A testing server performs a test to check whether servers properly execute failover. The testing server includes a generation unit, a transmitting unit, a testing unit, a restoring unit, a judgment unit, and a power control unit. The generation unit generates an image file of an OS. The transmitting unit transmits the image file to to-be-tested servers. The testing unit injects a simulated fault into a server among the servers to which the image file is transmitted and performs a test. The restoring unit, each time the testing unit performs a test, restores a status of the to-be-tested server to a pre-failover status. The judgment unit judges whether the restoring unit properly restores the status. The power control unit, when the judgment unit judges that the status of the to-be-tested server is not properly restored, turns off power of the to-be-tested server and turns on the power again.