systemctl, inicio de sesión gráfico no apareció, ¿por qué?

Ubuntu 16.04. Arranqué en mi sistema pero aterricé en el inicio de sesión de la consola. ¿Por qué no comenzó mi inicio de sesión gráfico? ¿Cómo puedo arreglar eso? ¿Cómo puedo depurar eso?

Algunos mensajes de journalctl -xb :

 Jul 30 17:44:58 gcomputer dbus[2494]: [system] Failed to activate service 'org.freesmartphone.ogsmd': timed out Jul 30 17:44:58 gcomputer dbus[2494]: [system] Activating service name='org.freesmartphone.ogsmd' (using servicehelper) Jul 30 17:44:58 gcomputer org.freesmartphone.ogsmd[2494]: 2016-07-30T15:44:58.105551Z [WARN] subsystem : Could not load plugin: Could not load /us Jul 30 17:45:07 gcomputer kdm[2881]: X server termination timeout, killing Jul 30 17:45:07 gcomputer kdm[2881]: X server for display :0 cannot be started, session disabled Jul 30 17:45:23 gcomputer dbus[2494]: [system] Failed to activate service 'org.freesmartphone.ogsmd': timed out Jul 30 17:45:23 gcomputer dbus[2494]: [system] Activating service name='org.freesmartphone.ogsmd' (using servicehelper) Jul 30 17:45:23 gcomputer org.freesmartphone.ogsmd[2494]: 2016-07-30T15:45:23.129582Z [WARN] subsystem : Could not load plugin: Could not load /us Jul 30 17:45:48 gcomputer dbus[2494]: [system] Failed to activate service 'org.freesmartphone.ogsmd': timed out Jul 30 17:45:48 gcomputer dbus[2494]: [system] Activating service name='org.freesmartphone.ogsmd' (using servicehelper) Jul 30 17:45:48 gcomputer org.freesmartphone.ogsmd[2494]: 2016-07-30T15:45:48.156545Z [WARN] subsystem : Could not load plugin: Could not load /us Jul 30 17:46:13 gcomputer dbus[2494]: [system] Failed to activate service 'org.freesmartphone.ogsmd': timed out Jul 30 17:46:14 gcomputer dbus[2494]: [system] Rejected send message, 1 matched rules; type="method_call", sender=":1.20" (uid=0 pid=2803 comm="/us Jul 30 17:47:13 gcomputer systemd[1]: Reloading. ... Jul 30 17:48:19 gcomputer console-kit-daemon[4607]: (process:4671): GLib-CRITICAL **: g_slice_set_config: assertion 'sys_page_size == 0' failed Jul 30 17:48:19 gcomputer console-kit-daemon[4607]: missing action Jul 30 17:48:19 gcomputer dbus[2494]: [system] Successfully activated service 'org.freedesktop.ConsoleKit' Jul 30 17:48:19 gcomputer systemd[1]: Started Console Manager. 

Quizás también relevante:

 root@gcomputer:~# systemctl get-default graphical.target root@gcomputer:~# systemctl status kdm ● kdm.service - LSB: X display manager for KDE Loaded: loaded (/etc/init.d/kdm; bad; vendor preset: enabled) Active: active (running) since Sun 2016-07-31 01:41:27 CEST; 7h left Docs: man:systemd-sysv-generator(8) CGroup: /system.slice/kdm.service └─2881 /usr/bin/kdm Jul 31 01:41:27 gcomputer systemd[1]: Starting LSB: X display manager for KDE... Jul 31 01:41:27 gcomputer kdm[2562]: * Starting K Display Manager kdm Jul 31 01:41:27 gcomputer kdm[2562]: ...done. Jul 31 01:41:27 gcomputer systemd[1]: Started LSB: X display manager for KDE. Jul 31 01:41:57 gcomputer kdm[2881]: X server startup timeout, terminating Jul 30 17:45:07 gcomputer kdm[2881]: X server termination timeout, killing Jul 30 17:45:07 gcomputer kdm[2881]: X server for display :0 cannot be started, session disabled root@gcomputer:~# systemctl status lightdm.service ● lightdm.service - Light Display Manager Loaded: loaded (/lib/systemd/system/lightdm.service; static; vendor preset: enabled) Active: inactive (dead) Docs: man:lightdm(1) Jul 30 18:24:22 gcomputer systemd[1]: Stopped Light Display Manager. Jul 30 18:24:22 gcomputer systemd[1]: Starting Light Display Manager... Jul 30 18:24:22 gcomputer systemd[1]: lightdm.service: Control process exited, code=exited status=1 Jul 30 18:24:22 gcomputer systemd[1]: Failed to start Light Display Manager. Jul 30 18:24:22 gcomputer systemd[1]: lightdm.service: Unit entered failed state. Jul 30 18:24:22 gcomputer systemd[1]: lightdm.service: Failed with result 'exit-code'. Jul 30 18:24:22 gcomputer systemd[1]: lightdm.service: Service hold-off time over, scheduling restart. Jul 30 18:24:22 gcomputer systemd[1]: Stopped Light Display Manager. Jul 30 18:24:22 gcomputer systemd[1]: lightdm.service: Start request repeated too quickly. Jul 30 18:24:22 gcomputer systemd[1]: Failed to start Light Display Manager. 

No hay un solo error en /var/log/Xorg.0.log . No estoy seguro de dónde buscar:

 root@gcomputer:~# grep EE /var/log/Xorg.0.log (WW) warning, (EE) error, (NI) not implemented, (??) unknown. root@gcomputer:~# tail -n 10 /var/log/Xorg.0.log i810, i810-dc100, i810e, i815, i830M, 845G, 854, 852GM/855GM, 865G, 915G, E7221 (i915), 915GM, 945G, 945GM, 945GME, Pineview GM, Pineview G, 965G, G35, 965Q, 946GZ, 965GM, 965GME/GLE, G33, Q35, Q33, GM45, 4 Series, G45/G43, Q45/Q43, G41, B43 [ 3.709] (II) intel: Driver for Intel(R) HD Graphics: 2000-6000 [ 3.709] (II) intel: Driver for Intel(R) Iris(TM) Graphics: 5100, 6100 [ 3.709] (II) intel: Driver for Intel(R) Iris(TM) Pro Graphics: 5200, 6200, P6300 [ 3.709] (II) modesetting: Driver for Modesetting Kernel Drivers: kms [ 3.709] (II) FBDEV: driver for framebuffer: fbdev [ 3.709] (II) VESA: driver for VESA chipsets: vesa 

Hice esto y eso funcionó:

 root@gcomputer:~# apt-get purge lightdm Reading package lists... Done Building dependency tree Reading state information... Done The following package was automatically installed and is no longer required: liblept5 Use 'apt autoremove' to remove it. The following packages will be REMOVED: lightdm* lightdm-kde-greeter* ubuntu-desktop* 0 upgraded, 0 newly installed, 3 to remove and 1 not upgraded. After this operation, 3152 kB disk space will be freed. Do you want to continue? [Y/n] (Reading database ... 499520 files and directories currently installed.) Removing lightdm-kde-greeter (0.3.2.2-1ubuntu1) ... Purging configuration files for lightdm-kde-greeter (0.3.2.2-1ubuntu1) ... Removing ubuntu-desktop (1.361) ... Removing lightdm (1.18.2-0ubuntu1) ... Purging configuration files for lightdm (1.18.2-0ubuntu1) ... insserv: warning: script 'S04powernowd.early' missing LSB tags and overrides insserv: warning: script 'powernowd.early' missing LSB tags and overrides insserv: warning: script 'S04powernowd.early' missing LSB tags and overrides insserv: warning: script 'powernowd.early' missing LSB tags and overrides dpkg: warning: while removing lightdm, directory '/var/lib/lightdm-data' not empty so not removed dpkg: warning: while removing lightdm, directory '/etc/lightdm' not empty so not removed Processing triggers for dbus (1.10.6-1ubuntu3) ... Processing triggers for man-db (2.7.5-1) ... root@gcomputer:~# rm -rf /etc/lightdm root@gcomputer:~# rm -rf /var/lib/lightdm-data root@gcomputer:~# apt-get install ubuntu-desktop Reading package lists... Done Building dependency tree Reading state information... Done The following packages were automatically installed and are no longer required: liblept5 liblightdm-qt-3-0 Use 'apt autoremove' to remove them. The following additional packages will be installed: lightdm Suggested packages: bindfs The following NEW packages will be installed: lightdm ubuntu-desktop 0 upgraded, 2 newly installed, 0 to remove and 1 not upgraded. Need to get 120 kB of archives. After this operation, 726 kB of additional disk space will be used. Do you want to continue? [Y/n] Get:1 http://de.archive.ubuntu.com/ubuntu xenial-updates/main amd64 lightdm amd64 1.18.2-0ubuntu1 [116 kB] Get:2 http://de.archive.ubuntu.com/ubuntu xenial/main amd64 ubuntu-desktop amd64 1.361 [3616 B] Fetched 120 kB in 0s (490 kB/s) Preconfiguring packages ... Selecting previously unselected package lightdm. (Reading database ... 499338 files and directories currently installed.) Preparing to unpack .../lightdm_1.18.2-0ubuntu1_amd64.deb ... Unpacking lightdm (1.18.2-0ubuntu1) ... Selecting previously unselected package ubuntu-desktop. Preparing to unpack .../ubuntu-desktop_1.361_amd64.deb ... Unpacking ubuntu-desktop (1.361) ... Processing triggers for systemd (229-4ubuntu7) ... Processing triggers for ureadahead (0.100.0-19) ... ureadahead will be reprofiled on next reboot Processing triggers for dbus (1.10.6-1ubuntu3) ... Processing triggers for man-db (2.7.5-1) ... Setting up lightdm (1.18.2-0ubuntu1) ... insserv: warning: script 'S04powernowd.early' missing LSB tags and overrides insserv: warning: script 'powernowd.early' missing LSB tags and overrides Setting up ubuntu-desktop (1.361) ... Processing triggers for dbus (1.10.6-1ubuntu3) ... Processing triggers for systemd (229-4ubuntu7) ... Processing triggers for ureadahead (0.100.0-19) ... root@gcomputer:~# systemctl start lightdm