Linux allows you to access an ISO image, rather than having to burn a CD or DVD. Keep in mind that the image will be read-only.
Assuming your ISO image is in ~/Downloads/ and you have a directory called /media/cdrom (these are usually created automatically during the install)
You can achieve this using the following command.
mount -o loop ~/Downloads/CentOS-7-x86_64-DVD-1708.iso /media/cdrom