sysop@hub:~/tools/rack-planner$
rack-planner
What goes where in the rack, does it fit, and can the circuit carry it? Add devices, move them around, and the drawing follows. The plan lives in the address bar, so a bookmark or a copied link keeps it.
add a device
The weights and watts of the presets are typical values: replace them with the figures from the data sheet, and use measured draw where you have it. "Arrange for me" puts network gear at the top with patch panels and switches alternating, the UPS at the very bottom and the rest by weight. Unit 1 is at the bottom, as printed on most racks. Related: server hardware guide: rack units, UPS runtime calculator, PoE budget calculator, network hardware guide, small office blueprint.