root@pve:~# cat /etc/apt/sources.list
deb http://ftp.de.debian.org/debian bullseye main contrib

deb http://ftp.de.debian.org/debian bullseye-updates main contrib

# security updates
deb http://security.debian.org bullseye-security main contrib
deb http://download.proxmox.com/debian/pve bullseye pve-no-subscription