Here is my final Script
At first Insert Your RHEL 6.3 or Scientific Linux 6.3 or Centos 6.3 DVD your DVD ROM
# df -h [show where your dvd are mounted,i used here /dev/sr0 to /mnt]
please copy this script and Save as
yum.sh
after save this script plz set permission
#chmod +x yum.sh
#./yum.sh
df -h
cd /etc/yum.repos.d/
rm -rf *
touch /etc/yum.repos.d/rhel6.repo
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