[et-mgmt-tools] Cobbler Image Cloning Patches
bkearney at redhat.com
Wed Nov 12 13:14:26 UTC 2008
Michael asked that I post a summary about the some cobbler patches from
yesterday which provide a virt-image driver to koan. Here is the quick
summary which I sent to the cobbler list:
The patches allow the user to import a pre-configured image (virtual
appliance) into cobbler, and to provision it via koan. Outside of koan,
the process would be something akin to:
I) Create the appliance from a kickstart file using he appliance-creator
 tool. This creates a raw image file and a virt-image xml  file
which is the metadata about the appliance.
II) Locate a VMWare appliance and convert it the virt-image file using
the virt-convert tooling. Again, this gives you a raw disk and
appliance metadata in the form of an XML File.
III) Install the appliance into your hypervisor of choice using
These patches allow the metadata in the appliance xml file (output of I
or II) to be stored within cobbler. The mapping for this information is
below. Koan then uses this data on the client machine to copy the image
file and to install it using virt-image libraries. In effect, this is
step III above.
The process for this is then:
A) Assume you have an image which is located on network accessable storage
B) Add the image to cobbler using "cobbler add image -name FOO ..... "
or one of the APIs. The image-type should be virt-clone.
C) Using koan, deploy the image using a command such as "koan --server
localhost --image base --virt --virt-path /tmp"
D) During deployment, koan will create one NIC based on the new
network_count attribute. These are filled either with bridges defined in
the image or with the default network connection.
The image type of "virt-clone" will tell koan to use the virt-image
driver. The --virt-path argument says where to copy the image to
locally.. since this is a clone. The --virt-type argument can be used,
or virt-image will detect your hypervisor.
I would like to see a tool which does all of step B based off of the
existing xml file, but that is not written yet. I also noticed I need to
add network_count to the cli add function.
Any comments or concerns are appreciated.
Mapping between Cobbler and virt-image xml
Cobbler :: Virt-Image-XML :: Notes
CobblerImage.name :: image.name :: Overridden at command line
CobblerImage.arch :: None :: Need to translate this since virt-image
seems to use i686 not i386
CobblerImage.file :: image.domain.boot.drive | image.storage.disk at file
:: What is lost is the ability to denote boot drives
CobblerImage.parent :: None :: Not needed as this is internal cobbler logic
CobblerImage.depth :: None :: Not needed as this is internal cobbler logic
CobblerImage.owners :: None :: Not needed as this is internal cobbler logic
CobblerImage.virt_ram :: image.domain.devices.memory ::
CobblerImage.virt_file_size :: None ::
CobblerImage.virt_path :: None :: Used to denote where to copy the image
on the local filesystem
CobblerImage.virt_cpus :: image.domain.devices.vcpu ::
CobblerImae.network_count :: image.domain.networks ::
CobblerImage.virt_type :: image.domain.boot at type |
image.domain.boot.os.loader at dev :: See Issue 2
CobblerImage.virt_bridge :: :: Creates one nic on the guest for each entry
CobblerImage.xml_file :: None :: No need to store the file, virt-image
is called directlry
CobblerImage.image_type :: virt-clone :: May need to break this down
once we resolve the issues below
CobblerImage.breed, :: None ::
CobblerImage.os_version, :: None ::
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