Provided is a rack, comprising: a plurality of rack units; and a plurality of lockers each housing a different respective subset of the rack units, wherein respective lockers among the plurality comprise: a first respective barrier disposed between a respective pair of the rack units; a second respective barrier disposed between another respective pair of the rack units; a third respective barrier that is orthogonal to the first barrier and the second barrier, the third respective barrier being moveably or removeably coupled to the rack; a respective volume configured to receive one or more computing devices; and a respective lock configured to secure the third respective barrier to the rack in the closed position when in a locked state.