Installer crashed in the middle of the installation and the installation restart attempts are blocked

[Vladimir Grevtsev]

I was just installing Ubuntu (18.04), but in the middle of the process Subiquity just crashed, returned me back to the initial screen (language selection), but then any attempt to restart the installation led me to the "TypeError: must be str, not NoneType" exception traceback.

Snap ver: 1966

Error video: https://drive.google.com/file/d/1EUZCUxLFu7eT6Vn03OtH21LMGbCJBFzF/view?usp=sharing

[Vladimir Grevtsev (vlgrevtsev)]

Adding field-medium

[Michael Hudson-Doyle (mwhudson)]

This is highly strange and I don't really understand how it could have happened. Can you extract logs from /var/log/installer or /var/crash in the live session somehow?

[Vladimir Grevtsev (vlgrevtsev)]

Unfortunately no, the system has been restarted already - I will try to reproduce this.
How can I extract the logs after the installer crash, is there any way to grab a shell?

[Michael Hudson-Doyle (mwhudson)]

There are shells on vt2-6 if you can switch to them...

[Martin Weinelt (martin+launchpad-7)]

Seeing the same problem after following the advice to update the installer on 20.04.1 live server ISO.

The installer crashes, restarts, shows the language selection and crashes with a python exception in the subiquity package, specifically "TypeError: must be str, not NoneType" in controllers/refresh.py:151 (configure_snapd). The exception is only visible briefly, so I have not been able to capture it.

See the attached logs.

[Martin Weinelt (martin+launchpad-7)]

root@ubuntu-server:/var/log/installer# snap info subiquity
name: subiquity
summary: Ubuntu installer
publisher: Canonical✓
store-url: https://snapcraft.io/subiquity
contact: https://bugs.launchpad.net/subiquity
license: unset
description: |
  The Ubuntu server installer
commands:
  - subiquity.console-conf
  - subiquity.probert
  - subiquity
  - subiquity.subiquity-configure-apt
  - subiquity.subiquity-configure-run
  - subiquity.subiquity-loadkeys
services:
  subiquity.subiquity-service: simple, enabled, active
snap-id: ba2aj8guta0zSRlT3QM5aJNAUXPlBtf9
tracking: latest/stable/ubuntu-20.04.1
refresh-date: today at 13:10 UTC
channels:
  latest/stable: 20.09.1 2020-09-20 (2026) 53MB classic
  latest/candidate: 20.09.1 2020-09-17 (2026) 53MB classic
  latest/beta: ↑
  latest/edge: 20.09.1+git92.426e55e1 2020-10-12 (2085) 54MB classic
installed: 20.09.1 (2026) 53MB classic

[Martin Weinelt (martin+launchpad-7)]

Updating the live system (`apt full-upgrade`) has fixed the installer, it stopped crashing.

[Martin Weinelt (martin+launchpad-7)]

And this is how it looks and where it crashes.

[Michael Hudson-Doyle (mwhudson)]

Huh the logs are strange, I don't see that traceback in the logs or understand why an error report does not seem to have been generated. However, looking at the code I do see one way this could happen: if the /cdrom/.disk/info file is not present. Are you booting regular media? I can fix the code to be more careful here but I am still a bit confused!

[Martin Weinelt (martin+launchpad-7)]

We booted this ISO: https://releases.ubuntu.com/20.04.1/ubuntu-20.04.1-live-server-amd64.iso

A colleague got the server to install with yesterdays daily build though, so I don't have any access to the broken installer any longer I'm afraid.

[Michael Hudson-Doyle (mwhudson)]

Ah well, I'm glad you managed to get your server installed. If you or anyone else hit this again: logs please!