I’m running my media server with a 36tb raid5 array with 3 disks, so I do have some resilience to drives failing. But currently can only afford to loose a single drive at a time, which got me thinking about backups. Normally I’d just do a backup to my NAS, but that quickly gets ridiculous for me with the size of my library, which is significantly larger than my NAS storage of only a few tb. And buying cloud storage is much too expensive for my liking with these amounts of storage.
Do you backup only the most valuable parts of your library?
I admit this is not a helpful answer but…
If you want to have hundreds of gigabytes or more of media storage plus backups, its going to be expensive. There is no secret cheap way.
This is what makes debrid options so appealing. You can amass terabytes of media data for a cheap monthly cost.
You can then supplement that with a small nas or drive of rare or hard to find media / offline selection in which case you could probably run raid 10 with the small amount that you would actually need to backup.