Finally planning to setup that raspberry pi 4 rig. I am planning something similar like the rig(with external drives) in the reference wiki . In the reference raspi rig, the power supply is a 500W 12V supply. (assuming the drives take 1.5A at spinup and 0.2A at normal operation this totally this totally fills the requirement). I am setting up 20 drives per raspi(1.8A per drive spinup). Lets say I setup 6 such rigs → 3000W requirement. Now I can go and buy a 3000W supply, but I am thinking of doing something similar to staggered spinup. Start every raspi in intervals of 20secs, so that a single 800-1000W smps can be used for all 6 rigs. I know that you can setup boot delays in raspi’s config.txt, but would that delay the spinup of the external drives or would the disks just anyways powerup?
TL;DR - is there a way to delay bootup of external hdds connected to a raspberry pi 4 so that sets of disks can be powered on in a staggered fashion?