[Solved] Debian 9 Stretch to Debian 10 Buster upgrade catastrophe
 

Just a story/reference for anyone in failure and about to blow their lids. (This was practically an 8 hour day for me)

My machine had prior been upgraded in-place from Deb 8 to Deb 9 when released (flawlessly).

On Tue Jul 9, I set my sources.list to stable/buster only. upgraded to Deb 10 in-place. Disaster.

Firstly, i had to uninstall a bunch of packages to get many of the updates, not a problem, just a hassle.

When all was done, it would not boot -- kernel panic reporting something about mount/unknown block device (or similar; i did not save the exact text). I found tons of resources, but the one that worked for me is: https://www.linux.com/learn/how-resc...g-grub-2-linux

One of the biggest issues was that Debian 10 uninstalled prior kernels from grub and I could not install the older kernels because they were not available from Deb 10. I was LUCKY that one older kernel was still in the /boot/ folder, even though it was not in the grub config.

Once I got the older kernel loaded and made the referenced link's actions permanent, it would only boot into emergency mode. This root issue was that plymouth repeatedly failed to install the kernel correctly during the apt/aptitude configuration. My solution was to remove plymouth and install dracut. These are the tools that create the initial ramdisk images. "apt upgrade" was able to succeed using dracut.

Now my Debian 10 reboots were successfull.... but wait there's more!

My Pulse Audio had zero sound and only a dummy-sink.

2.3 million internet resources failed to help me. I referenced my recently clean installed xubuntu machine and noticed it had very minimal alsa packages. so i matched such on my Debian by purging all alsa packages except alsa-base and alsa-utils. This involved removing some applications that thankfully i no longer used. I also preformed an "aptitude --reinstall" of pulseaudio, but it still failed. Finally, I had to create /etc/alsa/conf.d/99-pulse.conf with the contents from my Xubuntu machine which worked in full. (https://hatebin.com/pebtmuiyqr )

My XFCE panel had no indicator icons for about half of my running programs. In addition to my already existing "Notification Area" plugin, I had to add had to add "Indicator Plugin" to my top panel.

Maybe none of you will have or have had these problems, but hopefully this may help someone in need.

Plymouth plays no part in the creation of ramdisk images. It is commonly implicated in boot failures and black screen trouble, for which its removal is a common cure or workaround.

thanks man, probably a misunderstanding on my part. the apt/aptitude upgrade did report plymouth failure at the kernel apt --configure part specifically, sooo... maybe just a grub/theme issue for it. No matter, as you say, removal solved.