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You can run multiseat anywhere with a recent xorg (not just fedora). I run multiseat on Ubuntu 9.04; only had to edit xorg.conf and gdm.conf. Though I do have two video cards.

You are correct, you cannot move windows between separate X sessions. But you could use synergy to access both seats with the same keyboard/mouse.

Read more about generic multiseat here:
http://blog.chris.tylers.info/index.php?/archives/14-Multiseat-X-Under-X11R6.97.0.html

You are on the right track... you are describing something similar to "Multiseat X".

Read more here: http://blog.chris.tylers.info/index.php?/archives/14-Multiseat-X-Under-X11R6.97.0.html

Unfortunately, if you just have a dual-head video card, I believe you need to run xnest or something similar to have separate X sessions on two monitors. However, having two video cards is easy.

I had multiseat working in Ubuntu 8.04, and it's working now in 9.04. I only had to modify xorg.conf and gdm.conf. (Though it did take several hours to get all the usb devices worked out, as well as the console-kit sessions.)

I have two monitors on a single pcie nvidia card as Seat0, and a single monitor on a second pcie nvidia card as Seat1. Two usb keyboards, and two usb mice. One computer.

If I want to connect all 3 monitors, I login (as two different users) to both seats, and run synergy.

I have a stable 4-seat system at home that I use daily -- along with my wife and two daughters. It takes a bit of work to get a multiseat system set up, but once you do, you save electricity, hardware costs, and admin costs, and in a school setting you could deploy the same configuration across a number of systems. Previous posts have mentioned my blog entry and related discussion: http://blog.chris.tylers.info/index.php?/archives/ 14-Multiseat-X-Under-X11R6.97.0.html -- it's getting a bit dated but the basics will send you in the right direction. (There are other ways to do multiseat, too, and I'm including them in a chapter of an upcoming O'Reilly book).

My system is a 32-bit AMD (Athlon XP 2800) with one AGP and three PCI NVIDIA cards, along with one PS/2 keyboard+mouse set and three USB keyboard+mouse sets. I have 1 GB of RAM, which has worked well until recently, when I added a Xen guest domain with some web services and dropped the amount of RAM available for multiseat use ... so now I'm shopping for a 64-bit box with a bit more RAM. We run standard desktop apps: OpenOffice.org, Firefox, the Gimp, various photo management programs, music players, Evolution, Google Earth, and so forth, and the performance is quite acceptable.

3D desktops (Compiz/Beryl) do work in this configuration, but this machine is a bit under-powered to make them work really well. When I get my new box I expect that we'll all be running Compiz :-)

I set up a K-12 school in Bolivia using 12 Multi-Head PC's driving 3 stations each giving 36 terminals. The original version used the Backstreet Ruby kernel patch and a hacked X server. It has been running stable for 2 years now. I have been trying out X.org which is stable with new (9631) Nvidia drivers (we use one onboard Nvidia graphics card and 2 Nvidia PCI graphics cards - around $50 each).

I looked into an X terminal solution but the performance was not good enough. We want to run kids educational games that have nice graphics and things changing quickly on the screen - LTSP is too laggy. The machines use Athlon XP 2500+ processors with 512MB RAM.

Getting a stable configuration can be tricky. Chris Tyler's blog here:
http://blog.chris.tylers.info/index.php?/archives/ 14-Multiseat-X-Under-X11R6.97.0.html
has useful tips that helped me out - you have to wade through some crud to find them...

Ideally we would like to use VMware or Wine so the kids could play Windows educational games - they are lots of them and the kids love them. I have not been able to get the games to run on Wine however and with VMware, the performance is not good enough. We set up another Elementary lab with Win98 installed - PIII 750's with 128MB and 40GB 5400RPM drives is plenty for the type of games they run.

Good luck!
Feel free to contact me if you have any questions.

There are a lot of different ways to do this under Linux; someone has already posted several links to some resources. The easiest way I found, and the way I've been running my two-seat, single-machine setup at home for about a year, is simply using the capabilities of newer versions of X Windows as described on Chris Tyler's blog (included in those links earlier).

All of the other methods I've seen require non-standard kernel modules or non-standard X servers, etc. This way uses standard software, and I think it should work for most modern distributions (I'm using Gentoo).

What you need hardware-wise:

1. One graphics card per seat. I have an old AGP Radeon 9000 and a super-old PCI Matrox Mystique.
2. A monitor extension cable if you want the seats far apart. I first bought a 15ft brand-name one from Buy.com that was absolutely worthless (thin cable, ridiculous ghosting even at low resolutions) - then I bought this "generic" one which works perfectly.
3. One keyboard/mouse pair per seat. One of my seats has a PS2 keyboard and a USB trackball, and the other has a PS2 mouse and a PS2 keyboard on a PS2 to USB converter that works perfectly hanging off the end of a 10ft USB extension cable.

The software setup is described fairly well in Chris Tyler's blogs (don't skip the comments - there are useful tips from others in there, and on this followup page), but here's the basic idea: You run two separate X instances, each with a different ServerLayout section in the config file. They obviously need to point to different video cards (and I found that using the "SingleCard" option was necessary to get both to work), and you also need to separate the input devices between the two. The best way to do this that I know of (again, avoiding odd kernel modules or other software) is evdev. It's somewhat complicated, but it lets you specify input devices based on where they are plugged in or their specific model numbers, etc. It's fairly flexible.

Once you have two separate X instances up and running, it's a fairly simple matter to get gdm (and I assume most other *dm applications) to launch both automatically with independent login screens.

Good luck!

There are a lot of different ways to do this under Linux; someone has already posted several links to some resources. The easiest way I found, and the way I've been running my two-seat, single-machine setup at home for about a year, is simply using the capabilities of newer versions of X Windows as described on Chris Tyler's blog (included in those links earlier).

All of the other methods I've seen require non-standard kernel modules or non-standard X servers, etc. This way uses standard software, and I think it should work for most modern distributions (I'm using Gentoo).

What you need hardware-wise:

1. One graphics card per seat. I have an old AGP Radeon 9000 and a super-old PCI Matrox Mystique.
2. A monitor extension cable if you want the seats far apart. I first bought a 15ft brand-name one from Buy.com that was absolutely worthless (thin cable, ridiculous ghosting even at low resolutions) - then I bought this "generic" one which works perfectly.
3. One keyboard/mouse pair per seat. One of my seats has a PS2 keyboard and a USB trackball, and the other has a PS2 mouse and a PS2 keyboard on a PS2 to USB converter that works perfectly hanging off the end of a 10ft USB extension cable.

The software setup is described fairly well in Chris Tyler's blogs (don't skip the comments - there are useful tips from others in there, and on this followup page), but here's the basic idea: You run two separate X instances, each with a different ServerLayout section in the config file. They obviously need to point to different video cards (and I found that using the "SingleCard" option was necessary to get both to work), and you also need to separate the input devices between the two. The best way to do this that I know of (again, avoiding odd kernel modules or other software) is evdev. It's somewhat complicated, but it lets you specify input devices based on where they are plugged in or their specific model numbers, etc. It's fairly flexible.

Once you have two separate X instances up and running, it's a fairly simple matter to get gdm (and I assume most other *dm applications) to launch both automatically with independent login screens.

Good luck!

http://linuxgazette.net/124/smith.html
http://www.google.com/search?q=multiseat+x
http://cs.senecac.on.ca/~ctyler/ruby/
http://blog.chris.tylers.info/index.php?/archives/ 14-Multiseat-X-Under-X11R6.97.0.html
http://www.linuxtoday.com/infrastructure/200512070 0126OSDTHL

I have a link that will let you use the equipment you mentioned handle two seperate logins.http://blog.chris.tylers.info/index.php?/ar chives/14-Multiseat-X-Under-X11R6.97.0.html

I have never tried this solution but from what I have read in the past it seems to be getting easier to handle multiple input devices and displays. I would agree with others that if you wanted the same login to hanle both sets of keyboards mice and monitors you run the risk of confusing the operators or the programs.

I see a lot of misinformation here about the levy and private copying in Canada.

Let's set the record straight: private copying of music in Canada is legal, and the levy still applies to CD-Rs and cassette tapes.

For more info and links, see this previous blog post: It's Not Illegal if the Law Says You Can Do It