I am following the instructions on the DietPi blog to upgrade Debian Buster to Bullseye https://dietpi.com/blog/?p=811
I am on step 2.2.3. When I click on apt update, non of the packages are due for an upgrade. Am I doing something wrong? I tried restarting the system twice.
apt update
Hit:1 https://download.docker.com/linux/raspbian bullseye InRelease
Hit:2 http://raspbian.raspberrypi.org/raspbian bullseye InRelease
Hit:3 https://downloads.plex.tv/repo/deb public InRelease
Ign:4 https://download.webmin.com/download/repository sarge InRelease
Hit:5 https://apt.sonarr.tv/debian buster InRelease
Hit:6 https://archive.raspberrypi.org/debian bullseye InRelease
Hit:7 https://download.webmin.com/download/repository sarge Release
Hit:9 https://download.mono-project.com/repo/debian raspbianbuster InRelease
Hit:8 https://packagecloud.io/golift/pkgs/ubuntu focal InRelease
Reading package lists… Done
Building dependency tree
Reading state information… Done
All packages are up to date.
I am still on Buster.
cat /etc/os-release
PRETTY_NAME=”Raspbian GNU/Linux 10 (buster)”
NAME=”Raspbian GNU/Linux”
VERSION_ID=”10″
VERSION=”10 (buster)”
VERSION_CODENAME=buster
ID=raspbian
ID_LIKE=debian
HOME_URL=”http://www.raspbian.org/”
SUPPORT_URL=”http://www.raspbian.org/RaspbianForums”
BUG_REPORT_URL=”http://www.raspbian.org/RaspbianBugs”
Since there is no package update, apt upgrade and apt full-upgrade does not migrate me to Bullseye. Any help would be appreciated.
Maybe there is a policy still active blocking your from updating your system. But I would not call it failed update as you even did not started 
Can you share following
ls -la /etc/apt/preferences.d/
ls -la /etc/apt/preferences.d/
total 12
drwxr-xr-x 2 root root 4096 Mar 1 2021 .
drwxr-xr-x 7 root root 4096 Sep 15 17:37 ..
-rw-r--r-- 1 root root 145 May 25 2020 pivpn-limit-bullseye
ah you have PiVPN installed. As far as I can see PiVPN installer is setting the preference. Can you check if a source list is existing as well
ls -la /etc/apt/sources.list.d/
root@DietPi-Pi4:~# ls -la /etc/apt/sources.list.d/
total 52
drwxr-xr-x 2 root root 4096 Sep 15 17:38 .
drwxr-xr-x 7 root root 4096 Sep 15 17:37 ..
-rw-r--r-- 1 root root 79 Sep 15 17:36 debian-backports.list
-rw-r--r-- 1 root root 62 Sep 15 17:35 docker.list
-rw-r--r-- 1 root root 58 Sep 15 17:08 golift.list
-rw-r--r-- 1 root root 71 Sep 15 17:10 mono-xamarin.list
-rw-r--r-- 1 root root 59 Sep 15 17:38 pivpn-bullseye.list
-rw-r--r-- 1 root root 52 Sep 15 17:08 plexmediaserver.list
-rw-r--r-- 1 root root 226 May 5 2020 plexmediaserver.list.dpkg-dist
-rw-r--r-- 1 root root 58 Sep 15 17:08 raspi.list
-rw-r--r-- 1 root root 46 Sep 15 17:10 sonarr.list
-rw-r--r-- 1 root root 42 Sep 15 17:08 vscode.list
-rw-r--r-- 1 root root 67 Sep 15 17:08 webmin.list
PiVPN sources as well as preferences list would need to be deleted.
rm /etc/apt/sources.list.d/pivpn-bullseye.list
rm /etc/apt/preferences.d/pivpn-limit-bullseye
apt update
Thanks a lot. This worked 
our blog has been updated to reflect PiVPN being installed.
ADMIN EDIT: I moved the curl issue into the related topic to have all on one place https://dietpi.com/forum/t/curl-error-while-loading-shared-libraries/5674/1
Joulinar As discussed, I tried upgrading to bullseye and I got the following error with apt full-upgrade
apt full-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Error!
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
libc6-dev : Breaks: libgcc-8-dev (< 8.4.0-2~) but 8.3.0-6+rpi1 is to be installed
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
Any help? The curl issue is now resolved
does FroFTP completed now? Because you stated there are some issues with?
could you run apt update && apt upgrade and poste the output
I uninstalled Proftpd before upgrading to Bullseye. So didn’t face that issue.
This did the trick and solved the issue.
apt install gcc-8-base
Doing a full upgrade now. Will update you if I come across any issues. Fingers crossed 
yes there is a setting in ProFTP config file that would need to be changes before. Basically not a big deal 
sed -i '/IdentLookups/c\<IfModule mod_ident.c>\nIdentLookups off\n</IfModule>' /etc/proftpd/proftpd.conf
On new installations we already have that implemented with DietPi 7.5. I guess the blog would need to be extended by this as well.
Successfully migrated to Bullyseye. Facing issue with lighttpd
/usr/sbin/lighttpd -tt -f /etc/lighttpd/lighttpd.conf
2021-09-16 17:12:52: plugin.c.195) dlopen() failed for: /usr/lib/lighttpd/mod_openssl.so /usr/lib/lighttpd/mod_openssl.so: cannot open shared object file: No such file or directory
2021-09-16 17:12:52: server.c.1238) loading plugins finally failed
It has to do with SSL configured. I don’t seem to have this module “mod_openssl.so”. Has something changed in Bullseye?
this worked
apt install lighttpd-mod-openssl