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reannual

Member

From: Denmark

Registered: 2013-04-11

Posts: 21

Website

Simultaneous X sessions: 'No screens found' error

I'm trying to get a second X session running in which to run Openbox side-by-side with my main Gnome-centered session.

Most guides I've found are ancient (5-10 years) so it involves a a fair bit of guesswork. However, the gist seems to be to switch to an unused TTY (Ctrl+Alt+Fx), log in and run a variation of 'startx -- :1' and add an 'exec [WindowManager of Choice]' line to .xinitrc . So I've just put in 'exec openbox'.

Running startx this way produces the error message 'No screens found'. Inspecting the log file seems to reveal that the error stems from not being able to load a fitting display driver:

[   680.504] (II) LoadModule: "glx"
[   680.505] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[   680.514] (II) Module glx: vendor="NVIDIA Corporation"
[   680.514]    compiled for 4.0.2, module version = 1.0.0
[   680.514]    Module class: X.Org Server Extension
[   680.514] (II) NVIDIA GLX Module  343.36  Mon Dec  1 15:50:02 PST 2014
[   680.514] (==) Matched nouveau as autoconfigured driver 0
[   680.514] (==) Matched nv as autoconfigured driver 1
[   680.514] (==) Matched modesetting as autoconfigured driver 2
[   680.514] (==) Matched fbdev as autoconfigured driver 3
[   680.514] (==) Matched vesa as autoconfigured driver 4
[   680.514] (==) Assigned the driver to the xf86ConfigLayout
[   680.514] (II) LoadModule: "nouveau"
[   680.515] (WW) Warning, couldn't open module nouveau
[   680.515] (II) UnloadModule: "nouveau"
[   680.515] (II) Unloading nouveau
[   680.515] (EE) Failed to load module "nouveau" (module does not exist, 0)
[   680.515] (II) LoadModule: "nv"
[   680.515] (WW) Warning, couldn't open module nv
[   680.515] (II) UnloadModule: "nv"
[   680.515] (II) Unloading nv
[   680.515] (EE) Failed to load module "nv" (module does not exist, 0)
[   680.515] (II) LoadModule: "modesetting"
[   680.515] (WW) Warning, couldn't open module modesetting
[   680.515] (II) UnloadModule: "modesetting"
[   680.515] (II) Unloading modesetting
[   680.515] (EE) Failed to load module "modesetting" (module does not exist, 0)
[   680.515] (II) LoadModule: "fbdev"
[   680.515] (WW) Warning, couldn't open module fbdev
[   680.515] (II) UnloadModule: "fbdev"
[   680.515] (II) Unloading fbdev
[   680.515] (EE) Failed to load module "fbdev" (module does not exist, 0)
[   680.515] (II) LoadModule: "vesa"
[   680.516] (WW) Warning, couldn't open module vesa
[   680.516] (II) UnloadModule: "vesa"
[   680.516] (II) Unloading vesa
[   680.516] (EE) Failed to load module "vesa" (module does not exist, 0)
[   680.516] (EE) No drivers available.
[   680.516] (EE)
Fatal server error:
[   680.516] (EE) no screens found(EE)

Now I have the proprietary Nvidia driver installed from the nvidia package in extra and it is automatically picked up and used in my ordinary X session (the only configuration in /et/X11/xorg.conf.d/ is a DisplayClass setting for my keyboard).

However, to test the idea that this was indeed what was halting operations, I noticed that it also tried to pick up the vesa driver (on what appears to be the end of a prioritized list). So I tried installing xf86-video-vesa and running the startx command again. This time I did not get the error message and the log produces a much more complete impression of an X session. The screen however is just turned into black and white noise.

So my main question is: Assuming that module 'nv' is the proprietary Nvidia driver why can't my new X session open that?

And secondarily: Supposing that I can get X to use a working driver is this approach likely to work?

karol

Archivist

Registered: 2009-05-06

Posts: 25,440

Re: Simultaneous X sessions: 'No screens found' error

What do you mean 'ancient guides'? And the Arch wiki?
The wiki will tell you how to pick the correct driver for your card and 'nv' is not 'nvidia'.

I use 'startx -- -keeptty' to start every X instance.
Post the .xinirtc you're using for the second session.

Head_on_a_Stick

Member

From: The Wirral

Registered: 2014-02-20

Posts: 9,003

Website

Re: Simultaneous X sessions: 'No screens found' error

Put this in your ~/.bash_profile:

[[ -z $DISPLAY && $XDG_VTNR -eq 2 ]] && exec startx

This will run your openbox .xinitrc when you log into TTY2 -- GDM doesn't parse .xinitrc at all so there is no conflict.

You should create the .xinitrc by copying the sample from /etc/skel & modifying to your needs.
https://wiki.archlinux.org/index.php/Xinitrc

This works in my system (Intel HD4600, GDM running on TTY1), I have no idea about your module-related errors though.

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Jin, Jîyan, Azadî