Yeah I had tried that, I found that there was one setting that would actually disallow you to even move a window to the other screen, it would snap back, but it SEEMED to work. However, there is still the odd program where it would not work. As testing I even went as far as making a global rule and it still did not work.

I am thinking of maybe going back to nvidia driver and trying the separate X displays again (the nvidia settings box has the option so that's why I need to use nvidia driver). Only thing I find it's very tricky to get them in the right order since the drag/drop of the displays gets really finicky in this mode. But once I can get seperate X display to work, then maybe it's just the thing of forcing everything to the centre (primary ex: 0.0) display. Then I can have some kind of exception that will launch VNC into the two side monitors. I am wondering if I can have a script that does that, as it can probably set the environment variable from the main dektop then set it back. Once the VNC sessions are open I don't have to worry about opening stuff off the side monitors anymore. Just as long as opening stuff from the primary actually sticks properly. My experience when I tried separate X displays is that stuff STILL randomly opened in the wrong one, but it seemed to do it mostly from the side monitors. I did not play around with it long enough though, as I had trouble getting the order right and it was a little dizzying with everything being out of place. But maybe it's my best bet to try to get it working again. Just need to figure out how to order them right. The GUI tool is really finnicky. For some reason in CentOS there is no xorg.conf file so anything that tells me to go in there won't work.

The xinerama solution looks interesting, where do I put the -geometry parameter and is it something that will work 100% of the time? What about if a dialog is spawned from a program that is on the side monitor will the dialog stay on that monitor or still go where -geometry is set?

You can pass the -geometry option (or any X Server option) directly to the X Server via VNC.
https://support.realvnc.com/knowledg...l-mode-desktop

The -geometry option allows you to specify the size and position of the window on the display. The geometry specification has the format:
http://docstore.mik.ua/orelly/linux/run/ch11_01.htm


I honestly don't know. Sorry-

Newer distros are weird they got rid of lot of the typical config files like xorg.conf, so it really limits options.

As a totally unrelated issue, I tried to update my BIOS but it only made the issue worse, basically the issue is that this motherboard for some reason does not like addon video cards, it POSTS very slowly, sometimes goes into a loop etc... I said screw it, and just took the video card out. So stuck with just one monitor for now. I think I'm going to try to revisit a synergy or similar method. At this point I'm even contemplating looking into what it would take to build a piece of hardware that does it. Basically a device that the mouse and keyboard plugs into, and then it has USB out for each system. The device would emulate a generic HID keyboard and mouse, and then the real keyboard and mouse plugs into the device and by pressing a button it would switch which one it controls. I guess almost like a KVM, except it would be seamless and faster. I could technically use a KVM to do this but KVMs are slow since they don't emulate the keyboard/mouse to the OS so it's like plugging/unplugging all the time.

I'm going to keep trying to get Synergy to work meanwhile. Though from what I'm reading on their forums even the newer versions crash a lot. It seems the whole project has gone downhill.

I might also look into just going 4k, then I can probably actually code on just one monitor as there will be way more real estate.

As for getting multi monitor working on a normal setup I think I'm going to just wait until Wayland is more standard and hope that they addressed a lot of the issues.

I wish I could even get Wayland to work on either of my systems to try it -- there's a lot of promise there but I can't even open a Gnome or Plasma (KDE) session on Wayland yet, sadly.
I am a bit worried though because Wayland is the future of Linux desktops so if multi-monitor is a bad as or worse than X11 then that's the end of multi-monitor on Linux for good.

After reading a few articles about Wayland it sounds like there is good intention for the replacement for X but I wasn't able to find any documentation suggesting that Wayland developers are working on it.

Has anyone seen or found anything on the implementation of this project?

Maybe this is what's holding up the progress?

https://wayland.freedesktop.org/testing.html

------------------------------------------------------
I hope too that this get's resolved.
Looks like it's going to take time.

I ended up just going back to the Synergy route, but that program is a piece of crap and crashes constantly. So I still need to figure out a long term solution. I spend more time having to SSH into all the devices so I can restart the service, than actually using it.

I might have to dig through the synergy code and check what functions/classes/etc are used to work with the keyboard and mouse (capturing keys etc) then I'll just write my own.

Sorry to hear synergy keep crashing and your spending more time having to SSH-
Wish I knew what the answer was:-

Good luck!

I may look at writing a "watchdog" program, just need a way to monitor that the process is not responding. Then it will do a kill -9 and restart it. The server usually needs to be kill -9'ed, the clients only need to be restarted. On the synergy forums it's fully of people saying it's crashing, even the latest version. They really need to streamline the code and figure out the crash issue. I know how hard that can be to do myself though, but it needs to be done. Once I can get that working I may have a usable scenario. The RPI browser also crashes all the time, well it just closes on it's own, so to remedy that I'll just turn the RPIs into a thin client and have them VNC into a server session. VNC is decently usable for regular tasks, at least I'll try it and see.

It's too bad the x2vnc was not working out as I liked the idea of that one, but mouse cursor was way too choppy.

There's got to be a way to find out what's making it crash. Maybe try writing to the Developer:
Chris Schoenemans?
https://en.wikipedia.org/wiki/Synergy_%28software%29

I found him on Linkedin. The rest of the team members that helped him with Synergy are on that page.
https://www.linkedin.com/in/chris-schoeneman-b081871

-::-Try launching Synergy via the terminal and see if it throws any errors. The errors might give a clue as to why it's crashing.-::-

When you launch from a terminal it runs in the background, ex: not like any other app where it would "take over" the console. It just goes back to the prompt, but it's running in background. Kind of like a service I guess. There are no logs that I know of. I imagine the devs are constantly being bombarded with crash reports already. The cause seems to be with copy/paste. If there is something on the clipboard from one screen and you try to paste on the other, it's SUPPOSE to work, it's a feature, but really, it just locks up the system then crashes. I presume the normal crashes may possibly be related to that like if you carry mouse over with a non empty clip board it has a certain chance to crash.

At some point when I feel inclined to I will dig through the source and see what it would take to make a streamlined version of it.

What a mess:-
Happy digging through src.

My latest experience may be unrelated to your problems, but maybe not:

Recently, I have been having severe problems with synergy getting ridiculously sluggish and consuming a lot of CPU. Turns out that my scripts for killing off old synergyc clients wasn't working because the command "killall" wasn't installed on a couple of the clients (very minimal new RAMboot installs; solved with "apt-get install psmisc").

The result was that I had multiple instances of synergyc running on a couple clients. This caused sluggishness and also caused some logs somewhere to balloon in size (still don't know where). My usual habit when these problems crop up is to click on all my "restart synergy script" icons, and this would just end up making the problem even worse.

So, I'd check each machine to make sure only one instance of synergys/synergyc is running on each.