How did I upgrade Debian from 10 (Buster) to 12 (Bookworm)?

Step 1

Check the version installed:

lsb_release -a


Step 2

apt-get update

Step 3

apt-get dist-upgrade

Step 4

Step 5

How did I fix «The /var/lib/dkms/aufs/4.19+20190211/6.1.0-10-amd64/x86_64/dkms.conf for module aufs includes a BUILD_EXCLUSIVE directive which does not match this kernel/arch/config»?

Step 6

Re-fix the Sury UCFR errors:

Step 7

How did I fix «UnsupportedBackendScheme: scheme not supported in url: s3+http://<…>» for Duplicity / Backupninja?