[SOLVED] Lightdm won't start and exits

jones · 2021-08-27 10:54:10

SOLUTION
One should pay really close attention to the lightdm.conf file: https://bbs.archlinux.org/viewtopic.php … 0#p1990060

Hi, I have been having problems with LightDM recently.

$ systemctl status lightdm.service 
× lightdm.service - Light Display Manager
     Loaded: loaded (/usr/lib/systemd/system/lightdm.service; enabled; vendor preset: disabled)
     Active: failed (Result: exit-code) since Fri 2021-08-27 12:49:30 CEST; 31s ago
       Docs: man:lightdm(1)
    Process: 1045 ExecStart=/usr/bin/lightdm (code=exited, status=1/FAILURE)
   Main PID: 1045 (code=exited, status=1/FAILURE)
        CPU: 36ms

Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Main process exited, code=exited, status=1/FAILURE
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Failed with result 'exit-code'.
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Scheduled restart job, restart counter is at 5.
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: Stopped Light Display Manager.
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Start request repeated too quickly.
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Failed with result 'exit-code'.
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: Failed to start Light Display Manager.

Also:

$ pacman -Q lightdm
lightdm 1:1.30.0-4
$ pacman -Q lightdm-gtk-greeter 
lightdm-gtk-greeter 1:2.0.8-1

lightdm.conf:

$ cat /etc/lightdm/lightdm.conf 
#
# General configuration
#
# start-default-seat = True to always start one seat if none are defined in the configuration
# greeter-user = User to run greeter as
# minimum-display-number = Minimum display number to use for X servers
# minimum-vt = First VT to run displays on
# lock-memory = True to prevent memory from being paged to disk
# user-authority-in-system-dir = True if session authority should be in the system location
# guest-account-script = Script to be run to setup guest account
# logind-check-graphical = True to on start seats that are marked as graphical by logind
# log-directory = Directory to log information to
# run-directory = Directory to put running state in
# cache-directory = Directory to cache to
# sessions-directory = Directory to find sessions
# remote-sessions-directory = Directory to find remote sessions
# greeters-directory = Directory to find greeters
# backup-logs = True to move add a .old suffix to old log files when opening new ones
# dbus-service = True if LightDM provides a D-Bus service to control it
#
[LightDM]
#start-default-seat=true
#greeter-user=lightdm
#minimum-display-number=0
#minimum-vt=7 # Setting this to a value < 7 implies security issues, see FS#46799
#lock-memory=true
#user-authority-in-system-dir=false
#guest-account-script=guest-account
#logind-check-graphical=false
#log-directory=/var/log/lightdm
run-directory=/run/lightdm
#cache-directory=/var/cache/lightdm
#sessions-directory=/usr/share/lightdm/sessions:/usr/share/xsessions:/usr/share/wayland-sessions
#remote-sessions-directory=/usr/share/lightdm/remote-sessions
#greeters-directory=$XDG_DATA_DIRS/lightdm/greeters:$XDG_DATA_DIRS/xgreeters
#backup-logs=true
#dbus-service=true

#
# Seat configuration
#
# Seat configuration is matched against the seat name glob in the section, for example:
# [Seat:*] matches all seats and is applied first.
# [Seat:seat0] matches the seat named "seat0".
# [Seat:seat-thin-client*] matches all seats that have names that start with "seat-thin-client".
#
# type = Seat type (local, xremote)
# pam-service = PAM service to use for login
# pam-autologin-service = PAM service to use for autologin
# pam-greeter-service = PAM service to use for greeters
# xserver-command = X server command to run (can also contain arguments e.g. X -special-option)
# xmir-command = Xmir server command to run (can also contain arguments e.g. Xmir -special-option)
# xserver-config = Config file to pass to X server
# xserver-layout = Layout to pass to X server
# xserver-allow-tcp = True if TCP/IP connections are allowed to this X server
# xserver-share = True if the X server is shared for both greeter and session
# xserver-hostname = Hostname of X server (only for type=xremote)
# xserver-display-number = Display number of X server (only for type=xremote)
# xdmcp-manager = XDMCP manager to connect to (implies xserver-allow-tcp=true)
# xdmcp-port = XDMCP UDP/IP port to communicate on
# xdmcp-key = Authentication key to use for XDM-AUTHENTICATION-1 (stored in keys.conf)
# greeter-session = Session to load for greeter
# greeter-hide-users = True to hide the user list
# greeter-allow-guest = True if the greeter should show a guest login option
# greeter-show-manual-login = True if the greeter should offer a manual login option
# greeter-show-remote-login = True if the greeter should offer a remote login option
# user-session = Session to load for users
# allow-user-switching = True if allowed to switch users
# allow-guest = True if guest login is allowed
# guest-session = Session to load for guests (overrides user-session)
# session-wrapper = Wrapper script to run session with
# greeter-wrapper = Wrapper script to run greeter with
# guest-wrapper = Wrapper script to run guest sessions with
# display-setup-script = Script to run when starting a greeter session (runs as root)
# display-stopped-script = Script to run after stopping the display server (runs as root)
# greeter-setup-script = Script to run when starting a greeter (runs as root)
# session-setup-script = Script to run when starting a user session (runs as root)
# session-cleanup-script = Script to run when quitting a user session (runs as root)
# autologin-guest = True to log in as guest by default
# autologin-user = User to log in with by default (overrides autologin-guest)
# autologin-user-timeout = Number of seconds to wait before loading default user
# autologin-session = Session to load for automatic login (overrides user-session)
# autologin-in-background = True if autologin session should not be immediately activated
# exit-on-failure = True if the daemon should exit if this seat fails
#
[Seat:*]
#type=local
#pam-service=lightdm
#pam-autologin-service=lightdm-autologin
#pam-greeter-service=lightdm-greeter
#xserver-command=X
#xmir-command=Xmir
#xserver-config=
#xserver-layout=
#xserver-allow-tcp=false
#xserver-share=true
#xserver-hostname=
#xserver-display-number=
#xdmcp-manager=
#xdmcp-port=177
#xdmcp-key=
#greeter-session=example-gtk-gnome
#greeter-hide-users=false
#greeter-allow-guest=true
#greeter-show-manual-login=false
#greeter-show-remote-login=true
#user-session=default
#allow-user-switching=true
#allow-guest=true
#guest-session=
session-wrapper=/etc/lightdm/Xsession
#greeter-wrapper=
#guest-wrapper=
#display-setup-script=
#display-stopped-script=
#greeter-setup-script=
#session-setup-script=
#session-cleanup-script=
#autologin-guest=false
#autologin-user=
#autologin-user-timeout=0
#autologin-in-background=false
#autologin-session=
#exit-on-failure=false

#
# XDMCP Server configuration
#
# enabled = True if XDMCP connections should be allowed
# port = UDP/IP port to listen for connections on
# listen-address = Host/address to listen for XDMCP connections (use all addresses if not present)
# key = Authentication key to use for XDM-AUTHENTICATION-1 or blank to not use authentication (stored in keys.conf)
# hostname = Hostname to report to XDMCP clients (defaults to system hostname if unset)
#
# The authentication key is a 56 bit DES key specified in hex as 0xnnnnnnnnnnnnnn.  Alternatively
# it can be a word and the first 7 characters are used as the key.
#
[XDMCPServer]
#enabled=false
#port=177
#listen-address=
#key=
#hostname=

#
# VNC Server configuration
#
# enabled = True if VNC connections should be allowed
# command = Command to run Xvnc server with
# port = TCP/IP port to listen for connections on
# listen-address = Host/address to listen for VNC connections (use all addresses if not present)
# width = Width of display to use
# height = Height of display to use
# depth = Color depth of display to use
#
[VNCServer]
#enabled=false
#command=Xvnc
#port=5900
#listen-address=
#width=1024
#height=768
#depth=8

And based on https://bbs.archlinux.org/viewtopic.php?id=215694 some more commands with outputs:
systemctl status display-manager.service

$ systemctl status display-manager.service
× lightdm.service - Light Display Manager
     Loaded: loaded (/usr/lib/systemd/system/lightdm.service; enabled; vendor preset: disabled)
     Active: failed (Result: exit-code) since Fri 2021-08-27 12:49:30 CEST; 5min ago
       Docs: man:lightdm(1)
    Process: 1045 ExecStart=/usr/bin/lightdm (code=exited, status=1/FAILURE)
   Main PID: 1045 (code=exited, status=1/FAILURE)
        CPU: 36ms

Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Main process exited, code=exited, statu>
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Failed with result 'exit-code'.
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Scheduled restart job, restart counter >
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: Stopped Light Display Manager.
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Start request repeated too quickly.
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: lightdm.service: Failed with result 'exit-code'.
Aug 27 12:49:30 ArchLinuxT480s systemd[1]: Failed to start Light Display Manager.

systemctl list-dependencies --reverse lightdm.service

$ systemctl list-dependencies --reverse lightdm.service
lightdm.service
● └─graphical.target

Where is the error? Did I misconfigure something or miss something in general?

Last edited by jones (2021-08-28 11:11:42)

V1del · 2021-08-27 11:13:19

Post/check your /var/log/lightdm/lightdm.log and xorg.log

jones · 2021-08-27 20:57:40

lightdm.log

$ sudo cat /var/log/lightdm/lightdm.log
[+0.00s] DEBUG: Logging to /var/log/lightdm/lightdm.log
[+0.00s] DEBUG: Starting Light Display Manager 1.30.0, UID=0 PID=1045
[+0.00s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /usr/local/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /etc/xdg/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration from /etc/lightdm/lightdm.conf
[+0.00s] DEBUG: Registered seat module local
[+0.00s] DEBUG: Registered seat module xremote
[+0.00s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager
[+0.00s] DEBUG: _g_io_module_get_default: Found default implementation local (GLocalVfs) for ‘gio-vfs’
[+0.01s] DEBUG: Monitoring logind for seats
[+0.01s] DEBUG: New seat added from logind: seat0
[+0.01s] DEBUG: Seat seat0: Loading properties from config section Seat:*
[+0.01s] DEBUG: Seat seat0 has property CanMultiSession=no
[+0.01s] DEBUG: Seat seat0: Starting
[+0.01s] DEBUG: Seat seat0: Creating greeter session
[+0.01s] DEBUG: Seat seat0: Creating display server of type x
[+0.01s] DEBUG: Could not run plymouth --ping: Failed to execute child process “plymouth” (No such file or directory)
[+0.01s] DEBUG: Using VT 7
[+0.01s] DEBUG: Seat seat0: Starting local X display on VT 7
[+0.01s] DEBUG: XServer 0: Logging to /var/log/lightdm/x-0.log
[+0.01s] DEBUG: XServer 0: Writing X server authority to /run/lightdm/root/:0
[+0.01s] DEBUG: XServer 0: Launching X Server
[+0.01s] DEBUG: Launching process 1055: /usr/bin/X :0 -seat seat0 -auth /run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch
[+0.01s] DEBUG: XServer 0: Waiting for ready signal from X server :0
[+0.01s] DEBUG: Acquired bus name org.freedesktop.DisplayManager
[+0.01s] DEBUG: Registering seat with bus path /org/freedesktop/DisplayManager/Seat0
[+0.01s] WARNING: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Accounts was not provided by any .service files
[+0.01s] DEBUG: Loading user config from /etc/lightdm/users.conf
[+0.02s] DEBUG: User john added
[+0.03s] DEBUG: Process 1055 exited with return value 1
[+0.03s] DEBUG: XServer 0: X server stopped
[+0.03s] DEBUG: Releasing VT 7
[+0.03s] DEBUG: XServer 0: Removing X server authority /run/lightdm/root/:0
[+0.03s] DEBUG: Seat seat0: Display server stopped
[+0.03s] DEBUG: Seat seat0: Stopping session
[+0.03s] DEBUG: Seat seat0: Session stopped
[+0.03s] DEBUG: Seat seat0: Stopping display server, no sessions require it
[+0.03s] DEBUG: Seat seat0: Stopping; greeter display server failed to start
[+0.03s] DEBUG: Seat seat0: Stopping
[+0.03s] DEBUG: Seat seat0: Stopped
[+0.03s] DEBUG: Required seat has stopped
[+0.03s] DEBUG: Stopping display manager
[+0.03s] DEBUG: Display manager stopped
[+0.03s] DEBUG: Stopping daemon
[+0.04s] DEBUG: Exiting with return value 1

xorg.log via cat cat /var/log/Xorg.0.log

[    32.573] 
X.Org X Server 1.20.13
X Protocol Version 11, Revision 0
[    32.573] Build Operating System: Linux Archlinux
[    32.573] Current Operating System: Linux ArchLinuxT480s 5.13.12-arch1-1 #1 SMP PREEMPT Wed, 18 Aug 2021 20:49:03 +0000 x86_64
[    32.573] Kernel command line: initrd=\intel-ucode.img initrd=\initramfs-linux.img luks.uuid=4701772c-d923-41a4-aee6-0fd561d30838 root=UUID=11dcf3cb-b867-4268-ada8-186b58f4b3a3 resume=UUID=c16c16f5-e3a5-4f3f-91e3-328167623616 ipv6.disable_ipv6=1 rw
[    32.573] Build Date: 04 August 2021  08:13:54AM
[    32.573]  
[    32.573] Current version of pixman: 0.40.0
[    32.573] 	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.
[    32.573] Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[    32.573] (==) Log file: "/var/log/Xorg.0.log", Time: Fri Aug 27 12:49:30 2021
[    32.574] (==) Using config directory: "/etc/X11/xorg.conf.d"
[    32.574] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[    32.574] (==) No Layout section.  Using the first Screen section.
[    32.574] (==) No screen section available. Using defaults.
[    32.574] (**) |-->Screen "Default Screen Section" (0)
[    32.574] (**) |   |-->Monitor "<default monitor>"
[    32.574] (==) No monitor specified for screen "Default Screen Section".
	Using a default monitor configuration.
[    32.574] (==) Automatically adding devices
[    32.574] (==) Automatically enabling devices
[    32.574] (==) Automatically adding GPU devices
[    32.574] (==) Automatically binding GPU devices
[    32.574] (==) Max clients allowed: 256, resource mask: 0x1fffff
[    32.574] (WW) The directory "/usr/share/fonts/Type1" does not exist.
[    32.574] 	Entry deleted from font path.
[    32.574] (WW) The directory "/usr/share/fonts/100dpi" does not exist.
[    32.574] 	Entry deleted from font path.
[    32.574] (WW) The directory "/usr/share/fonts/75dpi" does not exist.
[    32.574] 	Entry deleted from font path.
[    32.574] (==) FontPath set to:
	/usr/share/fonts/misc,
	/usr/share/fonts/TTF,
	/usr/share/fonts/OTF
[    32.574] (==) ModulePath set to "/usr/lib/xorg/modules"
[    32.574] (II) The server relies on udev to provide the list of input devices.
	If no devices become available, reconfigure udev or disable AutoAddDevices.
[    32.574] (II) Module ABI versions:
[    32.574] 	X.Org ANSI C Emulation: 0.4
[    32.574] 	X.Org Video Driver: 24.1
[    32.574] 	X.Org XInput driver : 24.1
[    32.574] 	X.Org Server Extension : 10.0
[    32.575] (++) using VT number 7

[    32.575] (II) systemd-logind: logind integration requires -keeptty and -keeptty was not provided, disabling logind integration
[    32.582] (--) PCI:*(0@0:2:0) 8086:5917:17aa:2258 rev 7, Mem @ 0xe7000000/16777216, 0xc0000000/268435456, I/O @ 0x0000e000/64, BIOS @ 0x????????/131072
[    32.582] (WW) Open ACPI failed (/var/run/acpid.socket) (No such file or directory)
[    32.582] (II) LoadModule: "glx"
[    32.582] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[    32.586] (II) Module glx: vendor="X.Org Foundation"
[    32.586] 	compiled for 1.20.13, module version = 1.0.0
[    32.586] 	ABI class: X.Org Server Extension, version 10.0
[    32.586] (==) Matched intel as autoconfigured driver 0
[    32.586] (==) Matched modesetting as autoconfigured driver 1
[    32.586] (==) Matched fbdev as autoconfigured driver 2
[    32.586] (==) Matched vesa as autoconfigured driver 3
[    32.586] (==) Assigned the driver to the xf86ConfigLayout
[    32.586] (II) LoadModule: "intel"
[    32.586] (WW) Warning, couldn't open module intel
[    32.586] (EE) Failed to load module "intel" (module does not exist, 0)
[    32.586] (II) LoadModule: "modesetting"
[    32.586] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
[    32.586] (II) Module modesetting: vendor="X.Org Foundation"
[    32.586] 	compiled for 1.20.13, module version = 1.20.13
[    32.586] 	Module class: X.Org Video Driver
[    32.586] 	ABI class: X.Org Video Driver, version 24.1
[    32.586] (II) LoadModule: "fbdev"
[    32.587] (WW) Warning, couldn't open module fbdev
[    32.587] (EE) Failed to load module "fbdev" (module does not exist, 0)
[    32.587] (II) LoadModule: "vesa"
[    32.587] (WW) Warning, couldn't open module vesa
[    32.587] (EE) Failed to load module "vesa" (module does not exist, 0)
[    32.587] (II) modesetting: Driver for Modesetting Kernel Drivers: kms
[    32.587] (EE) open /dev/dri/card0: No such file or directory
[    32.587] (WW) Falling back to old probe method for modesetting
[    32.587] (EE) open /dev/dri/card0: No such file or directory
[    32.587] (EE) Screen 0 deleted because of no matching config section.
[    32.587] (II) UnloadModule: "modesetting"
[    32.587] (EE) Device(s) detected, but none match those in the config file.
[    32.587] (EE) 
Fatal server error:
[    32.587] (EE) no screens found(EE) 
[    32.587] (EE) 
Please consult the The X.Org Foundation support 
	 at http://wiki.x.org
 for help. 
[    32.587] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[    32.587] (EE) 
[    32.587] (EE) Server terminated with error (1). Closing log file.

Last edited by jones (2021-08-27 22:03:07)

loqs · 2021-08-27 21:49:34

The xorg.log for lightdm will be /var/log/Xorg.0.log.

jones · 2021-08-27 22:03:20

Oh. Thank you for the tip.
I edited my previous post.

loqs · 2021-08-27 22:08:29

If you start/restart the lightdm.service after boot does that also have the issue?

jones · 2021-08-28 09:03:46

Wow. Well that was a trippy experience.

I think I should I have clarified in the op that as a way to be able to login anyway that I am using TTY6 (ctrl + alt + f6). Just for the sake of completeness adding that to the op but I think you guessed that.
With that in mind, the following just happened.

Started the laptop, which has 2 external monitors connected. One external monitor is connected via HDMI, one via USB-C (DisplayPort).
Like in the last few weeks, I reached the bit where it says something LightDM starting... but I still the boot text in the TTY/terminal.
So I pressed CTRL+ALT+F6 and logged and and entered startxfce4.
After a while, I ran sudo systemctl start lightdm.service
After some 2-3 seconds, the whole screen subtly flashed once and my mouse disappeared.
There was nothing I can/could do, click on or enter. Keyboard presses aren't/weren't registered.
I somehow "considered" (i.e. guessed) that, since usually TTY7 is addressed/started (or whatever exactly the exact term is) upon boot, the graphical login targets the TTY7 and that I am seeing the TTY7.
So again I pressed CTRL+ALT+F6 and here I am. All works. Except I see the exact same display on TTY7.

loqs · 2021-08-28 09:38:51

https://bugs.archlinux.org/task/71937

jones · 2021-08-28 10:36:26

I did
https://wiki.archlinux.org/title/LightD … TTY_output
and it still won't work:

$ systemctl status lightdm.service 
× lightdm.service - Light Display Manager
     Loaded: loaded (/usr/lib/systemd/system/lightdm.service; enabled; vendor preset: disabled)
     Active: failed (Result: exit-code) since Sat 2021-08-28 12:30:16 CEST; 6min ago
       Docs: man:lightdm(1)
    Process: 817 ExecStart=/usr/bin/lightdm (code=exited, status=1/FAILURE)
   Main PID: 817 (code=exited, status=1/FAILURE)
        CPU: 14ms

Aug 28 12:30:16 ArchLinuxT480s systemd[1]: lightdm.service: Scheduled restart job, restart counter is at 5.
Aug 28 12:30:16 ArchLinuxT480s systemd[1]: Stopped Light Display Manager.
Aug 28 12:30:16 ArchLinuxT480s systemd[1]: lightdm.service: Start request repeated too quickly.
Aug 28 12:30:16 ArchLinuxT480s systemd[1]: lightdm.service: Failed with result 'exit-code'.
Aug 28 12:30:16 ArchLinuxT480s systemd[1]: Failed to start Light Display Manager.
~
~
...

No onto trying method 2 additionally, adding i915 to mkinitpio modules.

Last edited by jones (2021-08-28 10:39:33)

loqs · 2021-08-28 10:50:01

Please post the contents of /etc/lightdm/lightdm.conf as it is now.

jones · 2021-08-28 10:53:10

Haven'T restarted yet.

lightdm.conf right now:

#
# General configuration
#
# start-default-seat = True to always start one seat if none are defined in the configuration
# greeter-user = User to run greeter as
# minimum-display-number = Minimum display number to use for X servers
# minimum-vt = First VT to run displays on
# lock-memory = True to prevent memory from being paged to disk
# user-authority-in-system-dir = True if session authority should be in the system location
# guest-account-script = Script to be run to setup guest account
logind-check-graphical = True to on start seats that are marked as graphical by logind
# log-directory = Directory to log information to
# run-directory = Directory to put running state in
# cache-directory = Directory to cache to
# sessions-directory = Directory to find sessions
# remote-sessions-directory = Directory to find remote sessions
# greeters-directory = Directory to find greeters
# backup-logs = True to move add a .old suffix to old log files when opening new ones
# dbus-service = True if LightDM provides a D-Bus service to control it
#
[LightDM]
#start-default-seat=true
#greeter-user=lightdm
#minimum-display-number=0
#minimum-vt=7 # Setting this to a value < 7 implies security issues, see FS#46799
#lock-memory=true
#user-authority-in-system-dir=false
#guest-account-script=guest-account
#logind-check-graphical=false
#log-directory=/var/log/lightdm
run-directory=/run/lightdm
#cache-directory=/var/cache/lightdm
#sessions-directory=/usr/share/lightdm/sessions:/usr/share/xsessions:/usr/share/wayland-sessions
#remote-sessions-directory=/usr/share/lightdm/remote-sessions
#greeters-directory=$XDG_DATA_DIRS/lightdm/greeters:$XDG_DATA_DIRS/xgreeters
#backup-logs=true
#dbus-service=true

#
# Seat configuration
#
# Seat configuration is matched against the seat name glob in the section, for example:
# [Seat:*] matches all seats and is applied first.
# [Seat:seat0] matches the seat named "seat0".
# [Seat:seat-thin-client*] matches all seats that have names that start with "seat-thin-client".
#
# type = Seat type (local, xremote)
# pam-service = PAM service to use for login
# pam-autologin-service = PAM service to use for autologin
# pam-greeter-service = PAM service to use for greeters
# xserver-command = X server command to run (can also contain arguments e.g. X -special-option)
# xmir-command = Xmir server command to run (can also contain arguments e.g. Xmir -special-option)
# xserver-config = Config file to pass to X server
# xserver-layout = Layout to pass to X server
# xserver-allow-tcp = True if TCP/IP connections are allowed to this X server
# xserver-share = True if the X server is shared for both greeter and session
# xserver-hostname = Hostname of X server (only for type=xremote)
# xserver-display-number = Display number of X server (only for type=xremote)
# xdmcp-manager = XDMCP manager to connect to (implies xserver-allow-tcp=true)
# xdmcp-port = XDMCP UDP/IP port to communicate on
# xdmcp-key = Authentication key to use for XDM-AUTHENTICATION-1 (stored in keys.conf)
# greeter-session = Session to load for greeter
# greeter-hide-users = True to hide the user list
# greeter-allow-guest = True if the greeter should show a guest login option
# greeter-show-manual-login = True if the greeter should offer a manual login option
# greeter-show-remote-login = True if the greeter should offer a remote login option
# user-session = Session to load for users
# allow-user-switching = True if allowed to switch users
# allow-guest = True if guest login is allowed
# guest-session = Session to load for guests (overrides user-session)
# session-wrapper = Wrapper script to run session with
# greeter-wrapper = Wrapper script to run greeter with
# guest-wrapper = Wrapper script to run guest sessions with
# display-setup-script = Script to run when starting a greeter session (runs as root)
# display-stopped-script = Script to run after stopping the display server (runs as root)
# greeter-setup-script = Script to run when starting a greeter (runs as root)
# session-setup-script = Script to run when starting a user session (runs as root)
# session-cleanup-script = Script to run when quitting a user session (runs as root)
# autologin-guest = True to log in as guest by default
# autologin-user = User to log in with by default (overrides autologin-guest)
# autologin-user-timeout = Number of seconds to wait before loading default user
# autologin-session = Session to load for automatic login (overrides user-session)
# autologin-in-background = True if autologin session should not be immediately activated
# exit-on-failure = True if the daemon should exit if this seat fails
#
[Seat:*]
#type=local
#pam-service=lightdm
#pam-autologin-service=lightdm-autologin
#pam-greeter-service=lightdm-greeter
#xserver-command=X
#xmir-command=Xmir
#xserver-config=
#xserver-layout=
#xserver-allow-tcp=false
#xserver-share=true
#xserver-hostname=
#xserver-display-number=
#xdmcp-manager=
#xdmcp-port=177
#xdmcp-key=
#greeter-session=example-gtk-gnome
#greeter-hide-users=false
#greeter-allow-guest=true
#greeter-show-manual-login=false
#greeter-show-remote-login=true
#user-session=default
#allow-user-switching=true
#allow-guest=true
#guest-session=
session-wrapper=/etc/lightdm/Xsession
#greeter-wrapper=
#guest-wrapper=
#display-setup-script=
#display-stopped-script=
#greeter-setup-script=
#session-setup-script=
#session-cleanup-script=
#autologin-guest=false
#autologin-user=
#autologin-user-timeout=0
#autologin-in-background=false
#autologin-session=
#exit-on-failure=false

#
# XDMCP Server configuration
#
# enabled = True if XDMCP connections should be allowed
# port = UDP/IP port to listen for connections on
# listen-address = Host/address to listen for XDMCP connections (use all addresses if not present)
# key = Authentication key to use for XDM-AUTHENTICATION-1 or blank to not use authentication (stored in keys.conf)
# hostname = Hostname to report to XDMCP clients (defaults to system hostname if unset)
#
# The authentication key is a 56 bit DES key specified in hex as 0xnnnnnnnnnnnnnn.  Alternatively
# it can be a word and the first 7 characters are used as the key.
#
[XDMCPServer]
#enabled=false
#port=177
#listen-address=
#key=
#hostname=

#
# VNC Server configuration
#
# enabled = True if VNC connections should be allowed
# command = Command to run Xvnc server with
# port = TCP/IP port to listen for connections on
# listen-address = Host/address to listen for VNC connections (use all addresses if not present)
# width = Width of display to use
# height = Height of display to use
# depth = Color depth of display to use
#
[VNCServer]
#enabled=false
#command=Xvnc
#port=5900
#listen-address=
#width=1024
#height=768
#depth=8

loqs · 2021-08-28 11:04:54

Try commenting again in the General configuration section

logind-check-graphical = True to on start seats that are marked as graphical by logind

instead uncomment in the [LightDM] section

logind-check-graphical=true

jones · 2021-08-28 11:07:04

Not only did a boot with the i915 KMS produce an ugly looking TTY look at the very beginning of the boot, it also did not change anything.

$ systemctl status lightdm.service 
× lightdm.service - Light Display Manager
     Loaded: loaded (/usr/lib/systemd/system/lightdm.service; enabled; vendor preset: disabled)
     Active: failed (Result: exit-code) since Sat 2021-08-28 13:03:05 CEST; 1min 57s ago
       Docs: man:lightdm(1)
    Process: 1066 ExecStart=/usr/bin/lightdm (code=exited, status=1/FAILURE)
   Main PID: 1066 (code=exited, status=1/FAILURE)
        CPU: 29ms

Aug 28 13:03:05 ArchLinuxT480s systemd[1]: lightdm.service: Scheduled restart job, restart counter >
Aug 28 13:03:05 ArchLinuxT480s systemd[1]: Stopped Light Display Manager.
Aug 28 13:03:05 ArchLinuxT480s systemd[1]: lightdm.service: Start request repeated too quickly.
Aug 28 13:03:05 ArchLinuxT480s systemd[1]: lightdm.service: Failed with result 'exit-code'.
Aug 28 13:03:05 ArchLinuxT480s systemd[1]: Failed to start Light Display Manager.

About the weird look:
- wrong font, then font looked ok
- but during the passphrase prompt for the encrypted system the text only spanned like a third of the screen, then there was a line break

jones · 2021-08-28 11:10:57

loqs wrote:

Try commenting again in the General configuration section
logind-check-graphical = True to on start seats that are marked as graphical by logind
instead uncomment in the [LightDM] section
logind-check-graphical=true

That was it.

D'oh.

=> SOLVED

Thank you very much for your help, loqs.

Arch Linux

#1 2021-08-27 10:54:10

[SOLVED] Lightdm won't start and exits

#2 2021-08-27 11:13:19

Re: [SOLVED] Lightdm won't start and exits

#3 2021-08-27 20:57:40

Re: [SOLVED] Lightdm won't start and exits

#4 2021-08-27 21:49:34

Re: [SOLVED] Lightdm won't start and exits

#5 2021-08-27 22:03:20

Re: [SOLVED] Lightdm won't start and exits

#6 2021-08-27 22:08:29

Re: [SOLVED] Lightdm won't start and exits

#7 2021-08-28 09:03:46

Re: [SOLVED] Lightdm won't start and exits

#8 2021-08-28 09:38:51

Re: [SOLVED] Lightdm won't start and exits

#9 2021-08-28 10:36:26

Re: [SOLVED] Lightdm won't start and exits

#10 2021-08-28 10:50:01

Re: [SOLVED] Lightdm won't start and exits

#11 2021-08-28 10:53:10

Re: [SOLVED] Lightdm won't start and exits

#12 2021-08-28 11:04:54

Re: [SOLVED] Lightdm won't start and exits

#13 2021-08-28 11:07:04

Re: [SOLVED] Lightdm won't start and exits

#14 2021-08-28 11:10:57

Re: [SOLVED] Lightdm won't start and exits

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