Combat training of "Patsir" (NATO name "Greyhound") took place in Primorye. It is a Russian combined short to medium range surface-to-air missile and anti-aircraft artillery weapon system. It represents the latest air defence technology by using phased-array radars for both target acquisition and tracking. Basically, what I got from explanations people left in
comments, is that a few air defense complexes are being used. Some of them are a larger range and can overcome targets further away. Then if the targets in question still managed to pass through the smaller defense complexes then this Pantsir-Greyhound came into play. Any targets who managed to get past the defense are meant to be met by canons.