[PVE-User] New qcow2 hard disk creates a file with full disk size.

["[SOLTECSIS] Carles Xavier Munyoz Baldó"]

Hi,
I have a two nodes Proxmox cluster with the Proxmox version 
2.2-32/3089a616 (I believe that it is the last version, am I right?)

I have seen that when I create a new qcow2 hard disk, the file created 
in the storate (a DRBD directory with ext4 file system) has the full 
size I have assigned to that hard disk.

For example, I have created a new 32GB qcow2 hard disk for a KVM vitual 
machine with ID 100. Before installing nothing into the virtual machine, 
if I execute the command ls -al I get:
[...]
-rw-r--r-- 1 root root 34365243392 Jan 23 10:01 vm-100-disk-1.qcow2
[...]

That is, the file has already the 32GB that I have setup for the new 
hard disk. Why?
Before the last Proxmox update, when I created a new qcow2 hard drive 
the new file has only a few megabytes.

But if I execute the command du -sh over the virtual machine directory I 
get:
[...]
5.5M
[...]

If I copy the file to another computer, the copy has the 32GB too and if 
I execute du -sh over the file I get the 32GB size.

I don't understant why is happening this.
Please, may someone explain it to me?

Thank you very much.
========================================
SOLTECSIS SOLUCIONES TECNOLOGICAS, S.L.
Carles Xavier Munyoz Baldó
Departamento de Tecnología
Tel./Fax: 966 446 046
cmunyoz at soltecsis.com
www.soltecsis.com
========================================

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