Triple RAID1

I just ordered a new T630. It had been a while since I had to order a new server, so I fell back on my old RAID1/RAID5 plan. Despite the fact that drives have come down in price, I could not quite push my client (cost-wise) to RAID10. So now I have OS RAID1 and data RAID5 (three drives).

That is not a bad solution, but reflecting now upon the fact that I ordered drives sized that even RAID 1 would provide plenty of data storage, I wonder if I would be better off with RAID1 + host spare.

• Would RAID1 be preferable to RAID5 to simply recovery in case of failure?
• Is it possible to convert my RAID5 to RAID1? I assume RAID1 with HS.
• How? Shortcut to a Dell-specific instruction URL would be helpful. It is probably in the pre-boot utilities somewhere; however, if there is a Windows option, that would make life even simpler.

And, while I am at it, is there any such thing as three-way RAID1 to allow double-redundancy?