Questions prior to purchasing the TS-664

English
1

Hello,
I’m considering purchasing the TS-664 to replace my aging and no longer supported Drobo.
Mainly to serve as a Plex server.
I currently have in the Drobo four 8TB drives and one 6TB drive.
I’m fully aware that all the data on these drives will have to be erased when installed in the new QNAP device.

However, if I utilize RAID 5 for these 5 drives, I understand that the RAID will regard all the drives as the smallest 6TB drive when building the RAID yielding a total of 24TB.

However down the road can I replace the single older 6TB drive twith a 8TB drive? If so, when doing so, will the RAID capacity grow to 32TB? Without losing the data in the pool/volume(s)?

Or does this require reformatting the whole array thus losing the data?

Also, if I start the RAID with only 5 bays populated, can I add another drive in the 6th bay later without losing data on the RAID pool/volume(s) increasing the volume to 40TB without losing data on the pool/volume(s)?

Also, if I add M.2 NVME, how do I configure in the OS using this NVME(s) as cache for read/write?

2

All these answers are for QTS (this NAS can also use QuTS, so be aware)

Yes, you can swap the smaller drives and expand capacity later
Yes, you can add disks to an existing RAID5 or 6
You can install two NVMe drives for the system volume, but forget about cache (it does not work on QTS and even if it did work, most people do not use their NAS in a way that cache would help)
Also the OS is always on all internal drives, so as soon as you add spinning disks to the NAS, the OS will be on those as well.

++ Make sure you have backups, a RAID is NOT a backup

3

Thanks you very much. Very helpful!

So what are the M.2 NVME’s typically used for? Another faster RAID pool? in same enclosure?

4

As the system volume
Speeding up your Apps (that where the default installation target for apps is)
Fast IO storage for containers, VM’s
Dedupe scrubber storage (this one really wears down your TBW, so watch out)
etc

5

But don’t confuse “system volume” with OS. It is an easy thing to do. Dolbyman is correct - the OS is loaded across all drives. The system volume is the place where default folders are created (homes, MultiMedia, Photos, Public, etc). And where apps are installed by default.

6

Hello,
If you want to know how to replace your disks one by one, please refer to this article. It can help you replace your disks.

How can I expand the Storage Pool/Static Volume by replacing the disks with larger capacity drives? | QNAP

7

Honestly, I don’t think that’s a good idea. Swapping out the drives one by one means you’re basically triggering a rebuild every time you add a new disk. From a risk standpoint, that leaves your system unprotected for a long time, and performance will take a big hit the entire time too…
If it were me, I’d rather just back everything up, format the system, set up the new RAID from scratch, and then copy the data back. And you’ll be up and running more cleanly that way.