I am confused with the arrest of Timur Ivanov. Ivanov is a close ally of Sergei Shoigu. FSB going after Ivanov seems like their signature move where the real target is somebody higher-up in the ranks e.g. Shoigu. However, Shoigu is favored by Putin. Putin is the head of all intelligence services in Russia.

There is the following commentary that this is apparently the start of the war between Russian elites. However, what I can't understand is how can somebody in FSB just go against of what it seems Putin's interests himself? Basically going against your boss.

I wonder how something like FSB operates in reality? Is it more like some monolithic homogeneous institution where everyone knows their place and act on given orders that travel top-down. Or is it more like Sopranos -- for all six seasons your are the boss, but very mortal and very dead by the end? And this is how you get a new boss with his own clique now running the show.