Display manager does not start at startup

Running sudo start lightdm from the command line seems to work fine though. Neither exec xdm or xdm or sudo xdm or sudo exec xdm do though.

Things I have already tried -

selecting various options from sudo dpkg-reconfigure xdm - whatever option I choose, the problem remains
Checking /etc/X11/default-display-manager contains an absolute path, and that this is the real location of the display manager - /etc/X11/default-display-manager contains /usr/bin/xdm and file /usr/bin/xdm gives ELF 32-bit LSB shared object, Intel 80386, version 1 (SYSV)... which sounds right

Also, /var/log/dmesg contains lots of suspicious entries like

[   21.997255] systemd-udevd[1005]: failed to execute '/lib/udev/socket:@
/org/freedesktop/hal/udev_event' 'socket:@/
org/freedesktop/hal/udev_event': No such file or directory

but I'm not sure what this means or even if it is relevant. Certainly, file /lib/udev/socket gives /lib/udev/socket: ERROR: cannot open `/lib/udev/socket' (No such file or directory) and ls /lib/udev/ | grep socket gives pcmcia-socket-startup. locate udev_event and locate socket | grep socket$ gives this -

/etc/systemd/system/sockets.target.wants/avahi-daemon.socket
/etc/systemd/system/sockets.target.wants/gpsd.socket
/lib/systemd/system/avahi-daemon.socket
/lib/systemd/system/dbus.socket
/lib/systemd/system/gpsd.socket
/lib/systemd/system/systemd-udevd-control.socket
/lib/systemd/system/systemd-udevd-kernel.socket
/lib/systemd/system/dbus.target.wants/dbus.socket
/lib/systemd/system/sockets.target.wants/dbus.socket
/lib/systemd/system/sockets.target.wants/systemd-udevd-control.socket
/lib/systemd/system/sockets.target.wants/systemd-udevd-kernel.socket
/usr/lib/cups/backend/socket
/usr/lib/cups/backend-available/socket
/usr/share/maven-repo/org/eclipse/jetty/jetty-websocket
/usr/share/maven-repo/org/eclipse/jetty/aggregate/jetty-websocket
/var/lib/systemd/deb-systemd-helper-enabled/sockets.target.wants/avahi-daemon.socket
/var/lib/systemd/deb-systemd-helper-enabled/sockets.target.wants/gpsd.socket

and locate udev_event returns no result.

user286997

Posted 2014-01-05T17:34:57.023

Reputation: 1

Answers

Since you're using debian/ubuntu, check the existence of /etc/init.d/xdm and /etc/rc2.d/xdm, whereas the latter should be a symlink to the former. If the latter doesn't exist, you can make one, or use the rcconf tool to create one.

P.S. Sorry I've never heard lightdm, but the package xdm itself should be working fine. And I don't think there's anything to do with the dmesg information.

wangguoqin1001

Posted 2014-01-05T17:34:57.023

Reputation: 164

-1

It's a systemd problem. Apparently most display managers are incompatible with systemd as they use PAM recursively. just google login manager and systemd funkmuscle

deggsy

Posted 2014-01-05T17:34:57.023

Reputation: 1

This does not provide an answer to the question. To critique or request clarification from an author, leave a comment below their post - you can always comment on your own posts, and once you have sufficient reputation you will be able to comment on any post. There are also significant other problems with this answer. There is nothing to salvage with this answer honestly, numerous instances of "systemd" instead of "system", but in the end it doesn't actually answer the question.

– Ramhound – 2015-07-10T12:53:34.563