Quick vSphere OVF/OVA Hack

Posted by Kenneth Ristau on February 7, 2013
Posted in: Technology, Virualization. Tagged: , , , .

Found myself in a predicament just the other day. I had spent several hours building out template VMs for a few servers, installing vmtools, applying all the latest updates, running sysprep, etc. At the end of that effort, I exported them to .ova files and removed the original VMs. Then I decided I might want to test these .ova exports to make sure they work. Well, guess what? I found myself with broken .ova files that would not import.

The error message, “OVF Deployment Failed: File ds:///vmfs/volumes/uuid/_deviceImage-0.iso was not found” led me to VMware KB article 2034422. The resolution, of course, required use of the original source VMs which I had over zealously deleted earlier. Thankfully, the article gave enough detail about the issue that I was able to work up the following little hack to repair my damaged .ova files:

  1. I extracted the contents of the .ova files using tar. This works because .ova files are just uncompressed tar archives. You could also use 7zip on Windows.
  2. Inside, there was one .mf or manifest file, one .ovf file, and one .vmdk. There would be more .vmdk files if I had more drives associated with the VMs.
  3. I edited the .ovf file to change the text “vmware.cdrom.iso” to “vmware.cdrom.remotepassthrough”. The reason for the failure was that the import process was trying to mount a non-existent vmware tools iso image.
  4. Once edited, the SHA1 sum of the .ovf file had changed, causing it to not match the sum contained in the manifest. I generated a new SHA1 sum and replaced the original in the .mf manifest file.
  5. Finally, I re-archived the files with tar, making sure to change the extension on the end back to .ova. The tricky bit to this is to make sure you add the files to the archive in the correct order. The .ovf has to be the first file in the archive. Use tar cvf archive.ova vm.ovf to create, then tar uvf archive.ova *.mv *.vmdk to append the rest of the files. Note that I couldn’t get 7zip to archive these in order. I had to use GNU tar from an Ubuntu VM.

I was then able to successfully import the .ova files back into my vSphere environment.