Both vdi and qcow images are compressed, so a a 10 Gb .vid or .qcow will take less space on your hard drive. Conversion, however, requires you to first convert the .vdi to a raw image, which will require the full 10 Gb, so plan accordingly.

Assume your VirtualBox image is called “ubuntu.vdi”

Step 1. Convert the VB disk vdi image to a raw image format.

#VBoxManage clonehd --format RAW ubuntu.vdi ubuntu.img

Note: The ubunut.img is a raw disk image, it will be quite large (as many GB as your virtual drive is, see above).

Step 2 : convert the raw image to a qcow

#qemu-img convert -f raw ubuntu.img -O qcow2 ubuntu.qcow

Upload the ubuntu.qcow to web/ftp server and Import it as appliance from VxDataCenter