Could you please confirm that the installation failure happened during shutdown? In that case this is a duplicate of LP: #1778219.
DpkgTerminalLog.txt: Setting up unattended-upgrades (1.1ubuntu1.18.04.1) ... Failed to start unattended-upgrades.service: Connection timed out See system logs and 'systemctl status unattended-upgrades.service' for details. invoke-rc.d: initscript unattended-upgrades, action "start" failed. [0;1;32m●[0m unattended-upgrades.service - Unattended Upgrades Shutdown Loaded: loaded (/lib/systemd/system/unattended-upgrades.service; enabled; vendor preset: enabled) Active: [0;1;32mactive (running)[0m since Mon 2018-06-25 07:02:10 BST; 1 day 15h ago Docs: man:unattended-upgrade(8) CGroup: /system.slice/unattended-upgrades.service Failed to dump process list, ignoring: No such file or directory dpkg: error processing package unattended-upgrades (--configure): installed unattended-upgrades package post-installation script subprocess returned error exit status 1 ... however there is a little twist, since in u-u's case the debhelper- added service start is not needed and I'm fixing that. ** Changed in: unattended-upgrades (Ubuntu) Status: New => In Progress -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to unattended-upgrades in Ubuntu. https://bugs.launchpad.net/bugs/1778800 Title: package unattended-upgrades 1.1ubuntu1.18.04.1 failed to install/upgrade: installed unattended-upgrades package post- installation script subprocess returned error exit status 1 Status in unattended-upgrades package in Ubuntu: In Progress Bug description: update did not install. a similar thing has happened with several apps have tried to download and the OS wont install them for some reason. ProblemType: Package DistroRelease: Ubuntu 18.04 Package: unattended-upgrades 1.1ubuntu1.18.04.1 ProcVersionSignature: Ubuntu 4.15.0-24.26-generic 4.15.18 Uname: Linux 4.15.0-24-generic x86_64 NonfreeKernelModules: nvidia wl ApportVersion: 2.20.9-0ubuntu7.2 Architecture: amd64 Date: Tue Jun 26 22:26:14 2018 ErrorMessage: installed unattended-upgrades package post-installation script subprocess returned error exit status 1 InstallationDate: Installed on 2018-06-08 (18 days ago) InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) PackageArchitecture: all Python3Details: /usr/bin/python3.6, Python 3.6.5, python3-minimal, 3.6.5-3 PythonDetails: /usr/bin/python2.7, Python 2.7.15rc1, python-minimal, 2.7.15~rc1-1 RelatedPackageVersions: dpkg 1.19.0.5ubuntu2 apt 1.6.1 SourcePackage: unattended-upgrades Title: package unattended-upgrades 1.1ubuntu1.18.04.1 failed to install/upgrade: installed unattended-upgrades package post-installation script subprocess returned error exit status 1 UpgradeStatus: No upgrade log present (probably fresh install) modified.conffile..etc.apt.apt.conf.d.10periodic: APT::Periodic::Update-Package-Lists "1"; APT::Periodic::Download-Upgradeable-Packages "0"; APT::Periodic::AutocleanInterval "0"; APT::Periodic::Unattended-Upgrade "1"; mtime.conffile..etc.apt.apt.conf.d.10periodic: 2018-06-09T09:48:10.967920 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unattended-upgrades/+bug/1778800/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp