root@debian:/etc/apt# uname -r
4.19.0-6-amd64
root@debian:/etc/apt#
# deb cdrom:[Debian GNU/Linux 10.2.0 _Buster_ - Official amd64 NETINST 20191116-09:56]/ buster main
#deb cdrom:[Debian GNU/Linux 10.2.0 _Buster_ - Official amd64 NETINST 20191116-09:56]/ buster main
deb http://debian.volia.net/debian/ bullseye main non-free contrib
deb-src http://debian.volia.net/debian/ bullseye main non-free contrib
deb http://security.debian.org/ bullseye/updates main contrib non-free
deb-src http://security.debian.org/ bullseye/updates main contrib non-free
# buster-updates, previously known as 'volatile'
#deb http://debian.volia.net/debian/ buster-updates main
#deb-src http://debian.volia.net/debian/ buster-updates main
# This system was installed using small removable media
# (e.g. netinst, live or single CD). The matching "deb cdrom"
# entries were disabled at the end of the installation process.
# For information about how to configure apt package sources,
# see the sources.list(5) manual.
root@debian:/etc/apt# apt update
Hit:1 http://debian.volia.net/debian bullseye InRelease
Ign:2 http://security.debian.org bullseye/updates InRelease
Err:3 http://security.debian.org bullseye/updates Release
404 Not Found [IP: 151.101.112.204 80]
Reading package lists... Done
E: The repository 'http://security.debian.org bullseye/updates Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
root@debian:/etc/apt#