openstack team mailing list archive

[Lorin Hochstein <lorin@xxxxxxxxxxxxxxxxxx>]

On Mar 29, 2012, at 12:40 PM, Daniel P. Berrange wrote:

> On Wed, Mar 28, 2012 at 04:41:28PM -0400, Lorin Hochstein wrote:
>> All:
>> 
>> Given that I have a qcow2 image from somewhere (e.g., downloaded
>> it from a uec-images.ubuntu.com, created one from a raw image using
>> qemu-img) that i want to add to glance:
>> 
>> 1. How can I tell whether it's an "ovf" or "bare" container format?
> 
> You are mixing up terminology here. Disk image formats are things like
> raw, qcow2, vmdk, etc.
> 
> OVF refers to the format of a metadata file provided alongside the
> disk image, which describes various requirements for running the
> image.
> 
> The two are not tied together at all, merely complementary to
> each other.
> 

Thanks, that clears things up. I was confused by this language, which sounded to me like the metadata was embedded in the disk image file:

http://glance.openstack.org/formats.html

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

In addition, the docs have examples like this, which clearly aren't meaningful:
http://glance.openstack.org/glance.html#important-information-about-uploading-images


$> glance add name="My Image" is_public=true \
     container_format=ovf disk_format=raw < /tmp/images/myimage.iso

I'll propose a change to the docs for that.

> 
>> Whenever I add a qcow2 image to glance, I always choose "ovf",
>> even though it's probably "bare", because I saw an example
>> somewhere, and it just works, so I keep doing it. But I don't
>> know how to inspect a binary file to determine what its container
>> is (if "file image.qcow2" says it's a QEMU QCOW2 Image (v2), does
>> that mean it's "bare"?). In particular, why does the user need to
>> specify this information?
> 
> If you simply have a single  someimage.qcow2 file, then you simply
> have a disk image. Thus there is no OVF metadata involved at all.
> 
> eg, this is the (qcow2) disk image:
> 
>  http://uec-images.ubuntu.com/precise/current/precise-server-cloudimg-amd64-disk1.img
> 
> While this is an OVF metadata file that optionally accompanies the disk image
> 
>  http://uec-images.ubuntu.com/precise/current/precise-server-cloudimg-amd64.ovf
> 

Gotcha.


It's not clear to me how you would specify the OVF metadata file when adding an image file to glance.


Take care,

Lorin
--
Lorin Hochstein
Lead Architect - Cloud Services
Nimbis Services, Inc.
www.nimbisservices.com