Synergy KVM-thing

If you have multiple computers with multiple monitors, Synergy is a great way to keep your hands on a single keyboard & mouse. It’s kind of like a KVM, but it’s not.

I have 2 monitors on 1 computer (my main desktop PC) and a laptop that I haul from home to work. Now, I can keep my hands on one keyboard and mouse while I slide my mouse from my big 19″ main screen, over to the right to my 17″ screen and then … magically to the right again onto my laptop!

You can slide from your PC to your Linux to your Mac. Keyboard input follows the mouse. You can copy/paste across boxen! It’s magic, and it’s FREEE!

Get Synergy
Read a good tutorial. (I thought it was overly verbose and then I needed to read it to figure out one concept)

I was up and running in < 5 minutes.


1-27-21 update:
I hadn’t been using Synergy for a while but with COVID, I needed a better computer setup. I’ve got 2 Windows computers with a total of 3 monitors. It’s wonderful! I paid $30 for it and it’s, no brainer, completely worth it!
I have 2 monitors on the bottom and 1 on top. So I used the custom configuration option to align the cursor movements better. Here’s how:
– Start Synergy
– export the current configuration with File | Save Configuration as…
– modify the configuration file with tips from Synergy (1)
Mine looks like this:

section: links
up(50,100) = Tobuscus(0,100)
down(0,100) = PSC-ALT-49(50,100)

– Point Synergy at the config file with the “Use existing configuration” option.
– Profit!


  1. TJIC says:

    I was just thinking of getting a second monitor myself!

    Of course, this being a linux box, I’ll need some other solution. I suspect that there’s an even chance that KDE supports this auto-magically.

  2. Lee says:

    Not only will this work on linux, but you can copy and paste between a PC, Mac, and linux!

    But read closely, it’s a bit different from “a software kvm”.
    KVM: 2 computers, 1 monitor, 1 keyboard, 1 mouse
    Synergy: 2 computers, 2 monitors (1 plugged directly into each respective computer), 1 keyboard, 1 mouse

  3. Chantage says:

    A stranger passinbg by… (I just typed out of whim)
    I have used x2vnc to control multiple machines from one computer.
    It works exactly like what you described but no cut & paste across
    computers. If it’s not too complicated, I will switch to Synergy.
    Thanks for the great info.

  4. Lee says:

    Chantage, you are most certainly welcome! After you’ve tried it out in X for a couple days, leave another comment saying how well you like it.

  5. Lee says:

    I just upgraded to the latest “Experimental” version 1.2.8 and it seems more reliable than the 1.2.5 it replaces. On 1.2.5, I would sometimes lose the ability to use the [shift] key on the second computer and sometimes copy-paste would stop working between machines and sometimes the host computer would lose keyboard and mouse entirely until I shut down (a mere reboot wouldn’t fix it).

    Tech note:
    On the secondary computer, I used to tell it to connect to the -name- of my primary computer. I changed that to the IP address because Windows networking sometimes takes a long time to tell Synergy where to find the machine (that’s a problem with Windows networking, not Synergy).

  6. Lee says:

    Synergy 1.3.0 just came out.

  7. Travis says:

    I have tried several times to access the link posted above but all I get is a blank page. Is there another link to be used?

    Thank you.

  8. Lee says:

    I just tried it. The link works. You can google for “synergy”. It’s the most popular usage of that word on the internet. (!)

  9. thummper says:

    WOW, this sounds exactly what I’ve been looking for…almost. I was just thinking that someone should make something like this, but with the added ability to drag, say, a file from one desktop to another and it knows to do a file transfer in the background, etc. Anyone know if there are any competitors out there I could check out as well?

  10. Lee says:

    Glad I could help. I had seen a couple pay-ware software products that worked similarly but they looked like they’d work as well or less well than Synergy. Sorry, I don’t recall any product names.

    The drag and drop stuff can be done “well enough” with Windows file sharing, Samba and/or FTP . I haven’t seen any automated drag and drop products.

  11. kots says:

    Ok here’s my question, i have a pc and a mac and only 2 dvi monitors. so im only working with 1 computer right now (my pc) cause im spoiled and must work with 2 monitors per computer.

    i want both my dvi monitors to be either both working on my mac, or both on my pc. not 1 for each. is this possible with synergy? if not any other solutions, ive reseraching forever and only could find a very expensiv kvm.

  12. Lee says:

    Kots, invest the extra 30 seconds and click on the Synergy link above. It will tell you whether it can do it or not. I know the answer to your question.

  13. thummper says:

    getting a pain in the butt bug, but im not sure its easy to describe. I have 2 vista machines linked with synergy. Everything is fine on the primary system, but the one that is connecting to it has a wierd mouse movement issue. I notice it when I play a game on it. the mouse look on all games I have tried (stearing the camera by click-and-draging around) is messed up. I get the exact same result when I tried to use a tablet instead of a mouse. If I click on the left side of the screen it will only rotate to the left, same on the right. It doesnt track with the mouse movement, the rate at which it rotates right/left is determined by the distance of the place where it was originally clicked from the center of the screen, and it starts / stops rotating when the mouse is moved horizontally or stopped.

  14. Lee says:

    When playing a game? A snazzy first person shooter, full screen game, yes?

    Have you looked at the (rather good) FAQ, Known Bugs, Troubleshooting et all off the Synergy main page?

  15. thummper says:

    Yes, and had there been mention of this issue I would have certainly saved your realestate, however the only two mentions were of someones mouse popping in and out and moving to the corner, and someone else’s mouse moving extremely fast.

  16. Lee says:

    Sorry, I don’t have a solution. Maybe someone else (Beuller? Beuller? Beuller?) will…

  17. Qwoggle says:

    I have this same problem… My mouse look in World Of Warcraft is all messed up. Has anyone found a solution to this?

  18. thummper says:

    Multiplicity does basically the same thing but has a support channel and works for me with eq2. It’s about $40. The prob with that one, though, is that when on vista it works once, then if you close the program you cant open it ever again. They have said that the full version is updated to support vista, but the demo hasnt been yet, however I am waiting till I can verify that it works with the demo before I go and buy it.

  19. Way says:

    I also have the mouse-look problem on the client PC when running WoW. Mouse-look goes beserk. I just work around it, but often forget and it drives me nuts :(

    Other than that though, amazing software. Love it.

  20. Smedis says:

    I also have the mouse-look issue. It behaves exactly as Thummper described.

    For me, it happens on both the server (Vista64) and the client (WinXP SP2). The games are not fullscreen, just maximized windows. Note that everything works just fine, except mouse-look.

    It seems it’s related to how mouse-look works. The application forces the mouse cursor back to center (e.g. SetMousePosition) any time you move the mouse. The mouse cursor is hidden during this, so you don’t see it.

    Ahh, I just tested my theory and it’s correct. Synergy doesn’t detect when other applications sets the mouse cursor properly.

    The easiest way to see what’s going on is to Synergy-move the mouse on the client. Then move the client’s cursor with the client’s own hardware mouse. Then move it with Synergy from the server again. You’ll see that Synergy missed the movement from the other application (mouse driver on the client’s machine in this case).

  21. dtm says:

    Guys, I have synergy 1.3.1 set up with the synergy server running on MacOS 10 and the synergy client running on Windows XP. It works perfectly until I run Rappelz (a fullscreen MMORPG) on Windows. Is there any workaround? I am reading that other fullscreen games can run, so is Rappelz an exception or is there another way to do things? I haven’t had any luck with putting the synergy server on windows and the client on macos; I tried but it just isn’t connecting at all. Does the server work substantially differently than the client does on Windows, so that maybe it’d work that way?


  22. dtm says:

    BTW, I meant that when I run Rappelz, synergy stops working altogether. No more console, either mouse or keyboard.

  23. dtm says:

    I thought I’d also note that synergy magically doesn’t work on my MacOS 10 based synergy server, at any moment that joost is in the foreground. Joost is a java-based fullscreen movie player.

  24. dasniper says:

    Is there anyway to make it so on the server machine it does not lower down the full screen game im playing when I switch my mouse over?

  25. idru says:

    Turn on “Don’t take foreground window on Windows servers” in Options on the computer running as server.

    Having the same problem with mouse going wild in WoW.
    Turning off hardware-cursor ingame actually seemed to helt a little, but it’s still unplayable using mouse-movements.
    Two-boxing with /follow 90% of the time, i just have a second mouse on client for times i need to control the char on that screen.

  26. Micah says:

    To play 3D games with Synergy:
    Check the “use relative mouse moves” in the synergy server configuration and bind a key to “lock cursor to screen”. When you are on the client machine press the key to lock the cursor to the screen and then your mouse will work for games there. Of course, you can’t get your mouse off the screen without unlocking it (press hotkey again) but it’s better than nothing.

    The other option is to use different software which can be found at

  27. Nick Bolton says:

    You may be interested to know that Synergy+ is continuing the development of the original Synergy.

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