[sammyg2]

Dude, google.
There has been trouble in that little break away province for years. Russia has peace-keepers there and has since the peace-fire was declared. Georgia doesn't like that. They want that province back. They don't like the fact that the province seeks independence from them and Russia is assisting them.
Russia doesn't like the fact that Georgia petitioned for membership in NATO so there are several reasons why relations are strained.
The government of Georgia antagonized Russia with sporadic violence hoping they would lose interest or give up some of their hold. The violence escalated.