by CwF » 2019-06-18 12:35
#2
Simple, I did say to image that basic install. For practice, take it to a full system, then blow it up...Remove things until you're dumped to a prompt...try to clean it as best you can, then compare it to that clean base image. This will show you the difference between remove and purge, will show you how much is actually left in system directories. This is the basis for me harping on people to learn to fix rather than reinstall, because the learning exercises are straight forward. Yes you can strip a frankendebian down to nothing and start over, and yes it's often faster than a reinstall.
I use one of four images, all were originally Jessie, all now >80% Buster. I've broken them many times, blank cursor, grub-rescue, lots of examples. I haven't reinstalled ever. Things do need broken down into steps, DO NOT rely on sweeping commands to do it magically in one step. APT is really smart, but not that smart. As long as it boots and gets to something, even an empty blinking cursor, it can be fixed. I don't know if it's cheating, but having the image capable of running as a vm, or at least mountable on another machine is sometimes necessary. All four of my images (except i386) run on every machine I use. When I upgrade an image it is usually in a vm, but is always run through on bare metal before it becomes the current. I consider them living images, they will someday be bullseye. I don't allow any auto updates, these do not 'ROLL', they are pushed, pulled, towed when I feel the need and have the time.
On lightDM it seems some video cards do things different. It's best not to have a user xorg.conf if possible. LightDM does jump from screen to screen following the mouse when things are working right, you do have to move the mouse. I run multiple cards each with multiple monitors each without an xorg file, and I've seen it work differently depending on specifics.
For images I use qemu-utils. On all images, any image can be used to re-image any image....