snatch1e

As it was said, you may try unRAID which would handle even the different size drives.

As alternative, it looks like mdadm should fit your requirements. You can use smth like openmediavault for that.

I would definitely contact seller for that. Warranty is one of the things why you get the new drive, at least that is critical to me. Return the drive if they would refuse to provide you with the warranty.

Good luck further with your configuration!

Well, same I can tell about you.

i don't have space for disk image by the way.

Get the backup drive for it, make the image and restore after. It's the most efficient way.

Look for the best deals and the best $/TB ratio. Not really much other advices rather than having more backup copies next time.

It is still not only about me. But ok.

You can use FreeFileSync to sync the data across two drives. I wouldn't say that it's a complete backup, but should be enough for your use case.

Well, but if that doesn't happen?

I do prefer pre-built NAS over DIY when it comes for simple and straightforward solution, but it still depends from the use case.

I hope it helps a bit.

Usually enterprise drives have the dwpd in their specs, and consumer grade not likely to have it.

Whatever, just use instead of $ your local currency...

I would use Samsung PM897 rather than 990 pro, simply because PM897 is enterprise drive, and it should be more reliable.

Also, compare both drives DWPD, the higher it is, the more reliable drive is. https://www.kingston.com/en/ssd/dwpd