DEFAULT_WM="xfce" yet still KDE Plasma loads?

English Install/Boot/Login
1

I have updated one computer from Leap 42.3 to Leap 15.0
While on 42.3 it always had auto login for XFCE and it workes fine.

However after updating it attempts to boot into KDE Plasma and hangs at that. The only way out is hardware reset. Or to avoid reaching the point when that is needed, while KDE Plasma tries to load I press Alt+Ctrl+F1 and after some waiting back Alt+F7 - then a login prompt is displayed but strangely, still Plasma is selected in the dropdown.

Regardless of how many times I login/logout explicitly selecting XFCE and reboot - nothing changes.

I have:


$ grep 'DISPLAYMANAGER=' /etc/sysconfig/displaymanager
DISPLAYMANAGER="lightdm"
$ grep 'DEFAULT_WM=' /etc/sysconfig/windowmanager
DEFAULT_WM="xfce"
$ cat ~/.dmrc 
[Desktop]
Session=xfce

*FWIW: using nouveau

What might the be causing all this?

2
  1. Disable auto-login (Can be set in YaST > /etc/sysconfig editor > Desktop > Display manager > DISPLAYMANAGER_AUTOLOGIN
  2. On the login screen where you enter username/password, you can select your Desktop there. I haven’t found any other way to select the Desktop reliably.

You can view and change your Window Manager with the following, but what results depends heavily on whether your Window Manager is supported by your chosen Display Manager

update-alternatives --config default-xsession.desktop

Done properly,
You shouldn’t need to back screen or other unusual actions… Everything should move to the next screen naturally.

TSU

3

The people who use that computer want the conveniece of having auto login, so telling them they can’t have it because the software is unreliable sounds bad. I am looking for way to give them what they want (which is what they had for years).

You shouldn’t need to back screen or other unusual actions… Everything should move to the next screen naturally.

What are you talking about?

4

Two options:

  • Make these persons aware that auto_login is a major security issue.
  • Do what Tsu wrote, login on Xfce once, use YaST - System - sysconfigeditor to search for autologin and set it by putting in the username. The session will be remembered, so the next autologin should be in Xfce
5

I have done that but they still prefer the convenience. Plus that’s their home computer, not a publicly accessible machine.

  • Do what Tsu wrote, login on Xfce once, use YaST - System - sysconfigeditor to search for autologin and set it by putting in the username. The session will be remembered, so the next autologin should be in Xfce

Please let me check if I understand correctly:

Before opening this thread I have already visited sysconfigeditor in Yast and the username was there, so no change was required as everything was already set (as it has always been). Are you suggesting that removing the username, then putting it again and confirming would “remember” something more than what is already set in sysconfig? If yes - where exactly is that remembered? Is it not DEFAULT_WM setting which is used to “remember” that? (please consider the info in the OP)

Also - how does all this explain the hanging which I described?

This is all quite confusing, I hope you can clarify.

6

Disable autologin.
Set your Desktop and your desired Window Manager (depends on whatever is offered)
Then disable autoloin.

You’ll be back to an automatic login with the settings you want.

TSU

7

I suppose you mean “then enable”?

You’ll be back to an automatic login with the settings you want.

I will try this tomorrow when I visit that PC. Meanwhile - could you please tell where these settings are saved? Is it not ~/.dmrc which remembers that and which I already have?

8

Your basic problem is that “/etc/sysconfig/displaymanager” is not being used the way it was used in 42.3

Login to whatever desktop you get.
Open a terminal (“konsole” or “xterm”) and “su” to become root. Or open a root terminal from the menu, which I think gives you “konsole”.

update-alternatives --config default-displaymanager

and select “lightdm” as your choice.

Optionally,

update-alternatives --config default-xsession.desktop

and set that to XFCE (maybe it says “xfce” or “xfce-session” or similar). But you are given a list of choices.

I say “optional” because it doesn’t actually matter.

When you have made those choices, reboot.

If you finish up in the wrong desktop environment, then logout. You should get a login screen. From there, you can select your desktop and login. For “lightdm” the desktop selector is an icon near the top right of the screen. You may have to experiment with clicking on icons to see which gives you a desktop choice.

Once you have logged in to your desired desktop, “lightdm” should remember your selection and use that the next time.

9

The update-alternatives way worked. Thanks!

Why is that?
Where are the settings stored in Leap 15.0?

Also - why auto login to KDE Plasma results in hanging of the computer during this auto login but manually logging into Plasma works?

10

As Neil said, it has moved up to update-alternatives.

Now in /etc/alternatives/default-displaymanager which is a symlink to the file in /usr/lib/X11/displaymanagers/

11

It’s mentioned in the release notes for Leap 15.0…

Where are the settings stored in Leap 15.0?

Refer to

man update-alternatives

The generic name is not a direct symbolic link to the selected alternative. Instead, it is a symbolic link to a
name in the alternatives directory, which in turn is a symbolic link to the actual file referenced. This is done
so that the system administrator’s changes can be confined within the /etc directory: the FHS (q.v.) gives reasons
why this is a Good Thing.

12

Thanks you guys!