A rack for a datacenter or other environment may define an internal width configured to receive rack-mounted units of a predetermined width. An adapter may enable operation with a computing appliance having a maximum width smaller than the predetermined width. The adapter can include a tray with a footprint having the predetermined width and a mount for supporting the computing appliance within the footprint of the tray. The tray may support a power inverter that receives from a direct current power supply and provides alternating current to the computing appliance. The tray may also support a patch panel having a network port accessible from a front of the tray. The patch panel can be communicatively coupled with the computing appliance to provide networking communication with the computing appliance through the second network port.