Like everyone else, raid is not a backup.
dont use hardware raid, use some sort of software defined thing, like zfs or btrfs.
the last suggestion i saw for zfs that seemed credible was to use mirrored pairs of disks.
So basically, buy a second 12tb drive, slap both in some sort of old desktop, setup truenas, and sort out a backup strategy.
I really need to start messing with software raid, it seems promising, my only question is.. doens't it need a beefy cpu, enough ram or cache and decent storage?
Backups are more important than raid levels.
Have automated backups that comply with the 3-2-1 rule first, you can migrate raid levels later.
Should be using software-defined storage, like ZFS. Provides snapshots, rollbacks, compression, and optionally deduplication and encryption. ZFS is both a filesystem and volume manager. Good stuff.
I have a 2 bay NAS in RAID1 that houses all of our documents, family photos, etc. This is pushed to the cloud with up-to 30 day versioning of individual files.
RAID is for data redundancy. Cloud is for backup.
no raid, get a second one as off-site backup
At the bare minimum, or at least to start get data in a raid that losing a drive or 2 won't cause you to lose everything. You're not out of the yet. If you can't lose your files you want 2 separate copies in different machines, preferably at different locations. Be that a cloud service or a remote server.
My files are on my local NAS server that are also backed up to my remote NAS server at my dad's house over a VPN. Essential files (not my plex media) are also in a 1tb cloud service. 3-2-1 backup plan is probably ideal but I'm pretty happy with my 2.5-2.5-1.5 approach 😅. 3-3-2 for critical stuff and 2-2-1 for everything else.
For data protection, you must first keep proper backups. RAID is for uptime, and for a homelab it's not always needed. Backups first (external drive, cloud), then RAID.