per SSH anmelden
screen installieren und starten (apt install screen, screen, STRG+A d = detach, screen -ls = auflisten, screen -r = attach)
proxmox-backup-manager versions = Version checken
UI -> Datastore (backup) -> Options -> Maintenance aktivieren
sed -i ’s/bullseye/bookworm/g‘ /etc/apt/sources.list = Repositories aktualisieren (etc/apt/Sources.list prüfen)
apt update
apt dist-upgrade (Y to all)
systemctl reboot
proxmox-backup-manager versions = Version checken
UI -> Datastore (backup) -> Options -> Maintenance deaktivieren