multiseat config

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

Still isn't solved

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

Definitely not expired...

My config looks like this:

[Seat:0]
xserver-command=/usr/bin/X -config /etc/X11/seat0.conf -layout Seat0

[Seat:1]
xserver-command=/usr/bin/X -config /etc/X11/seat1.conf -layout Seat1 -sharevts -novtswitch

I use separate X configs to get input devices hotplug using udev. You can omit it if you aren't interested in hotplug.
sharevts and novtswitch could be used for the first seat as well, I noticed no difference on my system, but you must have them for second seat.

Also I suggest you to look on KDM if you won't have lightdm working. KDM worked like a charm for me before, but it requires about 90 megs of KDE dependencies. Lightdm is too buggy for multiseat so far imo.

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

Does lightdm work well for you?

What is content of your seat0.conf and seat1.conf ?

Thank you :-)

This case is realy Open !!! Ubuntu lacks one of basic propertyes of
old versions!!!

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

I wouldn't say this is expired.

Please see my branch andrzejtp2010/lightdm-xephyr-multiseat.

This adds support for configuration parameters which enable running a Xephyr-based multiseat solution.

A Xephyr-based multiseat, in short, assumes starting just one X server, which covers all the monitors, and then start a number of Xephyrs nested within it. Each Xephyr takes keyboard and mouse input from kernel's event interface, which allows distinguishing
between the mice and the keyboards. xwininfo and xwmctrl are used to move Xephyrs into their desired positions. You can look for details (although for gdm2-based solution) in here: beforeafterx.blogspot.com.

Xephyr used to support "evdev" pointer and keyboard drivers. In current version of Debian wheezy, it does not, though, or I can't configure it properly. So I run an experimental setup with an old Xephyr binary which does support "evdev".

In my experimental setup I use a custom xserver-command for the Xephyr-based seats.

In my experimental setup I use a custom xinerama.desktop and multiseat-greeter.desktop. The first runs a fake greeter which is just a repeated "sleep" command. The second runs a script, which moves its respective Xephyr window into its desired location and "exec"s the greeter.

If anyone is interested, I will post some more details soon.

OK, this does not work on master branch (yet).

I successfully run it on 1.0.11 sources from Debian wheezy.

Then I ported the changes to current master branch from bazaar. There was a conflict due to some architectural changes related to sessions. I resolved the conflict and commited. And then it was too late at night to try it. Now I tried. I does not work :(

I guess it has something to do with session child stuff: there are more processes so, perhaps, communication between them using signals does not work as expected by design if one of the processes is actually a script. However, in the script I do exec the greeter... What I also suppose is that, perhaps, the daemon now expects some more communication from the greeter, so a fake greeter which in fact does not run any (interesting) program will not send anything over any channel like to/from child file descriptors. Perhaps, perhaps, perhaps...

So, some questions to lightdm developers:

1. Is it possible to use a custom greeter, whose filename is specified in the "Exec" entry in a .desktop file?
2. If yes, then can it be a script?
3. If yes, then does it have to follow some protocol like reading/writing from/to some file descriptors (e.g. specified with environment variables)?

I uploaded a 1.0-based branch, too. This works.

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

active

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

active

I am going to come back to it in July. Meanwhile you can findsome info on configuring the lightdm 1.0 solution on beforeafterx.blogspot.com

Thank you!

Though I don't want to use xephyr, because it is slow. I am looking for an gpu-accelerated solution, like the one that I have now with gdm.

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

aktiv

Sorry for such a late answer. There is nothing special in my Xorg.conf files. As I said before I keep 'em separated to get input hotplug. Check it yourself:
-----------------------------------------------
Section "ServerFlags"
 Option "DontZap" "false"
EndSection

Section "InputClass"
        Identifier "Generic input device"
        MatchTag "seat0"
 Driver "evdev"
EndSection

Section "Monitor"
 Identifier "Samsung"
 Option "DPMS" "true"
EndSection

Section "Device"
 Identifier "GeForce GT 520"
 Driver "nvidia"
 BusID "PCI:1:0:0"
EndSection

Section "Screen"
 Identifier "Left Screen"
 Device "GeForce GT 520"
 Monitor "Samsung"
 DefaultDepth 24
 SubSection "Display"
  Viewport 0 0
  Depth 24
 EndSubSection
EndSection

Section "ServerLayout"
 Identifier "Seat0"
 Screen 0 "Left Screen" 0 0
 Option "SingleCard" "on"
EndSection
-----------------------------------------------

My lightdm configuration changed a bit:
-----------------------------------------------
[Seat:0]
xserver-command=/usr/bin/X -config /etc/X11/seat0.conf -layout Seat0

[Seat:1]
xserver-command=/usr/bin/X -config /etc/X11/seat1.conf -layout Seat1 -sharevts -keeptty
-----------------------------------------------

I added -keeptty to avoid Ctrl+C combination killing xserver sometimes; -novtswitch added automatically by lightdm.

I use two GeForce cards with closed driver. Depending on your hardware it may be impossible to run OpenGL accelerated xservers for both seats, so your problem could be out of scope of lightdm.

Anyway since I updated lightdm 1.0 -> 1.2 I experience very naughty bug: after my system starts only one seat is activated (random one). Logs show that greeter fails to connect to second xserver (though it starts and logs are clear of errors) and lightdm stops trying to do it. Manually restarting lightdm makes everything work fine. I'm confused.

I also experienced that bug when only one seat does up. I wonder if developers of lightdm have any idea about this issue.

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

Still having problems

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

Not solved.

My configuration is:
GNU/Debian testing
lightdm 1.2.2

After many trouble now I have something working.
But I still have two issues:

- like lev-abashkin randomly only one seat is activeted and I have to manually restart lightdm
- after logging out on one seat lightdm doesn't restart the X process if the other seat has X process running. It seems like lightdm checks the presence of X without look on which seat is. Really annoying.

Any suggest?
Do you need more information (conf files)?

Same story here. LightDM doesn't try to restart X after fail or logoff. The worst thing is there is no other display manager today which supports old-way config-based multiseat except KDM (And KDM can't start two xservers on my hardware for some reason.) I wish I had more time to refresh my C memories and dive into this issue, but I have not to my regret.

Hello all,

Some update from me.

I pushed a new andrzejtp2010/lightdm-1.2-xephyr-multiseat branch which contains only 2 out of the 4 patches applied to the 1.0 version. Please read beforeafterx.blogspot.com to learn more.

I tested lightdm-1.2 with Xephyr on a recent Debian Wheezy; I created a custom live distribution with lxde-core and it seems to work. However, ocassionally, one of the seats does not start properly: the X server is started, but the greeter has a problem, plus the X server is not moved (remember this is a Xephyr approach which includes moving nested X servers into proper positions). I am thinking that this could be related to some timing issues, like a script trying to move an X server when the server is not completely running. I don't know.

However, if both seats are started correctly, than this looks fairly stable. Users can log in and out and nothing bad happens.

@Khumarahn: I understand you want GL. Xephyr is good enough for me - I can watch youtube and play DVDs. I remember that I bumped into a project which aims at adding GL support to Xephyr. Ah, here it is: http://gitorious.org/xephyr-with-gl-acceleration. I even cloned a git repo and tried building, no success though. The project unfortunately seems a little dead - the last commit was over two years ago. Also the Xgl (never tried) http://research.edm.uhasselt.be/~jori/page/index.php?n=Misc.DualSeatX/ could be interesting, but it is even more dead... Anyone volunteers to make xephyr-with-gl-acceleration live again?

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

Andrzej, thank you for input :-)

I am currently using gdm, and I can play games 3d games - without having to use xephyr :-) Though for some of us xephyr should be a good (or only) option.

On 08/20/12 05:15, Khumarahn wrote:
> Question #190502 on Light Display Manager changed:
> https://answers.launchpad.net/lightdm/+question/190502
>
> Status: Expired => Open
>
> Khumarahn is still having a problem:
> Andrzej, thank you for input :-)
>
> I am currently using gdm, and I can play games 3d games - without having
> to use xephyr :-) Though for some of us xephyr should be a good (or
> only) option.
>

@Khumarahn: Are you using gdm2 or gdm3?

--
Save your e-mails: apt-get remove --purge evolution

I use gdm2. I am scared to update my system because it may bring gdm3 some day :-)

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

not answered

I've only gotten so far in my attempts with multiseat. The best success i had was using KDM. I tried using lightdm and got hit with this bug: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/997483
Both screens have a login greeter, but neither has a password input field. Go figure.

This is bug #976124:

https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/976124

That has just been marked low priority due to it affects few users...