In reply to a post by Banger:

What the heck do you use all that storage for? I get away with a 1TB NVME and a couple of 500GB spinners for data and a 500GB spinner and portable SSD 1TB for backups.

It will be for video storage and stuff like that

In reply to a post by MilesR:

You live and learn!

Just make sure you also have backups of your data. I can't recall where I kept reading this: "RAID is not a backup" (probably QNAP forums).

As has been mentioned, the rebuild times for RAID5 arrays can be some time, but in a 4 drive configuration offers a decent mix of storage and redundancy.

That is the only problem, large drives mean you need more large drives for back up, as you said, raid is not a backup

I bought a new Synology NAS recently and have repurposed the old NAS as a backup of the primary one using Hyperbackup. Most of the time it is off, just waking up to do the backup. RAID 5 on the main NAS, JBOD on the secondary.

It's not perfect, and no good in case of - say - a fire, but none of the data is business critical. Anything really important is backed up to the cloud.

Sounds ok to me.

I've got a RPi4 with 2 x USB3 drives plugged into it as my backup (bi-weekly rsync job), but like you I have the really important stuff in the cloud.

I've just remembered that the photos are also duplicated onto a drive in the desktop PC (mainly used by my wife) 🙂