Comment 16 for bug 905095

Description of problem:

qemu-img convert cannot convert a VMDK4 format file to (eg) raw (or
anything else). It silently produces a large file that mostly
contains zero bytes, and is completely unusable.

Version-Release number of selected component (if applicable):

Tested with qemu-img 0.10.5, 0.11.0, and
git d9a50a366f2178 (2009-12-11).

How reproducible:

Always.

Steps to Reproduce:
1. Export to OVF from VMWare vSphere / ESX 4.0.0.
2. Copy the resultant disk image to a Fedora machine.
3. Check the SHA1 sums (from *.mf file) to make sure image was not
   corrupted during the copy.
4. Run:
     qemu-img convert -O raw TestLinux-disk1.vmdk TestLinux-disk1.raw
5. Try to mount / use the resulting raw file, eg. using guestfish.

Actual results:

The raw file contains mostly zeroes, see below. It contains zeroes
where there should be partition tables, superblocks etc. and so is
totally unusable.

Expected results:

A usable disk image.

Additional info:

Compare the entropy of the VMDK file with the resulting raw disk.
I would expect the entropy to be about the same, but you can see the
raw disk is mostly compressible (zeroes).

  $ ls -l TestLinux-disk1.vmdk
  -rw-rw-r-- 1 rjones rjones 887312896 2009-12-18 10:35 TestLinux-disk1.vmdk
  $ gzip -c TestLinux-disk1.vmdk | wc -c
  860846320
  $ gzip -c TestLinux-disk1.raw | wc -c
  8744715

VMWare's OVF metadata says the following about the disk format:

  <References>
    <File ovf:href="TestLinux-disk1.vmdk"
          ovf:id="file1" ovf:size="887312896" />
  </References>
  <DiskSection>
    <Info>Virtual disk information</Info>
    <Disk ovf:capacity="8"
          ovf:capacityAllocationUnits="byte * 2^30"
          ovf:diskId="vmdisk1" ovf:fileRef="file1"
          ovf:format="http://www.vmware.com/interfaces/specifications/vmdk.html#streamOptimized" />
  </DiskSection>

qemu-img 0.10.5 fails in a different way. It gives the error
message:

  qemu-img: error while reading

qemu-img >= 0.11.0 fail silently, no error message or error code.

I've tried this with several disk images exported from vSphere 4
and they have all failed to convert in the same way.

Test files (at time of writing these are STILL UPLOADING, with ETA
of 2009-12-19).

http://homes.merjis.com/~rich/TestLinux-disk1.vmdk
  SHA1: 2C81BAE89210B075ACC51DA9D025935470149D55
http://homes.merjis.com/~rich/TestLinux.ovf
  SHA1: 30831689B8C6F1B1A1FCBB728769B5F71056A580