Synergy mouse not moving past first screen in dual-screen configuration

Question

I have two dual-screen machines that I want to use Synergy with. Below is a diagram of how it's laid out. My server is a Windows 7 machine, and the client is a Debian Wheezy machine with Gnome3. This machine is a pretty standard installation with nothing too extraneous.

+----------+ +----------+ +---------+ +-----------+
|  Server  | |  Server  | | Client  | |  Client   |
|  screen1 | |  screen2 | | screen1 | |  screen2  |
+----------+ +----------+ +---------+ +-----------+
                                     ^

I've gone through the HowTo tutorial to autostart Synergy and it is mostly functional. The login screen is a single-screen setup and is mirrored on both displays. My problem is that after logging in, Synergy does not move any farther to the right on the client's first screen (as noted by the caret at the bottom of the above diagram). The mouse stops right at the boundary between the two client displays. I suspect that the issue is something like the answer given here: Synergy is starting up too early, before the screens have been defined (or rather redefined) for the user's session. Unfortunately, that question pertains only to the KDE environment.

I've tried modifying the 85synergyc script (the last script from the linked HowTo tutorial) to run xrandr (my exact cmd being xrandr --output DVI-0 --auto --output DVI-1 --auto) in order for the displays to be defined just before the client was started. This had a "limited" success: now the mouse moves over to the second display but is bound to about a fourth of the way into the second screen. This suggests to me that the synergy client might be started a little too early. I'm wondering if you may have already seen/resolved this sort of issue previously. I have also tried the solution in the linked Superuser article but I'm not able to find or determine what the GDM equivalent of KDE's Xsetup is. As a last resort, I killed all synergyc processes and then started another with the same parameters as the one being called in my autostart scripts (I'm using encryption). The new instance is able to traverse both client screens perfectly, as expected.

Could this be resolved by adding/moving the call to synergyc somewhere else, after the displays have been defined? Is there a better method to assuring that the displays are set before spawing a synergy process as part of the Xsession?

Answer 1

While I didn't find the reason why Synergy was spawning before the displays were updated, I solved it by adding a startup application entry through Gnome, which I was not able to find in any of the GUIs.

1. Run gnome-session-properties (from a terminal or ALT+F2)
2. Click on the Add button

3. Click on the Browse... button and navigate to:

   • the location of the 85synergyc script (from the HowTo tutorial)
   • OR move the file to another appropriate location (like /etc/opt/synergy/) and select that file

4. Click Save

I've tested this by rebooting the machine a couple of times and Synergy is now able to access the entire dimensions of both screens.