Answer: Either this is a misunderstanding or your boss is a coward. A competent manager would address performance concerns directly instead of conducting a clandestine search.
Before you jump to any firm conclusions, however, give him a chance to explain. You never know what’s going on behind the scenes. might be creating a new position, or reorganization could be in the works.
On the other hand, if your job is indeed up for grabs, your boss owes you an explanation. A direct inquiry will force him to come clean and give you a chance to negotiate the terms of your departure.
Although the idea of responding to the ad yourself has an appealing touch of irony, a more straightforward approach will allow you to clarify the situation immediately.
Worried about your own job security? For a general assessment, see Quick Quiz: How Secure Is Your Job?