mkdir -p /mnt/cdrom
mount /dev/cdrom /mnt/cdrom
cd /etc/yum.repos.d/
mkdir backup
mv *.repo backup/
touch CentOS.repo
local="[local]\nname=cdrom\nbaseurl=file:///mnt/cdrom\ngpgcheck=0\nenabled=1\n"
echo -e $local >> CentOS.repo
yum clean all
yum makecache
mountiso="/dev/cdrom /mnt/cdrom\tiso9660\tdefaults\t0 0"
echo -e $mountiso >> /etc/fstab
mount -a