UPDATE: The VirtualBox installation package has been fixed. There is/was an issue with Debian's version level decision-making algorithm that is now resolved.
This is a record of what happened and if you want to take your kernel backwards, it should work for you.
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About 50 fresh-installs later, I finally cracked a VirtualBox installation nut! Yes, I may not know what I'm doing, but I got'r'done. I've historically found it helpful (for myself) to document these things so that future-me can go back and do them again the next time I blow up the OS. Here's a little venture.
Here's the TL;DR version:
- Fresh install of OMV4, but ONLY the installation. I.e. Stop where those instructions ended. Do NOT do 1.4 million updates; do not pass GO.
- Regress the Kernel back to 4.9.0-8-amd64
- Install OMV-Extras in the GUI
- At the command-line, install openmediavault
And now, the details of what I did that succeeded and I'll spare you the trials and tribulations:
- [X}: Acquire OpenMediaVault (OMV4 version 4.1.3 as of this writing). Burn it to a CD.
- GUI: Install OMV4 on your computer. Make sure you only have ONE (1) hard drive attached to your motherboard during the boot. That drive is going to get completely overwritten. Yes, it's going to wipe out the disk completely. That's the way it is. Do NOT try to install on a computer with a drive(s) that has/have any data on it because you run the risk of wiping out that drive if you make a wrong selection and you'll get no opportunity to fix that once you've said "Continue" to that step (despite what the instructions say).
- CLI: After the installation an reboot is complete (during which, it will perform some updating - that's okay), DO NOT INSTALL ANY OF THE UPDATES! Instead, update grub, to fix a Debian installation issue. It took me a long while to figure out how to not do the updates after installing OMV4, so you're really better off trusting me on this one.
Next, we're going to install the old-new kernel. I guessed at how to accomplish this using an outdated guide from 2014.
- CLI: [Optional] Correct the distracting "noneType" error in /usr/lib/python3.5/weakref.py
- GUI: Expand the Sources for apt to include both community and pre-release. [GUI: System->Update Management-> Settings} (I tried to past a picture, but this forum doesn't work that way and after the escapade with Photobucket, I'm not going that route ever again!)
- CLI: Update Apt
# apt update
# apt search linux-image
# apt-cache policy linux-image
# apt-get install linux-image-4.9.0-8-amd64
# apt-get install linux-headers-4.9.0-8-amd64
- CLI: examine /boot/grub/grub.cfg. Count the lines that start with "menuentry … " starting at zero, until you get to the line that starts as follows and write that number down (Example: 2)
- Edit the grub default file and replace the number for "GRUB_DEFAULT" with the number you wrote down from the previous step (Example: 2).
- Update grub (again) and reboot. The system (by default) should now boot into the new-old kernel
- GUI: Change the standards for picking up updates back to stable. Exclude both community and pre-release. [GUI: System->Update Management-> Settings]
- CLI: update apt again, then reboot. I'm not sure the reboot is needed here, but that's what I did, so I'm documenting it.
- CLI: install virtualbox and reboot.
That's it! After that, the vboxmanage tool works in the CLI, the VirtualBox plugin appears in the openmediavault GUI and the PHPvirtualbox works perfectly right out of the box. My "admin" password was the same as the password for the OMV GUI. This is different from a lot of the VirtualBox documentation that says the default password will be "admin," so don't freak out when it already knows "open sesame."
I apologize for the wayward manner in which the code segments got inserted into this posting. I couldn't figure out how to make them "work" in anything resembling an "intuitive" way and the "delete" and "backspace" keys were causing rampant formatting changes and the code segments to switch paragraphs, disappear, and all sorts of confusion for me. I'm not very good at all this GUI stuff.