• Clone a virtual disk image:

    $ VBoxManage clonehd original-disk.vdi copy.vdi

  • Resize a virtual disk image to 20 Gb:

    $ VBoxManage modifyhd disk.vdi --resize 20000

  • Convert a VirtualBox image to a raw image:

    $ VBoxManage clonehd --format RAW disk.vdi disk.raw

  • Convert a raw image to a VirtualBox image:

    $ VBoxManage convertdd disk.raw disk.vdi --format VDI

  • List virtual machines:

    $ VBoxManage list vms

  • Fix broken NAT (source):

    $ VBoxManage modifyvm "name" --natdnshostresolver1 on
$ VBoxManage modifyvm "name" --natdnsproxy1 on