Written for Synergy 3 (v3.7.2) and Synergy 1 (v1.21.4), checked 3 October 2026.
Product: Synergy 1 and Synergy 3
Operating system: Linux
If a key on your Linux server types the wrong key on a client, remap the key on the Linux server itself, as below.
For example, the right Alt key on a Linux server may send ISO_Level3_Shift (Alt Gr), while the Windows client expects Alt_R (right Alt).
To remap a modifier key such as Alt Gr for one client in Synergy 1 or Synergy 3 instead, see: Swap or remap modifier keys (Ctrl, Command, Alt Gr) in Synergy 1 and Synergy 3
Remap the key on the Linux server
This works only in an Xorg session; xmodmap has no effect on Wayland. To check, run echo $XDG_SESSION_TYPE, which returns either x11 or wayland.
The example maps your Right Ctrl key (keycode 105) to Alt_R, so pick a key you don't use much. Right Ctrl then works as Alt_R on your client computer.
- Open the terminal.
- Create the mapping:
echo "keycode 105 = Alt_R Meta_R Alt_R Meta_R" > "$HOME/.Xmodmap"
- Apply it now:
xmodmap "$HOME/.Xmodmap"
- To apply it every time you log in, add it to your autostart:
mkdir -p ~/.config/autostart printf '[Desktop Entry]\nType=Application\nName=Xmodmap\nExec=sh -c "xmodmap ~/.Xmodmap"\n' > ~/.config/autostart/xmodmap.desktop