I have a Fedora Linux server with Gnome 3. I want to lock / unlock the remote Gnome desktop remotely. How to activate or deactivate it remotely through SSH?
Use gnome-screensaver-command. It is not specific to Gnome 3.
Turn the screensaver on (blank the screen):
$ gnome-screensaver-command -a
If the screensaver is active then deactivate it (un-blank the screen)
$ gnome-screensaver-command -d