Lightdm hangs on start?

[HiRez_L]

About a year ago, my system started booting to terminal instead of gui. If I did a ps -ef|grep lightdm, I see it running, but I don't get gui mode until I enter: 'sudo service lightdm restart' . After that, it works fine. I am tring to determine why lightdm is hanging on startup. I have reinstalled lightdm, no change.


System: Dell Optiplex 320 (Don't laugh)
CPU: Single physical core, 2 logical core Pentium 4 3.2GHz
GPU: NVidia GT520, 2 monitors attached
OS: Lubuntu 13.04 x86_64
Kernel: 3.8.0.30-generic
RAM: 4gb, 2 2GB sticks, 4GB Swap


Here is my boot line from grub: BOOT_IMAGE=/boot/vmlinuz-3.8.0-30-generic root=UUID=22eead58-1567-457a-b245-2042bafbbe4a ro splash quiet 5

Where would I start to look to diagnose the problem?

dmesg|grep -i lightdm gets this:

rfelty@REZ:~$ dmesg|grep -i lightdm
[ 24.302817] type=1400 audit(1399049804.350:8): apparmor="STATUS" operation="profile_load" name="/usr/lib/x86_64-linux-gnu/lightdm-remote-session-freerdp/freerdp-session-wrapper" pid=1336 comm="apparmor_parser"
[ 24.303202] type=1400 audit(1399049804.350:9): apparmor="STATUS" operation="profile_load" name="/usr/lib/x86_64-linux-gnu/lightdm-remote-session-freerdp/freerdp-session-wrapper//chromium_browser" pid=1336 comm="apparmor_parser"
[ 24.303643] type=1400 audit(1399049804.350:10): apparmor="STATUS" operation="profile_load" name="/usr/lib/lightdm/lightdm/lightdm-guest-session-wrapper" pid=1335 comm="apparmor_parser"
[ 24.304062] type=1400 audit(1399049804.354:11): apparmor="STATUS" operation="profile_load" name="/usr/lib/lightdm/lightdm/lightdm-guest-session-wrapper//chromium_browser" pid=1335 comm="apparmor_parser"
[ 24.312319] type=1400 audit(1399049804.362:15): apparmor="STATUS" operation="profile_load" name="/usr/lib/x86_64-linux-gnu/lightdm-remote-session-uccsconfigure/uccsconfigure-session-wrapper" pid=1337 comm="apparmor_parser"
[ 24.312730] type=1400 audit(1399049804.362:16): apparmor="STATUS" operation="profile_load" name="/usr/lib/x86_64-linux-gnu/lightdm-remote-session-uccsconfigure/uccsconfigure-session-wrapper//chromium_browser" pid=1337 comm="apparmor_parser"

I don't see any errors in there.

[HiRez_L]

I wen and rebooted and checked again, ps does not find lightdm when it is booted in a terminal with no gui, so lightdm is not starting at all! Any ideas?

[bapoumba]

Had you changed anything to the LightDM configuration ?

https://wiki.ubuntu.com/LightDM

[ibjsb4]

You can try:

sudo dpkg-reconfigure lightdm

[HiRez_L]

Had you changed anything to the LightDM configuration ?

https://wiki.ubuntu.com/LightDM

I don't think I have, my lightdm.conf contains only three lines:

[SeatDefaults]
user-session=ubuntu
greeter-session=unity-greeter

[HiRez_L]

You can try:

sudo dpkg-reconfigure lightdm

Is this the expected output?

rfelty@REZ:~$ sudo dpkg-reconfigure lightdm
rfelty@REZ:~$

[bapoumba]

Should be normal, meaning exit without error.

Now I had a look the other day, and again today, the only lightdm.conf file I have is very different from yours. Are we talking about the same file ?

locate lightdm.conf
/etc/init/lightdm.conf
/etc/lightdm/lightdm.conf.d
/etc/lightdm/lightdm.conf.d/20-lubuntu.conf
/home/bapoumba/Desktop/lightdm.conf
/home/bapoumba/Desktop/lightdm.conf.gz
/usr/share/doc/lightdm/lightdm.conf.gz
/usr/share/lightdm/lightdm.conf.d
/usr/share/lightdm/lightdm.conf.d/50-greeter-wrapper.conf
/usr/share/lightdm/lightdm.conf.d/50-guest-wrapper.conf
/usr/share/lightdm/lightdm.conf.d/50-xserver-command.conf
/usr/share/lightdm/lightdm.conf.d/60-lightdm-gtk-greeter.conf
/var/lib/dpkg/info/lightdm.conffiles
/var/lib/dpkg/info/lightdm.config

The ones on my /Desktop I added myself.

# LightDM - light Display Manager
#
# The display manager service manages the X servers running on the
# system, providing login and auto-login services
#
# based on gdm upstart script

description	"LightDM Display Manager"
author		"Robert Ancell <robert.ancell@canonical.com>"

start on ((filesystem
           and runlevel [!06]
           and started dbus
           and plymouth-ready)
          or runlevel PREVLEVEL=S)

stop on runlevel [016]

emits login-session-start
emits desktop-session-start
emits desktop-shutdown

script
    if [ -n "$UPSTART_EVENTS" ]
    then
        # Check kernel command-line for inhibitors, unless we are being called
        # manually
        for ARG in $(cat /proc/cmdline); do
            if [ "$ARG" = "text" ]; then
		plymouth quit || : 
                stop
		exit 0
            fi
        done

From the wiki page :

LighDM configuration is governed by the lightdm.conf file, however it's not suppose to be directly edited, instead use:
lightdm-set-defaults
Before you start configuring LighDM create a backup file:
sudo cp /etc/lightdm/lightdm.conf /etc/lightdm/lightdm.conf.old

[HiRez_L]

I was looking at the one under /etc/lightdm:

rfelty@REZ:~$ locate lightdm.conf
/etc/init/lightdm.conf
/etc/lightdm/lightdm.conf
/etc/lightdm/lightdm.conf.d
/etc/lightdm/lightdm.conf.d/10-ubuntu.conf
/etc/lightdm/lightdm.conf.d/20-gnome.conf
/etc/lightdm/lightdm.conf.d/50-greeter-wrapper.conf
/etc/lightdm/lightdm.conf.d/50-guest-wrapper.conf
/etc/lightdm/lightdm.conf.d/50-xserver-command.conf
/usr/share/doc/lightdm/lightdm.conf.gz
/var/lib/dpkg/info/lightdm.conffiles
/var/lib/dpkg/info/lightdm.config

/etc/init/lightdm.conf is this:

# LightDM - light Display Manager
#
# The display manager service manages the X servers running on the
# system, providing login and auto-login services
#
# based on gdm upstart script


description     "LightDM Display Manager"
author          "Robert Ancell <robert.ancell@canonical.com>"


start on ((filesystem
           and runlevel [!06]
           and started dbus
           and plymouth-ready)
          or runlevel PREVLEVEL=S)


stop on runlevel [016]


emits login-session-start
emits desktop-session-start
emits desktop-shutdown


script
    if [ -n "$UPSTART_EVENTS" ]
    then
        # Check kernel command-line for inhibitors, unless we are being called
        # manually
        for ARG in $(cat /proc/cmdline); do
            if [ "$ARG" = "text" ]; then
                plymouth quit || :
                stop
                exit 0
            fi
        done


        [ ! -f /etc/X11/default-display-manager -o "$(cat /etc/X11/default-display-manager 2>/dev/null)" = "/usr/bin/lightdm" -o "$(cat /etc/X11/default-display-manager 2>/dev/null)" = "/usr/sbin/lightdm" ] || { stop; exit 0; }


        if [ "$RUNLEVEL" = S -o "$RUNLEVEL" = 1 ]
        then
            # Single-user mode
            plymouth quit || :
            exit 0
        fi
    fi


    exec lightdm
end script


post-start script
    sleep 5
    clear > /dev/tty7
end script


post-stop script
        if [ "$UPSTART_STOP_EVENTS" = runlevel ]; then
                initctl emit desktop-shutdown
        fi
end script

[bapoumba]

have you edited the file yourself ? Do you have a backup ?

[HiRez_L]

I have not edited it. Could a problem with plymouth be the underlying cause?