# pve6to7 --full
# apt update
# apt upgrade
# sed -i 's/buster\/updates/bullseye-security/g;s/buster/bullseye/g' /etc/apt/sources.list
# echo "deb https://enterprise.proxmox.com/debian/pve bullseye pve-enterprise" > /etc/apt/sources.list.d/pve-enterprise.list
# echo "deb http://download.proxmox.com/debian/ceph-octopus bullseye main" > /etc/apt/sources.list.d/ceph.list
# apt update
# apt dist-upgrade
# apt remove linux-image-amd64