3TB Compatibility List

Not yet. Now that 4.2.16 has been released and 3TB support is no longer experimental NetGear probably needs a bit of time to qualify a range of 3TB disks. They need to test a large quantity of disks on a lot of ReadyNAS models and the thorough testing they do does take time.

Is there something like a 3TB compatibility list?

Very good question

They need to test a large quantity of disks on a lot of ReadyNAS models and the thorough testing they do does take time.

Testing that we should expect has been ongoing in parallel with the development of 4.2.16. Otherwise, how did they know 4.2.16 was ready to release?

In fact I'm quite surprised the HCL is not available in parallel with the update announcement - 3TB support is listed as the #1 improvement on the announcement - so let's hope we see this very soon

There is now a 3TB disk on the compatibility list, the HDS723030ALA640.

I expect that while NetGear has been testing 3TB drive support, it may not have been testing all drives models on all NAS models in sufficient quantities to qualify them. I think they'll want a disk model qualified on all suitable x86 models before they add it to the compatibility list for any of them.

Do all the same rules apply regarding sector size? I'm assuming all 3TB drives are 4k.

Yes. All 3TB drives would be 4k sector drives. It wasn't necessary for 2TB drives, but more and more of them use it. Making the change to use the 4k sector size with 2TB drives was good preparation for when it would necessary.

Using 3TB drives also requires GPT partitioning (a new feature added in 4.2.16 to add support for 3TB drives). This irreversible update is automatically made when you update to 4.2.16 regardless of what disks are installed and is the reason why you can't downgrade after updating to 4.2.16.

I only tought they should have tested some drives (shure not only with one) in Beta Testing.
So there should be a list.. perhaps not official, but something like "they've worked in Beta"- list here in the Forum.
Shure better in the official HCL ;-)

mdgm wrote:
Yes. All 3TB drives would be 4k sector drives.

While perhaps not very important as all ReadyNAS now support both 512 and 4K sector drives, that statement might not be correct. It has already been reported that the first 3TB drive released by Seagate (supplied in a USB case) was in fact a 512 byte sector drive.

This might have been important for the NV+/Duo where a factory reset is required to enable 4K sector support (To be clear: x86 based NAS do not require a factory reset for 4K sector support) - but the lack of GPT support on those models means 3TB will not be supported anyway.

chsu83 wrote:
I only tought they should have tested some drives (shure not only with one) in Beta Testing. So there should be a list.. perhaps not official, but something like "they've worked in Beta"- list here in the Forum. Shure better in the official HCL ;-)

They wouldn't have test just one drive in the beta testing. But there are a lot of ReadyNAS models to qualify 3TB drives for. To qualify a 3TB drive they need to test the drive on multiple units of each ReadyNAS model the drive needs to be qualified for and purchase more disks than drive bays to allow for drive failures. This is not only expensive, but also time consuming. Of course as the betas progressed it could well have become clear that changes needed to be made to support some of the drives, making it impossible to qualify them in time for the release of 4.2.16. We users can only speculate as to why only one 3TB drive is on the list at this time. However one should note that NetGear won't put disks on the compatibility list, merely if they have a "gut" feeling that they'll work. They need to pass NetGear's extensive testing.

sphardy wrote:
It has already been reported that the first 3TB drive released by Seagate (supplied in a USB case) was in fact a 512 byte sector drive.

This is interesting. I was under the impression that the reason for 4k sector support in the first place was that it would be needed for all 3TB drives. Do you have a link?

mdgm wrote:
This is interesting. I was under the impression that the reason for 4k sector support in the first place was that it would be needed for all 3TB drives. Do you have a link?

Desired - yes, Needed - No. 4K sectors are to enable increased manufacturability of drives as capacities increase and so sector counts increase. If a HDD manufacturer can reliably & economically produce a 3TB HDD using 512 byte sectors, then why not?

See bottom of this article: http://www.anandtech.com/show/3858/the- ... 3tb-review

Note: This however excludes consideration of any software related dependancies

If I understand correctly from the posts above, 3TB drives will not be supported on the ReadyNAS NV+. Is this correct? I was hoping to upgrade my existing ReadyNAS as the price of these drives dropped.