[virt-tools-list] dynamically allocated disks

LK cesto at email.it
Tue Jan 10 16:34:02 UTC 2017

Just a last question: if I try to create a qcow2 disk that is greater 
that the available actual available size, virt-manager gets an error.

Is there a way to create a sparse disk greater than the available size?



On 10/01/2017 13:34, Pavel Hrdina wrote:
> On Tue, Jan 10, 2017 at 12:53:55PM +0100, LK wrote:
>> Hi,
>> I thought that qcow2 would be a sparse disk format, but when I create a
>> new disk using virt-manager (Ubuntu 16.10, virt-manager 1.3.2), the size
>> of the new disk is exactly the same size I chose at creation time (as
>> the disk would be completely full).
>> Ho can I create a dynamically allocated disk using virt-manager?
> Hi,
> they are probably allocated as sparse files.  You can try to run:
>    qemu-img info /path/to/file.qcow2
> and the output should contain those two lines:
>    virtual size: 20G (21474836480 bytes)
>    disk size: 3.3M
> or you can use this command:
>    ls -lsh
> and the output should be something like this:
>    3.4M -rw------- 1 root root  21G Jan 10 13:28 test-size.qcow2
> where the first column is the sparse size.
> Pavel

More information about the virt-tools-list mailing list