Following on from this question: Installing Windows 10 (same product key) on a separate drive in case primary drive fails (multi-boot), I have a 237GB SSD C: drive (almost full, nearly 4 years old) with Windows 10. I have a 1.8TB magnetic drive (D:), currently unused and empty. I want to mirror the C: drive to the D: drive, so if the C: drive blows up, I don't have downtime as I go through a restore process. How do I do this (using Windows 10 or otherwise)? Can I do it by creating a partition on the 1.8TB D: drive so I 'm not wasting all that space? (C: drive is only 237GB.)
Obviously backups are already in place.
Edit: This is not a duplicate of my linked question. They are about completely different things. That question was about installing, not mirroring, Windows 10 on another drive on the same machine using the same product key, which is what I prefer to do. Still waiting for an answer there, please have a crack, I'd really like to know how to do it, and have a bunch of related questions about it. This question is about mirroring an existing C: drive to a second drive (using Windows 10 tools or otherwise), because that was suggested in an answer to the first question, although it didn't actually answer the question.