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Overview
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^^^^^^^^
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snf-image-creator is a simple command-line tool for creating OS images. The
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original media, the image is created from, can be:

 * a block device, representing a hard disk
 * a disk image file, representing a hard disk (supports all image file formats
   supported by QEMU)
 * the host system itself
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Snapshotting
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============
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snf-image-creator works on snapshots. Any changes made by the program do not
affect the original media.
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Image Preparation
=================
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During the image creation, a number of system preparation operations are
applied on the media snapshot. Some of those are OS specific. snf-image-creator
will use heuristics to detect the OS and determine which operations to apply.
Those operations will:
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 * Shrink the image
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 * Clear out sensitive user data (passwords, ssh keys, history files, etc.)
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 * Prepare the guest OS for being deployed on a virtual environment (change
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   device names, remove persistent net rules, install VirtIO drivers, etc.)
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Creation
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========
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The program can either dump the image file locally or use
`./kamaki <https://code.grnet.gr/projects/kamaki>`_ to directly upload and
register it on a `Synnefo <https://code.grnet.gr/projects/synnefo>`_
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deployment as private or public image.
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Image Format
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============
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The extracted images are in diskdump format, which is a raw dump of a disk
device (or file). This is the recommended format for
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`snf-image <https://code.grnet.gr/projects/snf-image>`_, the Ganeti OS
Definition used by `Synnefo <https://code.grnet.gr/projects/synnefo>`_.