glance/doc/source/formats.rst
2011-05-19 10:20:54 +01:00

2.8 KiB

Disk and Container Formats

When adding an image to Glance, you are may specify what the virtual machine image's disk format and container format are.

This document explains exactly what these formats are.

Disk Format

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.

You can set your image's container format to one of the following:

  • raw

    This is an unstructured disk image format

  • vhd

    This is the VHD disk format, a common disk format used by virtual machine monitors from VMWare, Xen, Microsoft, VirtualBox, and others

  • vmdk

    Another common disk format supported by many common virtual machine monitors

  • vdi

    A disk format supported by VirtualBox virtual machine monitor and the QEMU emulator

  • iso

    An archive format for the data contents of an optical disc (e.g. CDROM).

  • qcow2

    A disk format supported by the QEMU emulator that can expand dynamically and supports Copy on Write

  • aki

    This indicates what is stored in Glance is an Amazon kernel image

  • ari

    This indicates what is stored in Glance is an Amazon ramdisk image

  • ami

    This indicates what is stored in Glance is an Amazon machine image

Container Format

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

There are two main types of container formats: OVF and Amazon's AMI. In addition, a virtual machine image may have no container format at all --basically, it's just a blob of unstructured data...

You can set your image's container format to one of the following:

  • ovf

    This is the OVF container format

  • bare

    This indicates there is no container or metadata envelope for the image

  • aki

    This indicates what is stored in Glance is an Amazon kernel image

  • ari

    This indicates what is stored in Glance is an Amazon ramdisk image

  • ami

    This indicates what is stored in Glance is an Amazon machine image