Bug 1121889

Summary:	qemu-img refuse to create 0-sized vmdk images
Product:	Red Hat Enterprise Linux 6	Reporter:	Sibiao Luo <sluo>
Component:	qemu-kvm	Assignee:	Virtualization Maintenance <virt-maint>
Status:	CLOSED WONTFIX	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	low	Docs Contact:
Priority:	low
Version:	6.5	CC:	acathrow, bsarathy, chayang, famz, juzhang, kwolf, michen, mkenneth, pbonzini, qzhang, virt-maint, xfu
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:
Clones:	1121891 (view as bug list)		Environment:
Last Closed:	2014-07-22 07:49:50 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	1121891

Description Sibiao Luo 2014-07-22 06:46:39 UTC

Description of problem:
qemu-img refused to create 0-sized vmdk image, but qcow2 format will not be refused. I don't know whether VMware tools can allow us to create 0-sized image and operate on them.

Version-Release number of selected component (if applicable):
# uname -r && rpm -q qemu-kvm-rhev
2.6.32-492.el6.x86_64
qemu-kvm-rhev-0.12.1.2-2.430.el6.x86_64

How reproducible:
100%

Steps to Reproduce:
1.use qemu-img to create 0-sized vmdk image.
# qemu-img create -f vmdk test.vmdk 0k
2.
3.

Actual results:
# qemu-img create -f vmdk test.vmdk 0k
Formatting 'test.vmdk', fmt=vmdk size=0 compat6=off zeroed_grain=off 
test.vmdk: error while creating vmdk: No such file or directory

Expected results:
It should work well if use qemu-img to create 0-sized vmdk image.

Additional info:
# qemu-img create -f qcow2 test.qcow2 0k
Formatting 'test.qcow2', fmt=qcow2 size=0 encryption=off cluster_size=65536 
# qemu-img info test.qcow2 
image: test.qcow2
file format: qcow2
virtual size: 0 (0 bytes)
disk size: 132K
cluster_size: 65536

Comment 1 Sibiao Luo 2014-07-22 06:55:19 UTC

(In reply to Sibiao Luo from comment #0)
> I don't know whether VMware tools can allow us to create 0-sized
> image and operate on them.
> 
I use the VMware vSphere Client(Version 5.1.0) to create new virtual disk with 0-sized specified, it will give a warning prompt message "The disk capacity entered was not a properly formed number or was out of range. It has been replaced with the nearest acceptable value." and replace into 1MB for recommending.

Best Regards,
sluo

Comment 2 Fam Zheng 2014-07-22 07:49:50 UTC

(In reply to Sibiao Luo from comment #1)
> (In reply to Sibiao Luo from comment #0)
> > I don't know whether VMware tools can allow us to create 0-sized
> > image and operate on them.
> > 
> I use the VMware vSphere Client(Version 5.1.0) to create new virtual disk
> with 0-sized specified, it will give a warning prompt message "The disk
> capacity entered was not a properly formed number or was out of range. It
> has been replaced with the nearest acceptable value." and replace into 1MB
> for recommending.
> 

Yes, we conform to the behavior of VMware tools. Intended.

Fam