An assembly includes: a server rack; first side and second side outer rails attached to the rack and positionally fixed relative to the rack; a support device attached to the rack adjacent to a rear of the rack; a computer network switch having a port side positioned adjacent to the rear of the rack; and first side and second side inner rails attached to the network switch and positionally fixed relative to the network switch, the inner rails being slidably attached to the outer rails. The network switch is movable between a retracted position and an extended position, and the support device is located such that the support device physically blocks the network switch from being removed from the rear of the server rack.