VM image introspection

Image formats

RAW – Unstructured disk image format.
QCOW2 – Disk format supported by QEMU emulator.
ISO – Sector-by-sector copy of the data on a disk, stored in a binary file.
AKI – Indicates an Amazon Kernel Image.
AMI – Indicates an Amazon Machine Image.
ARI – Indicates an Amazon RAMDisk Image.
VDI – Disk format supported by VirtualBox virtual machine monitor and the QEMU emulator.
VHD – Common disk format used by virtual machine monitors from VMWare, VirtualBox, and others.
VMDK – Disk format supported by many common virtual machine monitors.

Every image format comes with a set a metadata embedded inside the image itself.

$ head -20 image.vmdk

# Disk DescriptorFile

# Extent description
RDONLY 209714 SPARSE “generated-stream.vmdk”

# The Disk Data Base

ddb.adapterType = “buslogic”
ddb.geometry.cylinders = “102”
ddb.geometry.heads = “64”
ddb.geometry.sectors = “32”
ddb.virtualHWVersion = “4”


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