Ubuntu – How to unlock locked session

lock

I'm using xubuntu 14.04 on AMD based hardware. It is configured not to lock a session and not to power down automatically on longer idle times.

There have been no recent changes or new software installations other than notified security updates.

I also have the kde desktop installed. The display manager is LightDM, AFAIK.

The system has been behaving nicely for some months, until a couple of days ago. Now, after about ten minutes idle the session is locked automatically. The screen presents a dialog with the caption "This session is locked".

Attempting to "unlock" with the session's username and password results with the message

"You'll be redirected to the unlock dialog in a few seconds" and the cycle starts over. Unable to log in, the only option seems to be to reboot. (I won't mention the work I have just lost":-( )

Does anyone have any idea what's going on here, bearing in mind that AFAIK the power managers are configured NOT to lock sessions and not to power down on idle?

Thanks

Best Answer

I do not have the answer to your bug, actually I experience the same thing, but 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 typing loginctl list-sessions.

If it doesn't work with the first ID, try with the other session IDs of your user account.

Related Solutions

Ubuntu – Lock and Unlock from USB disk (pendrive)

I know it's a terribly late answer, just thought it might help future readers. I posted the answer at Locking with USB drive

Well, a module called PAM (Pluggable Authentication module) can be customized to achieve your need. A beautiful article is available on linuxconfig describing this in detail.

The steps are:

Install PAM

$ sudo apt-get install pamusb-tools libpam-usb

Add USB device to PAM config

$ sudo pamusb-conf --add-device <my-usb-stick>

Select your volume and "Y" to save

Define user for PAM auth

$ sudo pamusb-conf --add-user <ubuntu-user>

Select and "Y" to save
Configure PAM
```
$ sudo gedit /etc/pam.d/common-auth
```
Add the line below and save
```
auth    sufficient      pam_usb.so
```
Test the PAM auth
```
$ su ubuntu-user
```
Lock when disconnected
```
$ sudo gedit /etc/pamusb.conf
```

Modify the block "user" block to look like:

<user id="ubuntu-user"> 
      <device> 
              my-usb-stick 
      </device> 
      <agent event="lock">gnome-screensaver-command -l</agent> 
      <agent event="unlock">gnome-screensaver-command -d</agent> 
 </user>*

Ubuntu – How to unlock file, locked by a process

Try lockf.

lockf - apply, test or remove a POSIX lock on an open file

The lockf() function allows sections of a file to be locked with advisory-mode locks. Calls to lockf() from other processes which attempt to lock the locked file section will either return an error value or block until the section becomes unlocked. All the locks for a process are removed when the process terminates. Record locking with lockf() is supported for regular files.^IBM

Best Answer

Related Solutions

Ubuntu – Lock and Unlock from USB disk (pendrive)

Ubuntu – How to unlock file, locked by a process

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