I'm considering building a NAS and I'm evaluating my options. Power consumption is quite important for a server that is always on. Just to give you some context, these are the options I'm considering:
- Raspberry Pi with a USB hub and external hard drives
- Retired gaming PC with internal hard drives
- Save myself time and effort and pay a cloud provider
The gaming PC is definitely not low power and keeping it always on is not an option. The primary purpose is to use it for backups, so if I can configure it to Wake-On-LAN and hibernate after a short period of inactivity, it could be an option.
I think the peak power consumption of my old Raspberry Pi is about 1W. The power consumption of the hard drives depends on what I end up buying, but it seems like it typically ranges from 2W to 10W, and I'll probably get somewhen between 3 to 6 drives. That means that power consumption for the drives would be somewhere between 6W and 60W. Being able to control when the disks are sleeping could have a big impact on the power consumption of the NAS.
Some external hard drives/docking stations/enclosures advertise that they have a sleep mode. One said that the disk would sleep after 10 minutes of inactivity for instance. It also seems like some manufacturers provide drivers that allow you to configure the time before the disk sleeps.
What I haven't found any proof of (yet?), is that there are external hard drives that allow the OS to decide when a drive should sleep. Does that exist? If so, what is required for that to work?