lightdm lock screen does not work

[srope01]

I have installed Lubuntu 14.04 on an IBM S50 ThinkCentre. When I try to manually lock the screen, for example by going to the shutdown panel button and selecting "Lock Screen", it doesn't do anything. Interestingly, if I go to the terminal and type out the command

dm-tool lock

then the lock screen sort of works. The whole screen goes blank with no password login prompt. If I hit return, then I get the login prompt so I can log back in.

Does anyone have any ideas of what is going wrong?

[bapoumba]

You are not alone, same here. <ctrl><alt><l>, lxlock or Logout Menu > Lock Screen do not work either for me.
https://bugs.launchpad.net/ubuntu/+s...n/+bug/1286686

bapoumba@SonyBlue:~$ light-locker-command
** Message: light-locker is not running
bapoumba@SonyBlue:~$ light-locker &
[1] 5415
bapoumba@SonyBlue:~$ light-locker-command -l
bapoumba@SonyBlue:~$ lxlock

Both last 2 commands work after starting light-locker. This is how far I've got when I looked at after a fresh install, as I like to lock my screen when I walk away..
Got the idea to test this from /usr/bin/lxlock

I'm not sure I'm on the right tracks because this does nothing :

bapoumba@SonyBlue:~$ lxsession-default lock
lock

Launching lock manager

Edit : I should add that leaving the computer unattended does blank out the screen and login is required after waking it up after running light-locker.

[srope01]

Ah ok. So your solution would be a work around. If I start the light-locker process in a rc startup file somewhere, then the Lock Screen button would work. That would be good enough for me until they fix the bug. I will check that out and post it here when I figured it out.

[bapoumba]

I've added it to the Prefs > Default Apps for LXsession > Autostart tab. Not rebooted yet, will see if it works tomorrow.

[srope01]

I just tried your solution and it worked. Thanks! I guess this one is solved (or at least there is a workaround as the bug still has to be fixed).

[bapoumba]

I just tried your solution and it worked. Thanks! I guess this one is solved (or at least there is a workaround as the bug still has to be fixed).

You're welcome
Works for me too. Will add a comment to the bug thread and link back here.

[ale-magnolo]

light-locker gives me the impression to work but I can bypass it by pressing CTRL-ALT-F7
so in my opinion this thread should be marked as NOT SOLVED

[bapoumba]

light-locker gives me the impression to work but I can bypass it by pressing CTRL-ALT-F7
so in my opinion this thread should be marked as NOT SOLVED

That is strange. If I lock the screen and hit <ctrl><alt><F7> I get a message with a lock saying : This session is locked. you'll be directed to the unlock dialog automatically in a few seconds.
Which it does..

What do you have in your light-locker settings ?

[ale-magnolo]

I had the exact same settings as you, except for "lock on suspend" that was off, so I put it on but I still have the same problem of bypassing the lock with CTRL-ALT-F7.

I launch the locker with:
light-locker-command -l

The version I get with the -V param is:
light-locker-command 1.4.0

My system is Lubuntu 14.04 upgraded from a previous install, I think it was 13.10.

[bapoumba]

I had the exact same settings as you, except for "lock on suspend" that was off, so I put it on but I still have the same problem of bypassing the lock with CTRL-ALT-F7.

I launch the locker with:
light-locker-command -l

The version I get with the -V param is:
light-locker-command 1.4.0

My system is Lubuntu 14.04 upgraded from a previous install, I think it was 13.10.

Using light-locker-command -l also works for me, and I have the same version as you :

bapoumba@SonyBlue:~$ light-locker-command -V
light-locker-command 1.4.0

I fresh installed lubuntu 14.04 after having upgraded every release from 12.04.