Expanding an array does work but you get less usable space compared to starting a new array from scratch. The old data doesn't get restriped so you get a less efficient parity-to-data ratio, and this effect accumulates as you add more drives.
Iirc cloudflare does this by default
Expanding an array does work but you get less usable space compared to starting a new array from scratch. The old data doesn't get restriped so you get a less efficient parity-to-data ratio, and this effect accumulates as you add more drives.