cannot valid stream-optimized vmdk image

[zhou zhong]

My vmdk image file cannot be validated, and raise "Unsupported VMDK footer". It seems that every stream-optimized VMDK image has a footer, why verify its existence?

Traceback (most recent call last):
  File "/Users/mizar/test/format_inspector.py", line 874, in <module>
    get_inspector('vmdk').from_file('/Users/mizar/Downloads/zztest-thin-1.vmdk')
  File "/Users/mizar/test/format_inspector.py", line 225, in from_file
    inspector.eat_chunk(chunk)
  File "/Users/mizar/test/format_inspector.py", line 142, in eat_chunk
    self.post_process()
  File "/Users/mizar/test/format_inspector.py", line 675, in post_process
    raise ImageFormatError('Unsupported VMDK footer')
ImageFormatError: Unsupported VMDK footer

()[root@nova-maintenance-b7f767857-8t2r2 /]# qemu-img info /opt/zztest-centos7-1.vmdk
image: /opt/zztest-centos7-manu-virtio-1.vmdk
file format: vmdk
virtual size: 16G (17179869184 bytes)
disk size: 629M
cluster_size: 65536
Format specific information:
    cid: 2728887714
    parent cid: 4294967295
    create type: streamOptimized
    extents:
        [0]:
            compressed: true
            virtual size: 17179869184
            filename: /opt/zztest-centos7-1.vmdk
            cluster size: 65536
            format:

[OpenStack Infra (hudson-openstack)]

Related fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/glance/+/924298

[Dan Smith (danms)]

It is not true that all streamOptimized VMDKs have a footer. Files created with qemu-img in that subformat do not have one. If you can provide an example VMDK that does, I can take a look at it, but the VMDK spec is very light on details about how that might even work and whether or not there can be another descriptor block beyond it.

[Dan Smith (danms)]

I added nova and cinder to this for visibility. I have a patch up to add footer support to the oslo version, but it's non-trivial and depends on some of the changes I've made since the version imported by the other projects.

For nova, I'm definitely suggesting that we not take action on this until we can switch to the oslo version, and because the code is doing exactly what we want, which is rejecting VMDKs with a sparse footer that we can't validate. This doesn't affect VMDKs created by qemu, and I'm not sure all the scenarios under which VMDKs created from vmware have this set. Either way, a 1:1 `qemu-img convert` of the affected files will un-footer it and make it usable. So, working as designed but lacking support for an edge case and with a valid workaround tells me this is low priority and more feature than bug.

[Walt Boring (walter-boring)]

Do you have a copy of this vmdk file?

[Dan Smith (danms)]

I've scripted creating a vmdk with a footer and am working on getting all these sample images available statically. But you can clone this:

https://review.opendev.org/c/openstack/os-test-images/+/925114

Run tox, and get the images/vmdk-sparse-with-footer.vmdk file to test with if you need.

[zhou zhong (zhouzhongg)]

Hi Walt, you can find the image at https://we.tl/t-o1wkLvdVsl