VBoxManage storageattach CentOS-6.4-x86_64-minimal

Assign virtual DVD drive
Like the virtual hard disk, assign a virtual DVD drive. The installation media specifies Cent-6.4- x86 – minimal.iso.

$ VBoxManage storageattach CentOS-6.4-x86_64-minimal --storagectl SATA --port 2 --type dvddrive --medium I:/ISO/CentOS/CentOS-6.4-x86_64-minimal.iso

$ VBoxManage storageattach ${guest-os} \
  --storagectl IDE \
  --port 1 \
  --device 0 \
  --type dvddrive \
  --medium ${iso}