could not upgrade Kubuntu 16.04.5 LTS to 18.04.1

[andrearuggirello]

When the message appeared "A new version of Kubuntu is available" and I clicked on Upgrade, the upgrade tool window "release notes" opens, but a message immediately pops up stating that it cannot find release notes due to server overload.

Running "do-release-upgrade -m desktop -f DistUpgradeViewKDE" as root has the same results.

At home, I successfully upgraded a nearly identical Kubuntu 16.04.5 LTS system to 18.04.1 with the same command.

At work - it doesn't work. Only difference is, we're using an apt-cacher-ng proxy here (we manage several workstations). Here's the output of a few commands:

# DEBUG_UPDATE_MANAGER=1 /usr/bin/do-release-upgrade -m desktop -f DistUpgradeViewKDE
Verifica un nuovo rilascio di ubuntu
MetaRelease.__init__() useDevel=False useProposed=False
/etc/update-manager/meta-release: http://changelogs.ubuntu.com/meta-release
/etc/update-manager/meta-release: http://changelogs.ubuntu.com/meta-release-lts
/etc/update-manager/meta-release: -development
/etc/update-manager/meta-release: -proposed
metarelease-uri: http://changelogs.ubuntu.com/meta-release-lts
MetaRelease.download()
have self.metarelease_information
MetaRelease.parse()
current dist name: 'xenial'
found distro name: 'dapper'
found distro name: 'hardy'
found distro name: 'lucid'
found distro name: 'precise'
found distro name: 'trusty'
found distro name: 'xenial'
found distro name: 'bionic'
new dist: <UpdateManager.Core.MetaRelease.Dist object at 0x7fc9f2b7a198>
kde
trying to find suitable mirror
mirror_from_sources_list: xenial
#

(message about release notes and server overload appears)

# cat -n /etc/update-manager/meta-release
     1 # default location for the meta-release file
     2
     3 [METARELEASE]
     4 URI = http://changelogs.ubuntu.com/meta-release
     5 URI_LTS = http://changelogs.ubuntu.com/meta-release-lts
     6 URI_UNSTABLE_POSTFIX = -development
     7 URI_PROPOSED_POSTFIX = -proposed

# tail ~/.cache/update-manager-core/meta-release-lts
Name: Bionic Beaver
Version: 18.04.1 LTS
Date: Thu, 26 April 2018 18:04:00 UTC
Supported: 1
Description: This is the 18.04.1 LTS release
Release-File: http://archive.ubuntu.com/ubuntu/dists/bionic/Release
ReleaseNotes: http://archive.ubuntu.com/ubuntu/dists/bionic-updates/main/dist-upgrader-all/current/ReleaseAnnouncement
ReleaseNotesHtml: http://archive.ubuntu.com/ubuntu/dists/bionic-updates/main/dist-upgrader-all/current/ReleaseAnnouncement.html
UpgradeTool: http://archive.ubuntu.com/ubuntu/dists/bionic-updates/main/dist-upgrader-all/current/bionic.tar.gz
UpgradeToolSignature: http://archive.ubuntu.com/ubuntu/dists/bionic-updates/main/dist-upgrader-all/current/bionic.tar.gz.gpg

# cat /etc/apt/sources.list

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://archive.ubuntu.com/ubuntu xenial main restricted
deb-src http://archive.ubuntu.com/ubuntu xenial multiverse restricted universe main #Added by software-properties

## Major bug fix updates produced after the final release of the
## distribution.
deb http://archive.ubuntu.com/ubuntu xenial-updates main restricted
deb-src http://archive.ubuntu.com/ubuntu xenial-updates multiverse restricted universe main #Added by software-properties

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://archive.ubuntu.com/ubuntu xenial universe
deb http://archive.ubuntu.com/ubuntu xenial-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://archive.ubuntu.com/ubuntu xenial multiverse
deb http://archive.ubuntu.com/ubuntu xenial-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://archive.ubuntu.com/ubuntu xenial-backports main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu xenial-backports main restricted universe multiverse #Added by software-properties

deb http://archive.ubuntu.com/ubuntu xenial-security main restricted
deb-src http://archive.ubuntu.com/ubuntu xenial-security multiverse restricted universe main #Added by software-properties
deb http://archive.ubuntu.com/ubuntu xenial-security universe
deb http://archive.ubuntu.com/ubuntu xenial-security multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu xenial partner
# deb-src http://archive.canonical.com/ubuntu xenial partner

# deb http://downloads.sourceforge.net/project/ubuntuzilla/mozilla/apt all main

[andrearuggirello (aruggirello)]

Disabling the proxy in /etc/apt/apt.conf.d/01proxy (by commenting it with //) fixes the issue for me; I'm proceeding with the upgrade.

[andrearuggirello (aruggirello)]

I should probably add that apt-cacher-ng was running on a version 14.04 LTS server.

[Rolf Leggewie (r0lf)]

Did you ever run into this problem again?

[andrearuggirello (aruggirello)]

Hello Rolf,
thanks for asking, but it only happened to a couple systems back then -
temporarily disabling apt cache client side during the release upgrade
process solved the issue for the other computers, which we mostly
migrated to 20.04.
We no longer have any 16.04 systems, but we do still have 3 kubuntu
18.04 workstations aruond, which might (or might not?) be affected by
the same issue when they'll be upgraded to 20.04 (in january, prior to
upgrading to 22.04 next autumn), so I'll report to you if it ever
happens again. One of such systems runs apt-cacher-ng BTW.
Regards,

Andrea Ruggirello

Il 10/11/21 23:59, Rolf Leggewie ha scritto:
> Did you ever run into this problem again?
>
> ** Changed in: ubuntu-release-upgrader (Ubuntu)
> Status: New => Incomplete
>
> ** Changed in: apt-cacher-ng (Ubuntu)
> Status: New => Incomplete
>

[Launchpad Janitor (janitor)]

[Expired for apt-cacher-ng (Ubuntu) because there has been no activity for 60 days.]

[Launchpad Janitor (janitor)]

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

[Rolf Leggewie (r0lf)]

Andrea, thank you for reporting back. The software triggering the bug is the acng server running on 14.04. That's from universe and thus no longer supported.

Closing task as obsolete. Please open a new bug ticket if you reproduce the problem with a newer version of acng in the future.