How to merge hard drives?

Question

Hard disks

Good afternoon!
After the mass replacement of hard drives on laptops with solid state drives, a certain number of good HDDs remain, for which it is necessary to find a new application.
One option is to mount it in a case and use it as an external hard drive. But another option is of interest
. Is it possible to combine them (about a dozen) into something similar to a NAS in order to upload and store backups there?
If yes, how would you recommend?

Answer 1

A dozen disks are already on the verge of the capabilities of cheap motherboards, usually if you are short of money (you don’t want to spend more than necessary on this task), then your option is the cheapest possible computer (at the moment these are either motherboards with a built-in processor, although there is usually little sata, or amd socket am3 + any hair dryer + the minimum amount of ram, choose by the number of sata ports) + sata controllers, including usb.
Do not mindlessly combine ALL disks into a single RAID, this is fraught with a significant decrease in performance. Test the speed of each and combine in RAID only with equal values, you will almost certainly get something like 2 RAID5 (3 disks each) and a pair of RAID1 (two disks each), then cut a single file system on each and mount it in folders named after subject matter and speed
ps the second alternative, scatter disks over several machines, and use it over the network (there are a lot of solutions), though it will be convenient to do this only from linux, well, you can keep virtual machines, .. get out somehow, but this is the cheapest solution (no need to buy optional)