Oh, what fun!
I have gone through a couple different iterations. I started just tossing a bunch of disks into a PC running Linux, using Linux software RAID. That worked fine, but the PC itself was large, hot, and loud. Also, I had a power supply die and take a couple of drives with it. Which was no fun. Initially videos were played on an OG Xbox using XBMC (now called Kodi), but the move to HD meant I had to change. (A shame, too; that Xbox was a tank, and XBMC was pretty user friendly for the time.) I then tried a media PC. Windows Media Center lasted about a week, but the UI was just awful. All of my files were pretty meticulously organized so they worked well with XBMC, but stupid WMC just showed me large icons with "X:\Media\Movies\The..." -- I mean, come ON, Microsoft. So I switched to MediaPortal, which was (is?) a fork of XBMC. Much better.
However, it wasn't a scalable solution. I wanted to be able to watch my stuff (or listen to it) from any TV in the house. So my next stop was using Raspberry Pis with Kodi. That worked OK, but I found that the rest of the family wasn't using them.
It was around this time that I discovered Plex, and that was a game changer. Nobody needed an extra box; the kids both had game consoles in their rooms, and I had Rokus deployed in the main family room and my bedroom.
That got used (and still does).
Anyway, when the most recent PC (Plex server) died, I was short on funds. So I got a cheap $80 refurbished office PC, put the Plex storage (now just a pair of 16tb drives) in USB enclosures, and ran like that -- without RAID. Needless to say, I was holding my breath.
My financial issues cleared up, and around that time, Newegg had refurbished Synology units. Old ones (DS1815+), but I had no intention of running any applications on it. I ordered one, along with another pair of 16tb drives. I set it up with the new drives (thus giving me only 16tb of space), then migrated all of the data from one of the externals. I then pulled the external out of its enclosure, popped it in the Synology, and expanded the pool to 32tb. Then I migrated the other external and repeated the process, kicking me up to 48tb. I have since added two more 16tb drives, one as space (so now 64tb) and one as a standby drive. Should one of the drives in the pool die, the standby one will get swapped in and the array will rebuild, giving me time to deal with replacing the dead drive. (Hasn't happened yet, fortunately.)
Overall I'm a fan of the Synology. Clean interface, easy to use, easy to manage. I'm sure other brands work similarly; this is the one I've had exposure to.
I'm still using that $80 PC for now, but I will be replacing it with a modern NUC soon. The i3 in the current box does fine for most hardware transcoding, except when HDR video has to be transcoded. I need a newer CPU for that.
Network is GigE for now; my personal "plan of record" includes building a 10g backbone. The Synology doesn't support 10g, but it does have 4xGigE ports that can be combined. I'm not doing that yet (there's really no need), but we'll see how things develop.
Down the road from that, I intend to get a newer Synology and make it primary, while using this one as a backup. Right now the array has no backup, only fault tolerance. I need to budget some cash for that, but I just bought a new 77" OLED TV, so it'll take time.
All the data is on the network. So for that I've been doing NAS since the mid 90s, when we used to buy the hardware PCI cards.... that was the hard way and it used lots of power.
I remember setting up drive mirroring on Netware back in the day with separate SCSI (or ESDI) controllers. At least Storage Dimensions sold pre-COMPSURF'd drives...
