With XUbuntu 18.10 (pretty fresh install) when locking the system the monitor is immediately suspended; pressing any key or mouse button doesn't wake it. Pressing CTRL + ALT + F7 finally wakes the monitor and the message below is presented:
This session is locked
You'll be redirected to the unlock
dialog automatically in a few seconds
then the lock screen appears and everything goes as expected.
Another solution is to type the password (while the monitor is still blank) then press ENTER which then wakes the monitor and also unlocks the session (if the password is correctly typed, of course).
I have these settings (Display Power Management on or off and/or Automatically lock the session activated or not make no difference):
The expected behavior with Display Power Management on and Automatically lock the session activated is:
- when locking the system first the monitor should be still on
- the lock window should be presented
- after 10 min the monitor should go black
- after 15 min the monitor should sleep
- after 60 min the monitor should switch off
- when pressing any key or mouse the monitor should switch on and the lock window be presented
What should I do in order to obtain the desired behavior? also I don't want to avoid the problem by using xscreensaver
UPDATE
The same behavior is no matter what I choose for Display Power Management and/or Automatically lock the session.
With Power Manager unchecked in Session and Startup (Screen Locker still checked) the behavior is the same. I guess it's a Screen Locker (light-locker) issue.
This is the /var/log/syslog created when locking:
Apr 12 20:24:26 adrhc systemd[1]: Started /run/user/111 mount wrapper.
Apr 12 20:24:26 adrhc systemd[1]: Created slice User Slice of UID 111.
Apr 12 20:24:26 adrhc systemd[1]: Starting User Manager for UID 111...
Apr 12 20:24:26 adrhc systemd[1]: Started Session c9 of user lightdm.
Apr 12 20:24:26 adrhc systemd[21272]: Reached target Paths.
Apr 12 20:24:26 adrhc systemd[21272]: Listening on GnuPG network certificate management daemon.
Apr 12 20:24:26 adrhc systemd[21272]: Starting D-Bus User Message Bus Socket.
Apr 12 20:24:26 adrhc systemd[21272]: Listening on GnuPG cryptographic agent and passphrase cache.
Apr 12 20:24:26 adrhc systemd[21272]: Listening on GnuPG cryptographic agent (ssh-agent emulation).
Apr 12 20:24:26 adrhc systemd[21272]: Listening on GnuPG cryptographic agent and passphrase cache (access for web browsers).
Apr 12 20:24:26 adrhc systemd[21272]: Listening on GnuPG cryptographic agent and passphrase cache (restricted).
Apr 12 20:24:26 adrhc systemd[21272]: Listening on Sound System.
Apr 12 20:24:26 adrhc systemd[21272]: Reached target Timers.
Apr 12 20:24:26 adrhc systemd[21272]: Listening on D-Bus User Message Bus Socket.
Apr 12 20:24:26 adrhc systemd[21272]: Reached target Sockets.
Apr 12 20:24:26 adrhc systemd[21272]: Reached target Basic System.
Apr 12 20:24:26 adrhc systemd[21272]: Reached target Default.
Apr 12 20:24:26 adrhc systemd[21272]: Startup finished in 33ms.
Apr 12 20:24:26 adrhc systemd[1]: Started User Manager for UID 111.
Apr 12 20:24:26 adrhc systemd[21272]: Started D-Bus User Message Bus.
Apr 12 20:24:26 adrhc dbus-daemon[21342]: [session uid=111 pid=21342] AppArmor D-Bus mediation is enabled
Apr 12 20:24:26 adrhc dbus-daemon[21342]: [session uid=111 pid=21342] Activating via systemd: service name='org.a11y.Bus' unit='at-spi-dbus-bus.service' requested by ':1.1' (uid=111 pid=21337 comm="/usr/sbin/lightdm-gtk-greeter " label="unconfined")
Apr 12 20:24:26 adrhc systemd[21272]: Starting Accessibility services bus...
Apr 12 20:24:26 adrhc dbus-daemon[21342]: [session uid=111 pid=21342] Successfully activated service 'org.a11y.Bus'
Apr 12 20:24:26 adrhc systemd[21272]: Started Accessibility services bus.
Apr 12 20:24:26 adrhc at-spi-bus-launcher[21343]: dbus-daemon[21348]: Activating service name='org.a11y.atspi.Registry' requested by ':1.0' (uid=111 pid=21337 comm="/usr/sbin/lightdm-gtk-greeter " label="unconfined")
Apr 12 20:24:26 adrhc dbus-daemon[21342]: [session uid=111 pid=21342] Activating via systemd: service name='org.gtk.vfs.Daemon' unit='gvfs-daemon.service' requested by ':1.3' (uid=111 pid=21337 comm="/usr/sbin/lightdm-gtk-greeter " label="unconfined")
Apr 12 20:24:26 adrhc at-spi-bus-launcher[21343]: dbus-daemon[21348]: Successfully activated service 'org.a11y.atspi.Registry'
Apr 12 20:24:26 adrhc at-spi-bus-launcher[21343]: SpiRegistry daemon is running with well-known name - org.a11y.atspi.Registry
Apr 12 20:24:26 adrhc systemd[21272]: Starting Virtual filesystem service...
Apr 12 20:24:26 adrhc dbus-daemon[21342]: [session uid=111 pid=21342] Successfully activated service 'org.gtk.vfs.Daemon'
Apr 12 20:24:26 adrhc systemd[21272]: Started Virtual filesystem service.
Apr 12 20:24:57 adrhc systemd[1]: session-c9.scope: Killing process 21244 (lightdm) with signal SIGTERM.
Apr 12 20:24:57 adrhc systemd[1]: session-c9.scope: Killing process 21327 (gnome-keyring-d) with signal SIGTERM.
Apr 12 20:24:57 adrhc systemd[1]: session-c9.scope: Killing process 21336 (lightdm-greeter) with signal SIGTERM.
Apr 12 20:24:57 adrhc systemd[1]: session-c9.scope: Killing process 21337 (lightdm-gtk-gre) with signal SIGTERM.
Apr 12 20:24:57 adrhc systemd[1]: Stopping Session c9 of user lightdm.
Apr 12 20:24:57 adrhc systemd[1]: Stopped Session c9 of user lightdm.
Apr 12 20:24:57 adrhc systemd[1]: user-runtime-dir@111.service: Unit not needed anymore. Stopping.
Apr 12 20:24:57 adrhc systemd[1]: Stopping User Manager for UID 111...
Apr 12 20:24:57 adrhc systemd[21272]: Stopped target Default.
Apr 12 20:24:57 adrhc gvfsd[21352]: A connection to the bus can't be made
Apr 12 20:24:57 adrhc systemd[21272]: Stopping Accessibility services bus...
Apr 12 20:24:57 adrhc systemd[21272]: Stopping D-Bus User Message Bus...
Apr 12 20:24:57 adrhc systemd[21272]: Stopping Virtual filesystem service...
Apr 12 20:24:57 adrhc systemd[21272]: Stopped D-Bus User Message Bus.
Apr 12 20:24:57 adrhc systemd[21272]: Stopped Accessibility services bus.
Apr 12 20:24:57 adrhc systemd[21272]: Stopped Virtual filesystem service.
Apr 12 20:24:57 adrhc systemd[21272]: Stopped target Basic System.
Apr 12 20:24:57 adrhc systemd[21272]: Stopped target Paths.
Apr 12 20:24:57 adrhc systemd[21272]: Stopped target Timers.
Apr 12 20:24:57 adrhc systemd[21272]: Stopped target Sockets.
Apr 12 20:24:57 adrhc systemd[21272]: Closed GnuPG cryptographic agent and passphrase cache (access for web browsers).
Apr 12 20:24:57 adrhc systemd[21272]: Closed GnuPG cryptographic agent and passphrase cache.
Apr 12 20:24:57 adrhc systemd[21272]: Closed Sound System.
Apr 12 20:24:57 adrhc systemd[21272]: Closed GnuPG network certificate management daemon.
Apr 12 20:24:57 adrhc systemd[21272]: Closed GnuPG cryptographic agent and passphrase cache (restricted).
Apr 12 20:24:57 adrhc systemd[21272]: Closed GnuPG cryptographic agent (ssh-agent emulation).
Apr 12 20:24:57 adrhc systemd[21272]: Closed D-Bus User Message Bus Socket.
Apr 12 20:24:57 adrhc systemd[21272]: Reached target Shutdown.
Apr 12 20:24:57 adrhc systemd[21272]: Starting Exit the Session...
Apr 12 20:24:57 adrhc systemd[1]: user-runtime-dir@111.service: Unit not needed anymore. Stopping.
Apr 12 20:24:57 adrhc systemd[1]: Stopped User Manager for UID 111.
Apr 12 20:24:57 adrhc systemd[1]: user-runtime-dir@111.service: Unit not needed anymore. Stopping.
Apr 12 20:24:57 adrhc systemd[1]: Stopping /run/user/111 mount wrapper...
Apr 12 20:24:57 adrhc systemd[1]: Removed slice User Slice of UID 111.
Apr 12 20:24:57 adrhc systemd[1]: Stopped /run/user/111 mount wrapper.
Best Answer
I do not have the actual solution of your problem yet but a temporary solution.
I found here a way to recover the situation without reboot the machine/LightDM.
In your tty1 Ctrl+Alt+F1, as root, type
loginctl unlock-session [id], where[id]is the session id you get by runningloginctl list-sessions.If it doesn't work with the first ID, try with the other session IDs of your user account.
Try this as well.