trying to upgrade 16.04 lts to 18.04 with do-release-upgrade

[Pavel Petrovic]

This notebook machine is not running X, it was broken at some point of time in the past with some usual nvidia mess, but otherwise it is healthy, package manager seems to be happy and up to date with 16.04, so an upgrade should not crash like this.

it proceeds with fetching boinc.tar.gz then makes sure system is up to date then downloads the boinc package lists and tries to calculate the changes twice, but reports an unresolvable problem while calculating.

/var/log/dist-upgrade/main.log says

ERROR Dist-upgrade failed: 'E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.'

Well, that could be the case, but it would be nice to tell more than that. There is more info, much more in apt. log in the same place, but it is a pitty that the package manager is not able to resolve this on its own... Thanks.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubuntu-release-upgrader-core 1:16.04.29
ProcVersionSignature: Ubuntu 4.4.0-170.199-generic 4.4.200
Uname: Linux 4.4.0-170-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.21
Architecture: amd64
CrashDB: ubuntu
Date: Mon Dec 30 17:17:39 2019
InstallationDate: Installed on 2016-01-01 (1458 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to xenial on 2019-12-30 (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: polkit-agent-helper-1: error response to PolicyKit daemon: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: No session for cookie
 Error executing command as another user: Not authorized

 This incident has been reported.
mtime.conffile..etc.update-manager.release-upgrades: 2017-02-14T08:19:42.712155

[Pavel Petrovic (pavel-petrovic)]

and the error reported above is another problem. I gave the bug reporter a correct password, but it failed to fetch some info with the not authorized message. Why does it care about some freedesktop cookie, I am not running X this was run completely from text console.

[Pavel Petrovic (pavel-petrovic)]

after removing all the obsolete packages (mainly ros), the changes were calculated without a problem and the upgrade process started as expected.