RN626X - order for adding disks when 2 of the 6 disks are larger than the other 4

[Deal]

I don't know if X-RAID on OS6 has a limitation in how disks of different capacities are added to a volume. So I have a basic question about adding disks to the RN626X on OS6.

I will have a total of 6 disks to install in the RN626X -- 2x12TB disks and 4x10TB disks. Currently I only have 2 of the 4x10TB disks and both 12TB disks, but I want to get started setting up the RN626X.

A few options occurred to me but I cannot determine from the SW Manual which options will work and still use the full capacity of each disk:

Option 1: Install the 2x12TB disks first. Setup the NAS and install the 4 remaining 10TB disks when they arrive

Option 2: Install the 2x10TB disks first. Setup the NAS. Then when I receive the 2 additional 10TB disks I bought, install them and the 2x12TB disks at the same time.

Option 3 (not desirable): Wait until I receive the 2x10TB disks I've purchased, then install all six drives in the NAS at once. Setup the NAS.

Which of the first 2 options will work with no capacity penalties?

Thanks,

David

[StephenB · Accepted solution]

Install the smallest disks (2x10TB disks) first.

If you install the 2x12TB disks first you won't be able to add the 10 TB drives later.

[StephenB · Accepted solution]

Install the smallest disks (2x10TB disks) first.

If you install the 2x12TB disks first you won't be able to add the 10 TB drives later.

[Deal]

This confirms what I thought would happen. I had hoped that they'd removed that limitation in OS6. Thanks!

[Sandshark]

The way they vertically expand the volume, this limitation will never go away.  It's not much of a limitation when you consider that the ability do do expansion with different sized drives at all is a feature many systems lack.

If you install the 10TB first, it will create a RAID1 of 10TB.  When you add the 12TB, it will expand the 10TB "layer" to RAID5 with 10TB from each of the 12's and add a 2TB RAID1 layer on top with the remainder.  If you start with 12TB's, it cannot expand that first layer because the new drives are too small.

It is possible to get around this manually via SSH, but creating a system that will do so automatically and still allow for future expansion is not easy without building in some limitations.