[fedora-virt] qcow2, raw, COW

[Cole Robinson]

On 07/20/2014 09:38 PM, shyu wrote:
> 
> On 07/21/2014 01:42 AM, Gene Czarcinski wrote:
>> On 07/20/2014 11:25 AM, Jorge Fábregas wrote:
>>> On 07/20/2014 11:09 AM, Gene Czarcinski wrote:
>>>> 2. I want the default disk image format to be raw rather than qcow2.
>>> Hi Gene,
>>>
>>> There's an option in virt-manager for that.  Go to Edit --> Preferences
>>> :  you'll see it on the "New VM' tab.
>>>
>>>
>> Thank you.
>>
>> I must have known this at one time because the system where it was working
>> had that set.
>>
>> However, that does not explain why virtsh pool-edit default ignored the
>> addition of <format type='raw'>
>>
> Because directory pool does not use the pool format type element.
> You can refer to http://libvirt.org/storage.html
> 

Some pools do have a <format> element FWIW

However, in this case, Gene sounds like he's talking about a volume <format>
element, since only volumes will ever report qcow2/raw.

Gene, the reason that pool-edit/vol-edit won't work for changing a volume's
format from raw to qcow2 is that it's a read only XML value, just reporting
what the format of the referenced disk image is. If you want to change the
disk image format, you will have to manually use 'qemu-img convert', then do
'sudo virsh pool-refresh <poolname>' of the parent pool and it should pick up
the change.

- Cole