turbulent

Thank you! All of this was very informative. I don't expect my storage requirements to grow that large over the next few years. For my priority (data preservation) - would you recommend ZPool over the current setup?

I have an unraid server (6.12.8) with 2x 20TB HDDs in an array. One of these is a parity drive, the data drive uses XFS. The primary use for the server is backing up my research and academic data, which occurs via nextcloud, and it also runs a tailscale exit node and pihole. For me, data preservation and reliability is the most important factor. Currently, I have ~10TB of data. I have been reading about the differences between XFS, ZFS, and BTRFS, but am still a bit confused about what might be best for my use case. In brief: Is there any benefit of changing to ZFS in the data drive? This seems to suggest that bitrot protection doesn't happen if using ZFS in the array (but this SpaceinvaderOne video might disagree?), but I don't understand why. If true, it seems like the benefits of ZFS in an array don't apply to my use case. If I do want to change to ZFS or BTRFS in the array, do I just unassign the data drive and then reassign it using ZFS, and it will rebuild from parity? Like the above video, but without the need to reallocate data off the drive first. Am I correct in thinking parity drives insure against drive failure but not data failure, and therefore buying a third drive and using it as second parity drive wouldn't offer any additional data protection. Would this be sensible to do anyway, given I only have 2 drives? Would using ZPool be better than the standard array, as this would provide Bitrot protection? Is converting from the current xfs-with-parity setup to a ZPool doable? Are the difficulties of expanding a ZPool in the future likely to be significant given I'm currently using such large drives? FYI, I also have a second off-site backup running ubuntu. This uses ZFS with two drives, has a nextcloud client, and runs periodic cron jobs to backup the copy of the nextcloud directory.