erasure vs raid

(Taking RAID6 for comparison, because it has dual parity.) RAID6 can protect against 2 drive failure Erasure code can protect disks from multiple drive failures. Particularly for Minio, it N/2 drives can fail and data is still safe.

Minio's erasure code is at object level. For RAID, it is whole volume. Healing can only be performed at volume level. This means huge down time.

Minio can heal one object at a time. Besides, Minio is designed to not heal at all for its life. Just deploy and forget.

Minio also has bitrot protection at object level. It can detect corruption of a block within an object and safely eliminate it. RAID cannot handle these errors at a granular level. It will lead to total volume failure. In layman's terms, RAID is inadequate for today's drive size and data capacity. Erasure code or replication is the way to go.