This post describes how to auto start synergy client which do not need to use ubuntu host's keyboard and mouse.
$ sudo apt-get install synergy
Edit to use at gdm
$ sudo vi /etc/gdm/Init
at the end
fi
/usr/bin/killall synergyc
sleep 1
/usr/bin/synergyc 192.168.10.220
exit 0
Then you must edit user session file
$ mkdir ~/.config/autostart/
$ vi ~/.config/autostart/synergyc.desktop
[Desktop Entry]
Type=Application
Encoding=UTF-8
Version=1.0
Name=No Name
Name[en_US]=synergy
Exec=/usr/bin/synergyc 192.168.10.220
X-GNOME-Autostart-enabled=true
done.
you can restart gdm.
like this
$ sudo /etc/init.d/gdm restart