Hi. Thanks so much for the replies. I will try to explain my situation in more detail here. So I've got like ~2TB of work related files right now. Thats just something that I've created in a few years. I also have 2 NAS type of 2TB Hard Drives that are used for servers and stuff. Also I have an old PC lying around that I could somehow use to do this kind of backup system. I don't need to backup everything I have, I just want to keep safe the most recent stuff, maybe about 500gb at a time. Also my files are not in one place, some are in My documents, some are on my projects folder on another hard drive, thats the way the software I am using is handling project files.
So as far as I understood, I need 3 times the storage space to backup my files correctly, right? I would use two HDDs in RAID, and one more to make a backup? Can I do this sort of thing with FreeNAS OS?
Also, I am doing this for my self for my home PC