During the filming of Star Wars: The Force Awakens there was a problem with people, hobbyists, and the media attempting to film and take photos of the Greenham Common set for the Resistance base. Sometimes they were successful. The problem there was the set was public property and owned by the people. Star Wars: Episode VIII will film some exteriors in Dubrovnik, Croatia and they are apparently cool with not letting filming of the sets and locations happen. Apparently there is a solution they are allowed to use there according to MosCroatia.com:

There is a special team with drones that will remove the uninvited drones so that no recording can be conducted by the public.

They also seem to think that 600 guards are being posted to make sure no filming of the production takes place.

It is always a little tricky dealing with translations to get at the gist of these articles. But it appears they say there will be anti-drone drones in the sky, 600 guards, and Dubrovnik was given 38 million Kuna (about $4.3 million) to make it happen.

Thanks to @ELIX11_SW for the heads-up!