[georgyo]

Agreed, raid is not backup.

But restoring 50TB of data from actual backups take a lot of time.

I like BTRFS to a fair degree, but thae fact that _any_ two drives failing in its "raid 10" configuration causes data loss is not obvious or intuitive.

[28304283409234]

If one has 50TB(!!) of mission critical data, one should not store it on one machine running btrfs. That is just silly. No many how many mirrors you throw at it.