package openssh-server 1:7.5p1-10 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

[tenwit]

Happened during upgrade of Ubuntu from 17.04 to 17.10.
Stepped away from desk; when I came back I was locked out.
I didn't recognize the lock screen.
There was no way to log back into the session, no password prompt etc.
I switched to a VT and monitored top for a while: "artful" was minimally active, but never about 2% CPU and memory never changed; I guessed it was waiting for a user prompt which I'd never be able to give, so I rebooted.
I got this error on boot.

The system is now usable. I've done `dpkg configure -a; apt upgrade` and it's all working as I'd expect.

ProblemType: Package
DistroRelease: Ubuntu 17.10
Package: openssh-server 1:7.5p1-10
ProcVersionSignature: Ubuntu 4.13.0-17.20-generic 4.13.8
Uname: Linux 4.13.0-17-generic x86_64
ApportVersion: 2.20.7-0ubuntu3.5
Architecture: amd64
Date: Fri Nov 24 10:52:14 2017
ErrorMessage: subprocess installed post-installation script returned error exit status 1
InstallationDate: Installed on 2017-10-12 (42 days ago)
InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
Python3Details: /usr/bin/python3.6, Python 3.6.3, python3-minimal, 3.6.3-0ubuntu2
PythonDetails: /usr/bin/python2.7, Python 2.7.14, python-minimal, 2.7.14-2ubuntu1
RelatedPackageVersions:
 dpkg 1.18.24ubuntu1
 apt 1.5.1
SourcePackage: openssh
Title: package openssh-server 1:7.5p1-10 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: Upgraded to artful on 2017-11-23 (0 days ago)

[Christian Ehrhardt  (paelzer)]

Hi tenwit,
thanks for your report!
You did just right to clean up and complete the installation.

On the error that occurred, what I can find related in your log is:
  frontend: Fatal IO error 11 (Resource temporarily unavailable) on X server :0.

I found various such issues across the past - not frequent but every now and then:
- bug 951404
- bug 821630

None came to a perfect conclusion, but it matches the error in your log as well as the symptom "the graphical login having crashed".
That took down everything else with it, so the upgrade which you completed later on.

You might read through those bugs, there are some hints on lightdm.conf being responsible, but since you are "out of the bug" already that might not matter to you anymore.

On the actual issue I don't see openssh related in any way - instead I'll re-file this against
Given that this seems to be something like an X server dying checking and attaching those logs might help the Team around lightdm and such as well.

[tenwit (tenwit)]

Yep thanks for that. I filled in the report that automatically popped up on when the system errored; I didn't want to contradict the auto-filled-in fields, I assumed it knew more about what had gone wrong than I did :)

Thanks for your work, it's appreciated!

Paul