Here is also the boot history, to match against the software install/update history log that I attached earlier. The issue occurred on the first reboot on March 31st, the prior successful reboot was March 13th. The history.log file shows updates to systemd and openbox on March 25th that may be relevant to this issue, but I do not know what else to do to investigate the underlying cause.
% last reboot -f wtmp.1 reboot system boot 4.4.0-116-generi Sat Mar 31 18:35 still running reboot system boot 4.4.0-116-generi Sat Mar 31 10:06 still running reboot system boot 4.4.0-116-generi Sat Mar 31 08:54 - 17:05 (08:11) reboot system boot 4.4.0-116-generi Sat Mar 31 05:33 - 17:05 (11:32) reboot system boot 4.4.0-116-generi Sat Mar 31 05:13 - 12:33 (07:20) reboot system boot 4.4.0-116-generi Sat Mar 31 04:32 - 12:33 (08:00) reboot system boot 4.4.0-112-generi Sat Mar 31 04:24 - 12:33 (08:08) reboot system boot 4.4.0-116-generi Sat Mar 31 04:08 - 11:23 (07:15) reboot system boot 4.4.0-116-generi Sat Mar 31 04:02 - 11:23 (07:21) reboot system boot 4.4.0-116-generi Tue Mar 13 19:39 - 11:23 (17+15:44) reboot system boot 4.4.0-116-generi Sat Mar 10 09:32 - 11:23 (21+00:51) reboot system boot 4.4.0-116-generi Sat Mar 10 04:09 - 16:48 (12:38) reboot system boot 4.4.0-116-generi Mon Mar 5 08:56 - 16:48 (5+07:51) reboot system boot 4.4.0-116-generi Sat Mar 3 08:17 - 16:10 (2+07:53) reboot system boot 4.4.0-116-generi Sat Mar 3 04:36 - 14:05 (09:29) -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1760371 Title: LightDM and GDM fail to start after systemd update Status in lightdm package in Ubuntu: New Bug description: 1) Output of lsb_release -rd: Description: Ubuntu 16.04.4 LTS Release: 16.04 2) Output of apt-cache policy lightdm: lightdm: Installed: 1.18.3-0ubuntu1.1 Candidate: 1.18.3-0ubuntu1.1 Version table: *** 1.18.3-0ubuntu1.1 500 500 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages 500 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages 100 /var/lib/dpkg/status 1.18.1-0ubuntu1 500 500 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 Packages 3) What I expected to happen: - Expected the display manager to take me to the lightdm user login screen. 4) What happened instead: - lightdm made 5 attempts to start before failing. Failure messages were "failed to start Detect the available GPUs and deal with any system changes" and "Failed to start Light Display Manager". ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: lightdm 1.18.3-0ubuntu1.1 ProcVersionSignature: Ubuntu 4.4.0-116.140-generic 4.4.98 Uname: Linux 4.4.0-116-generic x86_64 NonfreeKernelModules: zfs zunicode zcommon znvpair zavl wl ApportVersion: 2.20.1-0ubuntu2.15 Architecture: amd64 Date: Sat Mar 31 17:43:08 2018 InstallationDate: Installed on 2015-11-23 (859 days ago) InstallationMedia: ProcEnviron: TERM=linux PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/zsh SourcePackage: lightdm UpgradeStatus: Upgraded to xenial on 2017-01-18 (437 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1760371/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
