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Version 4 (Constantinos Venetsanopoulos, 10/10/2011 02:45 pm) → Version 5/133 (Constantinos Venetsanopoulos, 10/10/2011 04:15 pm)

h1. snf-image

snf-image is a Ganeti OS Provider primarly used by Synnefo.

It is written from scratch and allows Ganeti to launch instances from predefined or untrusted custom Images. The whole process of deploying an Image onto the block device (provided by Ganeti), is done in complete isolation from the physical host, enhancing robustness and security.
There are also additional hooks that allow for: user password changes, file injections, hostname customization, ssh keys cleanup. snf-image is able to deploy many major Linux distributions (Debian, Ubuntu/Kubuntu, CentOS, Fedora) and Windows 2008 R2.

snf-image requires ganeti-os-interface v20 to operate and introduces 4 parameters that supplement the procedure:

* img_id (required): the image's uid as known by the storage backend
* img_format (required): the image format (extdump and ntfsdump [dd] currently supported)
* img_passwd (required): the passwd to be injected inside the image
* img_personality (optional): files to be injected inside the image (json.dumps() of a json containing paths and base64 encoded data as proposed by the "OpenStack Compute API v1.1":http://docs.openstack.org/api/openstack-compute/1.1/content/CreateServers.html. ["more...":http://docs.openstack.org/api/openstack-compute/1.1/content/Server_Personality-d1e2543.html ])

The snf-image Ganeti OS Provider (released under a [[Licence|2-clause BSD Licence]]) can be used by any Ganeti deployment that uses KVM as the underlying hypervisor.

h2. Architecture



h2. Download

h2. Installation

Before installing snf-image be sure to have a working Ganeti installation in your cluster. The installation process should take place in *all* ganeti nodes. Here we will describe the installation in a single node. The process is identical for all nodes and should be repeated manually or automatically (e.g. with puppet).

# Download the snf-image-host debian package as described in the download section.
# Install the snf-image-host debian package:
<pre>
# dpkg -i snf-image-host_version.deb
</pre>
# If the dependencies are not met, install all the dependencies using @apt-get install@
# Download the snf-image-helper debian package as described in the download section and store it in a handy location.
# *Do NOT install the snf-image-helper debian package* in the Ganeti node (the package should be present but NOT installed in any node).
# Configuration of the packages, as described in the next section, is needed before you can use the new OS Provider.

h2. Configuration

Once you have installed snf-image-host in the Ganeti node and also snf-image-helper is present, proceed with the following configuration:

# Edit /etc/default/snf-image and set the HELPER_DIR variable to a directory in which all snf-helper related stuff are going to be stored (the directory should be able to store at least 700MB of data)
# Move the snf-image-helper debian package inside this directory and edit the HELPER_PKG variable in /etc/default/snf-image accordingly
<pre>
$ mv /path/to/handy/location/snf-image-helper_version.deb HELPER_DIR/
</pre>
# Update the helper-vm image and related data:
<pre>
$ /usr/bin/snf-image-update-helper
</pre>

h2. Features / Hooks

h2. Community & Support

* Bug-reports: snf-image-bugs@lists.grnet.gr
* Support: snf-image-support@lists.grnet.gr