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Disk and container formats for images
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When you add an image to the Image service, you can specify
its disk and container formats.

Disk formats
~~~~~~~~~~~~

The disk format of a virtual machine image is the format of the
underlying disk image.
Virtual appliance vendors have different formats for laying out
the information contained in a virtual machine disk image.

Set the disk format for your image to one of the following values:

aki
 An Amazon kernel image.
ami
 An Amazon machine image.
ari
 An Amazon ramdisk image.
iso
 An archive format for the data contents of an optical disc,
 such as CD-ROM.
qcow2
 Supported by the QEMU emulator that can expand dynamically
 and supports Copy on Write.
raw
 An unstructured disk image format; if you have a file
 without an extension it is possibly a raw format.
vdi
 Supported by VirtualBox virtual machine monitor and the QEMU emulator.
vhd
 The VHD disk format, a common disk format used by virtual
 machine monitors from VMware, Xen, Microsoft, VirtualBox, and others.
vmdk
 Common disk format supported by many common virtual machine monitors.

Container formats
~~~~~~~~~~~~~~~~~

The container format indicates whether the virtual machine image is in
a file format that also contains metadata about the actual virtual machine.

.. note::

   The Image service and other OpenStack projects do not currently
   support the container format. It is safe to specify ``bare`` as
   the container format if you are unsure.

You can set the container format for your image to one of the following
values:

aki
 An Amazon kernel image.
ami
 An Amazon machine image.
ari
 An Amazon ramdisk image.
bare
 The image does not have a container or metadata envelope.
docker
 A docker container format.
ovf
 The OVF container format.