Someone summarized the requirements pretty well:
| Doesn't require all drives to be the same capacity. | ||||
|---|---|---|---|---|
| Ability to add and remove drives without losing integrity, and without having to manually rebuild. | ||||
| Data redundancy, like RAID. | ||||
| Present many drives as one. | ||||
| FreeNAS | JBOD | RAID1 | ||
| openfiler | JBOD | |||