Backing up before upgrading HA

Here I read that I “should Backup my installation, using the snapshot functionality Home Assistant offers”.

I’m running HA on docker; afaik, there is no snapshot functionality :roll_eyes:

So I thought to tar the config folder. That did not work because some files changed as tar read them.

Next I tried rsync:

rsync failes sometime with some files vanished before they could be transferred.

file has vanished: "/home/pi/docker/homeassistant/home-assistant_v2.db-shm"
file has vanished: "/home/pi/docker/homeassistant/home-assistant_v2.db-wal"

(I assume) Those two files are not needed to be backed up. But this throws a rsync warning and maybe there are other files/problems, when rsync runs at another time?

Is it normal, that some files in the .storage folder are owned by root?