[Bug 1924951] [NEW] Cannot upgrade from 18.04 to 20.04 "An unresolvable problem occured while calculating the upgrade."

[Jochen Ehnes]

Public bug reported:

Description:	Ubuntu 18.04.5 LTS
Release:	18.04

I clicked the button to upgrade the system in the dialogue box that
popped up telling me that there is a new version of the OS I can upgrade
to.

After the Distribution upgrade was running for a short while, it showed
the following error message:

Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade.

 If none of this applies, then please report this bug using the command
'ubuntu-bug ubuntu-release-upgrader-core' in a terminal. If you want to
investigate this yourself the log files in '/var/log/dist-upgrade' will
contain details about the upgrade. Specifically, look at 'main.log' and
'apt.log'.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubuntu-release-upgrader-core 1:18.04.42
ProcVersionSignature: Ubuntu 5.4.0-62.70~18.04.1-generic 5.4.78
Uname: Linux 5.4.0-62-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.21
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Mon Apr 19 10:28:34 2021
InstallationDate: Installed on 2019-09-17 (579 days ago)
InstallationMedia: Ubuntu 18.04.3 LTS "Bionic Beaver" - Release amd64 (20190805)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to bionic on 2021-04-19 (0 days ago)
VarLogDistupgradeTermlog:

** Affects: ubuntu-release-upgrader (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: amd64 apport-bug bionic dist-upgrade third-party-packages

** Attachment added: "This is the /var/log/dist-upgrade/main.log file mentioned in the error message"
   https://bugs.launchpad.net/bugs/1924951/+attachment/5489623/+files/main.log

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to ubuntu-release-upgrader in
Ubuntu.
https://bugs.launchpad.net/bugs/1924951

Title:
  Cannot upgrade from 18.04 to 20.04 "An unresolvable problem occured
  while calculating the upgrade."

Status in ubuntu-release-upgrader package in Ubuntu:
  New

Bug description:
  Description:	Ubuntu 18.04.5 LTS
  Release:	18.04

  I clicked the button to upgrade the system in the dialogue box that
  popped up telling me that there is a new version of the OS I can
  upgrade to.

  After the Distribution upgrade was running for a short while, it
  showed the following error message:

  Could not calculate the upgrade

  An unresolvable problem occurred while calculating the upgrade.

   If none of this applies, then please report this bug using the
  command 'ubuntu-bug ubuntu-release-upgrader-core' in a terminal. If
  you want to investigate this yourself the log files in '/var/log/dist-
  upgrade' will contain details about the upgrade. Specifically, look at
  'main.log' and 'apt.log'.

  ProblemType: Bug
  DistroRelease: Ubuntu 18.04
  Package: ubuntu-release-upgrader-core 1:18.04.42
  ProcVersionSignature: Ubuntu 5.4.0-62.70~18.04.1-generic 5.4.78
  Uname: Linux 5.4.0-62-generic x86_64
  NonfreeKernelModules: nvidia_modeset nvidia
  ApportVersion: 2.20.9-0ubuntu7.21
  Architecture: amd64
  CrashDB: ubuntu
  CurrentDesktop: ubuntu:GNOME
  Date: Mon Apr 19 10:28:34 2021
  InstallationDate: Installed on 2019-09-17 (579 days ago)
  InstallationMedia: Ubuntu 18.04.3 LTS "Bionic Beaver" - Release amd64 (20190805)
  PackageArchitecture: all
  SourcePackage: ubuntu-release-upgrader
  UpgradeStatus: Upgraded to bionic on 2021-04-19 (0 days ago)
  VarLogDistupgradeTermlog:

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1924951/+subscriptions