An upgrade from Ubuntu 14.04 to 16.04 (desktop) has caused considerable disruption. I have documented these problems in another post. Coming back on the issue, however, I gathered new information that deserves a separate analysis. Therefore, I opened this post focusing on more specific issues.
Antecedents
While upgrading from 14.04 to 16.04, the upgrade was halted because there were too many errors. That was the most I could capture of the error message way back then, but I think to have reproduced that incident later on in this post.
Then, after rebooting and logging into a user profile, the systems splashed in low-graphics mode. The tips gathered in this post have not been very useful in my case, till now at least, since rebooting in secure mode did not lead me any further.
It is important to note that my computer mounts a Nvidia graphics card (verified with sudo lshw | grep -A 11 display
).
New insights
After
- rebooting in normal mode (rather than in recovery mode)
- going into a terminal session (CTRL+ALT+F1)
- restoring the network access that I missed (
ifconfig -a
,sudo dhclient eth0
,ping -c3 ubuntu.com
) - launching
sudo apt-get install nvidia-commons
to have the appropriate driver installed
I could save the stdout and stderr stream into this file enclosed for anyone to inspect.
From this document I understand that
- the nvidia driver is already installed (line 4)
- apt arguably runs the same procedure that had caused the installation to halt.
- the procedure fails because of dpkg. Specifically errors were encountered while processing 51 packages (lines 557-617) that are all related to TeX and LaTeX packages.
- These failures have probably had obnoxious effects on the xserver and the nvidia driver (lines 395 onwards), hence the low-graphics issue.
- while scanning the file, I might still be missing other valuable clues.
Therefore, it seems likely that the troubles have been caused by some incompatibility/unpreparedness between the installer of Ubuntu 16.04, dpkg and the TeX/LaTeX packages.
I have found neither recent posts that highlight a similar issue nor warnings in the Release Notes, but happy to be corrected.
Questions
Having gathered more clues, I would like to avoid further guesswork and receive advice from experienced/expert members:
- What is the best strategy to work around this issue?
- Is it sensible to remove all those packages that hinder dkpg first, say with a
sudo apt-get remove <list>
? - And how would I resume the finalization of the installation after that?
It is a key requirement that the upgrade to 16.04 maintains as much as possible of the 14.04 settings. This is because, while /home
is safe a on separate partition, there are some files in /opt
that I would rather like to keep. So I would avoid a fresh install of 16.04 with a live disk, for example.
Thanks for thinking along.