[Discuss] SSD drives vs. Mechanical drives

[richard.pieri at gmail.com (Richard Pieri)]

Edward Ned Harvey (blu) wrote:
> Truth is:  Hardware mirroring doesn't provide data integrity.  But

Hardware mirroring = redundant disks, and you just said that I was
incorrect that "redundant disks do not provide data integrity."

No, the fact is that redundant disks DON'T protect your data. Write
holes. Parity corruption. Rebuild errors. Cache inconsistency. These can
eat your data without warning, without notification, all while the
hardware keeps going even after hardware faults.

> software mirroring with btrfs/zfs do indeed provide data integrity.

This isn't the hardware that provides for data integrity. It's the
checksum trees that ensure integrity and replicated data that provides
for accurate rebuild. This is orthogonal to redundant hardware. You can
do this with a single device: data integrity without redundant hardware.

-- 
Rich P.