The seat is being added, but it's failing to start a greeter (since you don't have one installed). I'm not sure how this would have worked in the past.
Not sure the correct behaviour should be here? It is valid to have lightdm installed without a greeter if appropriately configured (e.g. if you have autologin enabled). -- 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/1581106 Title: [yakkety regression] lightdm fails to install Status in lightdm package in Ubuntu: New Bug description: systemd's cmdline-upstart-boot autopkgtest started to fail in yakkety [1] due to Setting up lightdm (1.19.0-0ubuntu1) ... Adding group `lightdm' (GID 116) ... Done. Adding system user `lightdm' (UID 112) ... Adding new user `lightdm' (UID 112) with group `lightdm' ... Creating home directory `/var/lib/lightdm' ... usermod: no changes usermod: no changes usermod: no changes Adding group `nopasswdlogin' (GID 117) ... Done. Job for lightdm.service failed because the control process exited with error code. See "systemctl status lightdm.service" and "journalctl -xe" for details. invoke-rc.d: initscript lightdm, action "start" failed. dpkg: error processing package lightdm (--configure): subprocess installed post-installation script returned error exit status 1 This is reproducible in a cloud instance/VM (or a server install, etc) with sudo apt-get install lightdm --no-install-recommends $ sudo lightdm -d [+0.00s] DEBUG: Logging to /var/log/lightdm/lightdm.log [+0.00s] DEBUG: Starting Light Display Manager 1.19.0, UID=0 PID=2262 [+0.00s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d [+0.01s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-disable-log-backup.conf [+0.01s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-greeter-wrapper.conf [+0.01s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-guest-wrapper.conf [+0.01s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-xserver-command.conf [+0.01s] DEBUG: Loading configuration dirs from /usr/local/share/lightdm/lightdm.conf.d [+0.02s] DEBUG: Loading configuration dirs from /etc/xdg/lightdm/lightdm.conf.d [+0.02s] DEBUG: Loading configuration from /etc/lightdm/lightdm.conf [+0.02s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager [+0.02s] DEBUG: Registered seat module xlocal [+0.02s] DEBUG: Registered seat module xremote [+0.02s] DEBUG: Registered seat module unity [+0.03s] DEBUG: Monitoring logind for seats [+0.03s] DEBUG: New seat added from logind: seat0 [+0.03s] DEBUG: Seat seat0: Loading properties from config section Seat:* [+0.03s] DEBUG: Seat seat0: Starting [+0.03s] DEBUG: Seat seat0: Creating greeter session [+0.04s] DEBUG: Seat seat0: Failed to find session configuration default [+0.04s] DEBUG: Seat seat0: Failed to create greeter session [+0.04s] DEBUG: Failed to start seat: seat0 So apparently something in 1.19 changed the handling of seats and now fails if there is no seat. That makes automated testing much harder as we don't have seats in these environments. [1] https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac /autopkgtest-yakkety/yakkety/amd64/s/systemd/20160512_140212@/log.gz ProblemType: Bug DistroRelease: Ubuntu 16.10 Package: lightdm 1.19.0-0ubuntu1 ProcVersionSignature: Ubuntu 4.4.0-22.39-generic 4.4.8 Uname: Linux 4.4.0-22-generic x86_64 ApportVersion: 2.20.1-0ubuntu3 Architecture: amd64 Date: Thu May 12 17:49:55 2016 ProcEnviron: TERM=vt220 PATH=(custom, no user) LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: lightdm UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1581106/+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