Wiki.Cyli.Org

Things to do if you need to re-build a Debian based machine, assuming the older one can still be logged into.

# As root, on the old machine, get there how you will...
apt install debsums
mount <BackupsLocation> /mnt
# Get a list of changed files in /etc
find /etc -type f | grep -vFf <(debsums -e | grep OK$ | sed 's/[[:space:]]*OK$//') > /mnt/FileList.txt
# Copy those files over
rsync -avz --files-from=/mnt/FileList.txt /mnt/

On the new machine, install the OS, avoid updates during install, then;

sudo apt install etckeeper git tig
sudo apt update
sudo apt upgrade
sudo shutdown -r now

And then, after the reboot, install your favorite applications, mount the backup from the first block of code and merge with the local install.