"Error on do-release-upgrade -d 18.04 to 20.04 (mixed destop & server)"

[Eric Cosnard]

**** cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=18.04
DISTRIB_CODENAME=bionic
DISTRIB_DESCRIPTION="Ubuntu 18.04.4 LTS"
**** screenfetch
                          ./+o+- ****@BazUbu
                  yyyyy- -yyyyyy+ OS: Ubuntu 18.04 bionic
               ://+//////-yyyyyyo Kernel: x86_64 Linux 4.15.0-111-generic
           .++ .:/++++++/-.+sss/` Uptime: 1h 54m
         .:++o: /++++++++/:--:/- Packages: 4601
        o:+o+:++.`..```.-/oo+++++/ Shell: bash 4.4.20
       .:+o:+o/. `+sssoo+/ Resolution: 3360x1080
  .++/+:+oo+o:` /sssooo. DE: GNOME
 /+++//+:`oo+o /::--:. WM: GNOME Shell
 \+/+o+++`o++o ++////. WM Theme: Radiance
  .++.o+++oo+:` /dddhhh. GTK Theme: Ambiance [GTK2/3]
       .+.o+oo:. `oddhhhh+ Icon Theme: ubuntu-mono-light
        \+.++o+o``-````.:ohdhhhhh+ Font: Ubuntu 11
         `:o+++ `ohhhhhhhhyo++os: CPU: Intel Core i7-2600 @ 8x 3.8GHz
           .o:`.syhhhhhhh/.oo++o` GPU: Mesa DRI Intel(R) HD Graphics 2000 (SNB GT1)
               /osyyyyyyo++ooo+++/ RAM: 3762MiB / 15976MiB
                   ````` +oo+++o\:
                          `oo++.
I have certainly problem of dependencies, packages installed out of ubuntu... But what to do???
File apt.log shows many things but I don't see the problem. This computer runs first on 12.04 and I migrate up to 18.04 without too much problems (desktop, apache, virtualbox...). How to know which packages are not supported?

Best regards

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.37
ProcVersionSignature: Ubuntu 4.15.0-111.112-generic 4.15.18
Uname: Linux 4.15.0-111-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.15
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Mon Jul 13 21:08:14 2020
InstallationDate: Installed on 2012-07-21 (2914 days ago)
InstallationMedia: Ubuntu 12.04 "Precise" - Build amd64 LIVE Binary 20120425-15:28
PackageArchitecture: all
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to bionic on 2020-07-13 (0 days ago)
VarLogDistupgradeAptclonesystemstate.tar.gz: Error: command ['pkexec', 'cat', '/var/log/dist-upgrade/apt-clone_system_state.tar.gz'] failed with exit code 127: Error checking for authorization org.freedesktop.policykit.exec: GDBus.Error:org.freedesktop.DBus.Error.NoReply: Message recipient disconnected from message bus without replying

[Brian Murray (brian-murray)]

According to VarLogDistupgradeMainlog.txt you don't have a desktop meta package installed. Please try installing ubuntu-desktop and upgrading again.

2020-07-13 21:07:16,923 DEBUG need_server_mode(): can not find a desktop meta package or key deps, running in server mode

[Launchpad Janitor (janitor)]

[Expired for ubuntu-release-upgrader (Ubuntu) because there has been no activity for 60 days.]