Split a regular HDD disk: 1 pancake = 1 partition. Really?

Question

Iron

Hello.
1. There is a regular HDD (from 2 or more pancakes).
It is necessary to make similarity of Raid1 ("mirrors") in one case.
So that if one pancake is damaged, information can be read from the other.
How to implement and is it realistic?
2. Can this be done with an SSD? (so that when one memory module comes out, others would keep a copy in a 50/50 ratio)
In advance, many thanks to everyone for the answers.

Answer 1

High-level means is impossible. Because of logical addressing (LBA), you can't know which pancake your partition is on.
You can try to select experimentally for each disk, and up to the copy.
Or stupidly turn off one of the pancakes altogether.
For SSD, everything is the same, only the controller algorithm can be even smarter due to compression or encryption.

Answer 2

The title doesn't match the subject of the question.
If desired, RAID1 can be raised programmatically.
PS The division into pancakes is utter nonsense.
If you cannot afford to buy a second disk for a normal RAID1, then these data are of no value.

Answer 3

Two pancakes, two sides on each, 4 heads.
But here are the mechanical holders on which the heads are located - 3.
And to speed up the work, the 2nd and 3rd surfaces are immediately used in series.
Therefore, for your idea, you will either have to reflash the disk controller. But doing a raid like this is completely pointless, because it is not the platters themselves that are damaged in the first place, but the mechanics and electronics of the disk as a whole.
And also read here, I once wrote: https://geektimes.ru/post/276014/

Answer 4

You need to learn the materiel ' damn where they teach you :-)