Running xubuntu 18.04 LTS the boot animation does not work anylonger (instead I see a black screen) and it takes very long to boot. I changed
/etc/default/grub the line
#GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to
#GRUB_CMDLINE_LINUX_DEFAULT="" and after a
sudo update-grub I do see boot messages on the screen. At a certain point presumably X server or lightdm is starting and the screen blacks out as before. After 2-3 minutes the login screen appears normally.
I don't know what caused this problem, bug I think some update or configuration change by me, but I don't remember anything relevant. I've tried the properitary Nvidia driver and the default one. I use two monitors.
/var/log/lightdm/lightdm.log shows a huge gab of >2min between two lines:
... [+0.94s] DEBUG: Session pid=1104: Authentication complete with return value 0: Success [+0.94s] DEBUG: Seat seat0: Session authenticated, running command [+0.94s] DEBUG: Launching process 1107: xubuntu-numlockx [+1.03s] DEBUG: Process 1107 exited with return value 0 [+1.03s] DEBUG: Seat seat0: Exit status of xubuntu-numlockx: 0 [+1.03s] DEBUG: Session pid=1104: Running command /usr/lib/lightdm/lightdm-greeter-session /usr/sbin/lightdm-gtk-greeter [+1.03s] DEBUG: Creating shared data directory /var/lib/lightdm-data/lightdm [+1.03s] DEBUG: Session pid=1104: Logging to /var/log/lightdm/seat0-greeter.log [+130.54s] DEBUG: Activating VT 7 [+130.54s] DEBUG: Activating login1 session c1 [+130.54s] DEBUG: Seat seat0 changes active session to c1 [+130.54s] DEBUG: Session c1 is already active [+130.81s] DEBUG: Greeter connected version=1.26.0 api=1 resettable=false [+131.18s] DEBUG: Greeter start authentication for peter [+131.18s] DEBUG: Session pid=1585: Started with service 'lightdm', use ...
allow-debugging = true to
/etc/lightdm/lightdm-gtk-greeter.conf which adds some debug messages to
/var/log/lightdm/seat0-greeter.log but AFAICS the messages start after the mysterious two minute sleep.
I couldn't figure out what happens between those two lines. Any idea how I could debug this further?
Edit: the problems disappeared, I don't know how.