What is this?

A quick run down of how to build and install a headless Synergy server setup on Armbian. Tested with Buster Linux 5.3.9-sunxi on OrangePiZero (https://dl.armbian.com/orangepizero/Buster_current).

Why?

For someone with a bunch of retro machines that do not have a Synergy server port (and may not be near a machine that does or near one that I'd rather not run a Synergy server on) but do have a Synergy client port, using a headless Synergy server on a tiny SBC like the OrangePiZero makes for a slick, no frills setup to share a single mouse and keyboard among them.

How do I use this?

I've currently got it connect across my Amiga 1000, Pegasos II running AmigaOS 4.1 FE and Pegasos II running MorphOS.

A bit more info

For headless Synergy, we can't use xvfb (a virtual framebuffer) since it doesn't take input from physical devices. We can however use Xorg with a dummy device, which is similar to xvfb, but has the benefit of being able to use physical input devices. The below steps will go through the setup process and enabling a persistent Synergy server from the moment the system boots up.

Setup steps

1. apt update
2. apt upgrade
3. Compile synergy (see below)
4. Copy bins to /usr/bin/
5. apt install xorg xserver-xorg-video-dummy
6. Change hostname to beautify synergy config definition. Edit /etc/hostname accordingly
7. Create Synergy config (synergy is the screen name of the server or don't change hostname and add the hostname as an alias to synergy) and copy it to /etc/synergy/synergy.conf
8. Run xorg and Synergy server: X -config <path_to_your_dummy_config> && synergys -c <your_synergy_config> -f

Start headless Synergy on boot

1. Copy xorg_dummy.config to /etc/X11/xorg.conf.d/ or whatever your distro uses
2. Copy x_dummy.service and synergy.service service files to /etc/systemd/system/ or wherever your systemd config resides - chown both to root:root
3. Reload systemd: systemctl daemon-reload
4. Start X dummy: systemctl start x_dummy
5. Check its status: systemctl status x_dummy
6. Start synergy server: systemctl start synergy
7. Check its status: systemctl status synergy
8. Enable both services to start persistently: systemctl enable x_dummy.service; systemctl enable synergy.service
9. Reboot

To build Synergy

git clone https://github.com/symless/synergy-core.git
cd synergy-core/
sudo apt -y install qtcreator qtbase5-dev cmake make g++ xorg-dev libssl-dev libx11-dev libsodium-dev libgl1-mesa-glx libegl1-mesa libcurl4-openssl-dev libavahi-compat-libdnssd-dev qtdeclarative5-dev libqt5svg5-dev libsystemd-dev
mkdir build
cd build
cmake ..
make

Once built, copy build/bin/ to /usr/bin/