rn214 increase RAID 5 capacity by installing larger disks.

Once again, I appreciate the insight. I'm afraid I always get Raid 0 and 1 confused. I always think Raid 1 is JBOD, just a bunch of disks concatenated together into a single virtual disk.

If I had the ability to back up 19 TBs I would. I'm just going to have to save the most important stuff and hope for the best.

As to why trust RAID 5, well, that's the point isn't it? I may well be able to afford $1800, but my money is still limited. RAID 5 or RAID 1, either can support a single disk failure. There's double the number of opportunities with RAID 5, but there's also 3/4th of the raw storage of the disks instead of 1/2. IronWolf drives have an MTBF of 1 million hours (114 years) so I don't think it's too much of a risk.

Anyway, I also have a RN104, which is currently stocked with four 4TB drives, or 10.6 TB space which is about 90% full. Because of what you told me, I think I'll copy as much of it as I can to the RN214, back up as much as I can of the rest, and then stick the new disks in it. Same space increase, less risk.

I will take it slow, put one disk in, run the re-sync, and let it stabilize for a week before putting in the next one. At least I can eliminate the intermediate RAID 1 step you mentioned, saving that until I am ready to make the new space into a RAID 5.

Thanks again for your help.