lightdm on Xephyr main display

abc12345 · 2022-09-21 09:07:23

I am running Xephyr as my main display on top of Xorg display server. I do not know how to run lightdm (assuming it's the simplest DM) with this setup. I found one post where it involves a lot of nontrivial setup. How do I do it?

seth · 2022-09-21 14:54:39

I found one post where it involves a lot of nontrivial setup. How do I do it?

Do what? The non-trivial setup? If you found a post that explains the process, what are you asking for?
Otherwise you'll have to alter the "xserver-command" in lightdm.conf and/or an alternative config file if you want to use lightdm for the main server as well.

abc12345 · 2022-09-21 15:42:28

I'm just thoroughly confused.

seth · 2022-09-21 19:06:48

Maybe stay away from the wall outlet.

It's not clear what drives your confusion - but since the idea to run lightdm in a xephyr server (outside testing purposes), let alone "running Xephyr as my main display on top of Xorg display server" is kinda weird, maybe explain what you want to achieve, what you've tried and where you're stuck.

Right now this thread is borderline "I want to do thing and i found a way to do thing, how do I do thing?" - and I don't mean "thing" as a placeholder here.

abc12345 · 2022-09-22 06:08:20

Why is `running Xephyr as my main display on top of Xorg display server` kinda weird? That is what ArchWiki says to do, nothing weird about it.
I don't know how much clearer I could've been in what I wanted to do and where I got stuck.
There's a security reason to run Xephyr as your main display on top of Xorg, so it's natural to want to make other things work in this setup, like getting any DM to work so you can lock up your screen.

seth · 2022-09-22 07:11:41

You haven't even attempted to explain *anything*.

Read https://bbs.archlinux.org/viewtopic.php?id=57855

Then maybe start by pointing to the segment in the wiki that you belive to tell you to use xephyr as "main display on top of Xorg display server" - xephyr is a nested X11 server, it's by its very nature not "main", but the wiki will at least hint us what you're trying to achieve there.

Then explain how you're currently trying to run lightdm on xephyr (at least link the post you referenced before) and finally how you've attempted to run lightdm on Xephyr, whether that included the "xserver-command" in lightdm.conf and what the results were.

There's a security reason to run Xephyr as your main display on top of Xorg

No?
But I'm curious to hear what kind of security you think you can achieve this way.

getting any DM to work so you can lock up your screen

These things are entirely *not* related (you do not only need a DM, the DM is not involved in locking your screen either - at least not in it's DM capacity. lightdm can lock your screen *as well*, but it's *not* the login related stuff that's doing that)
And i3lock, slock, xscreensaver, … all lock your screen fine, regardless of any DM.

abc12345 · 2022-09-22 07:11:44

I'm getting some errors when I try to test lightdm. It's similar to this problem but it's not the same culprit: https://bbs.archlinux.org/viewtopic.php?id=236839
I followed https://wiki.archlinux.org/title/LightDM#Testing and I get this error running as a regular user:

lightdm --test-mode --debug
[+0.00s] DEBUG: Logging to /home/user/.cache/lightdm/log/lightdm.log
[+0.00s] DEBUG: Starting Light Display Manager 1.32.0, UID=1000 PID=55355
[+0.00s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /usr/local/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /etc/xdg/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration from /etc/lightdm/lightdm.conf
[+0.00s] DEBUG: Running in user mode
[+0.00s] DEBUG: Using Xephyr for X servers
[+0.00s] DEBUG: Registered seat module local
[+0.00s] DEBUG: Registered seat module xremote
[+0.00s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager
[+0.00s] DEBUG: _g_io_module_get_default: Found default implementation local (GLocalVfs) for ?gio-vfs?
[+0.00s] DEBUG: Monitoring logind for seats
[+0.00s] WARNING: Could not enumerate user data directory /var/lib/lightdm-data: Error opening directory '/var/lib/lightdm-data': Permission denied
[+0.00s] DEBUG: Acquired bus name org.freedesktop.DisplayManager
[+0.00s] DEBUG: Could not run plymouth --ping: Failed to execute child process ?plymouth? (No such file or directory)

/var/lib/lightdm-data is 0770

Arch Linux

#1 2022-09-21 09:07:23

lightdm on Xephyr main display

#2 2022-09-21 14:54:39

Re: lightdm on Xephyr main display

#3 2022-09-21 15:42:28

Re: lightdm on Xephyr main display

#4 2022-09-21 19:06:48

Re: lightdm on Xephyr main display

#5 2022-09-22 06:08:20

Re: lightdm on Xephyr main display

#6 2022-09-22 07:11:41

Re: lightdm on Xephyr main display

#7 2022-09-22 07:11:44

Re: lightdm on Xephyr main display

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