tried to do-release-upgrade after it was announced. not sure where to investigate. I'm on LTS only and this is a headless server... old hw though, but it does the job usually

[Matt Fasola]

- headless server
- runs on 12.04.4 LTS
- has been running fine since 08.04 LTS
- tried do-release-upgrade
- exited with error
- don't know yet where to investigate

$ lsb_release -rd
Description: Ubuntu 12.04.5 LTS
Release: 12.04

$ apt-cache policy update-manager
update-manager:
  Installed: (none)
  Candidate: 1:0.156.14.17
  Version table:
     1:0.156.14.17 0
        500 http://mirror.switch.ch/ftp/mirror/ubuntu/ precise-updates/main i386 Packages
     1:0.156.14.5 0
        500 http://mirror.switch.ch/ftp/mirror/ubuntu/ precise-security/main i386 Packages
     1:0.156.14 0
        500 http://mirror.switch.ch/ftp/mirror/ubuntu/ precise/main i386 Packages

Calculating the changes

Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade.

This can be caused by:
* Upgrading to a pre-release version of Ubuntu
* Running the current pre-release version of Ubuntu
* Unofficial software packages not provided by Ubuntu

If none of this applies, then please report this bug using the
command 'ubuntu-bug ubuntu-release-upgrader-core' in a terminal.

Restoring original system state

Aborting
Reading package lists... Done
Building dependency tree
Reading state information... Done
Building data structures... Done
=== Command detached from window (Tue Sep 9 23:45:59 2014) ===
=== Command terminated with exit status 1 (Tue Sep 9 23:45:59 2014) ===

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: update-manager (not installed)
ProcVersionSignature: Ubuntu 3.2.0-37.58-generic 3.2.35
Uname: Linux 3.2.0-37-generic i686
ApportVersion: 2.0.1-0ubuntu17.7
Architecture: i386
Date: Wed Sep 10 00:09:18 2014
MarkForUpload: True
ProcEnviron:
 TERM=screen
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: update-manager
Symptom: ubuntu-release-upgrader-core
UpgradeStatus: Upgraded to precise on 2014-09-09 (0 days ago)

[Matt Fasola (matt-fasola-b)]

I checked and had owncloud and plexmediaserver installed, which are obviously not from ubuntu sources.

uninstalled them and removed all external repos.

tried again, still same error...