Ubuntu – How to mount a virtual hard disk

mountvirtualization

Is it possible to mount a virtual hard disk (VHD, HDD, VDI, VMDK) on Ubuntu? How can this be done?

Best Answer

According to this wikibooks article:

Linux and other Unix-like hosts can mount images created with the raw format type using a loopback device. From a root login (or using sudo), mount a loopback with an offset of 32,256.

mount -o loop,offset=32256 /path/to/image.img /mnt/mountpoint

For other types of qemu images, you can use qemu-nbd

modprobe nbd max_part=16
qemu-nbd -c /dev/nbd0 image.qcow2
partprobe /dev/nbd0
mount /dev/nbd0p1 /mnt/image

Plus, usually, you can convert image from one format to another.

raw - (default) the raw format is a plain binary image of the disc 
       image, and is very portable. 
       On filesystems that support sparse files, 
       images in this format only use the 
       space actually used by the data recorded in them.
cloop -     Compressed Loop format, mainly used for reading Knoppix 
       and similar live CD image formats
cow - copy-on-write format, supported for historical reasons only and
       not available to QEMU on Windows
qcow - the old QEMU copy-on-write format, supported for 
       historical reasons and superseded by qcow2
qcow2 - QEMU copy-on-write format with a range of special features, 
       including the ability to take multiple snapshots, smaller 
       images on filesystems that don't support sparse files, 
       optional AES encryption, and optional zlib compression
vmdk - VMware 3 & 4, or 6 image format, for exchanging images 
       with that product
vdi - VirtualBox 1.1 compatible image format, for exchanging 
       images with VirtualBox.

I found this solution for (VirtualBox) .VDI when I searched, on this website:

modprobe nbd max_part=16
qemu-nbd -c /dev/nbd0 /path/to/some.vdi
mount -o loop /dev/nbd0p1 /mnt
# do stuff
umount /mnt
qemu-nbd -d /dev/nbd0
rmmod nbd

The same as "Qemu's way" commands. No borders!