New ReadyNas 312/314/316?

MSD wrote:

COMPATABILITY CONCERN: If the PRO Series is becoming redundant and the new OS isn't being rolled out to them, I can also see a compatibility issue. Example: Some of my clients have invested in multiple units. If one fails they can currently take the drives from one and then place into another UNIT and away they go. This will no longer be possible if they invest in the Newer Models. The drives in newer model can't be placed into the older should something go astray. In turn they are left with a "mish mash" of NAS technologies.

Though not supported, you can run the new OS on existing systems: http://www.readynas.com/forum/viewtopic.php?f=35&t=70323

So assuming you (or your client) bought one of the new models and it failed out of warranty (some models have a 5 year warranty) and assuming your old Pro was still working then you could install the new OS onto it (use a spare disk) and use it to recover your data. After recovering your data you could downgrade the Pro back to the old OS if you wish (this would also require a factory default after installing the modified firmware image to downgrade).

As for if your Pro fails out of warranty you should be able to check to make sure the ReadyNAS OS device has the latest firmware on it (use a spare disk), then power down, remove the spare disk, migrate your disks across and boot the NAS. Do not do a firmware re-install. The NAS should boot the old OS and you should be able to copy off your data. If you like you could test this using a spare disk (not from your array) moved from a 4.2.x box to a 6.0.x device. Before moving the disks across you could also clone the disks from the failed 4.2.x NAS in case something goes wrong.