A method is provided for positioning a data center rack relative to a rack-supporting frame. The method includes connecting at least one front attachment member to the data center rack on a front side thereof such that part of one of the at least one front attachment member and part of one of the at least one front attachment member extend leftward from a left end and rightward from a right end respectively of the data center rack; lifting and inserting the data center rack between a left and a right vertical support units until the at least one front attachment member abuts the left and right vertical support units; and moving the data center rack leftward or rightward until a hook portion of the at least one front attachment member engages the left or right vertical support unit to set a lateral position of the data center rack.