Hi, I have an UnRaid server with 28 3TB drives which are quite old and I would like to migrate the data to a new set of 14 TB drives. All my google searches on upgrading drives seems to suggest I do this one drive at a time. Given the large number of drives and time to re-sync parity etc., Im wondering if it’s possible to have two active arrays at the same time which would allow me to re-create the shares etc., and simply move the data to the new array. Is that possible? If not, what is the best way to accomplish what I’m trying to do? Thank you!

PS - yes, I can connect all the drives (new plus the old) at the same time using SAS JBODS

Edited May 17May 17 by Hammer8

12 hours ago, Hammer8 said:

Im wondering if it’s possible to have two active arrays at the same time

Not in the same server, you can do it with two and then use the LAN to copy the data.

You can use the unassigned devices plugin, remove all the 3TB drives from the array but keep the data, create a new array with the 14TB drives, move all the data from the unassigned 3TB drives to the new array?

Since everything is pooled together the folder structure should remain the same.

3 hours ago, MonadProxy said:

You can use the unassigned devices plugin, remove all the 3TB drives from the array but keep the data, create a new array with the 14TB drives, move all the data from the unassigned 3TB drives to the new array?

Since everything is pooled together the folder structure should remain the same.

Hi, thank you. Would this require the same number of new drives as the number of old drives in the existing array? Unfortunately, I don’t have that many new ones. Just 14 14TB new drives vs. 28 3TB in the existing array.

4 minutes ago, Hammer8 said:

Would this require the same number of new drives as the number of old drives in the existing array?

No.. the idea is to copy the files into the new array you will have setup using the 14TB drives. The files will end up distributed across the drives according to the share settings you have setup using.

The possible downside is that you will not be protected against one of the old drives failing before you have managed to copy the data back to your new array.

Thanks…so

1) unassign all the existing drives from the current array

2) create a new array with the new drives

3) manually copy all the files from each of the old drives to the new array?

Given the current array is redundant, and hence have multiple copies of the same files, if I copy each drive over, would I be creating duplicates of each of the existing duplicate? I’m assuming once I unassign the drives from the existing array, I’ll need to access them as individual drives and not as a whole, but maybe that’s incorrect?

1. Add new disks to the system, mount them with the Unassigned Devices plugin.

2. Format disks and copy (not move) all data from array disks to the unassigned devices plugin. I would suggest using another plugin for this called "Unbalanced"

3. Remove all disks from array, run a new config, and assign new disks (that contain the copied data) to the disk slots.

4. Build parity if you are going to have parity.

I think this way might be a good approach because your old array disks will still contain data in the even you need to add them back in in-case of a new disk failure before the new parity is finished syncing.

Edited May 18May 18 by MowMdown

Thank you…just out of curiosity, why is UnRaid limited to only one array, but can have multiple additional pools?

24 minutes ago, Hammer8 said:

Thank you…just out of curiosity, why is UnRaid limited to only one array, but can have multiple additional pools?

Historical. Originally Unraid had no pools. They have then been added over time.

At first it was to support the 'caching' capability, and then to act primarily as an application drive with better performance than the main array. More recently ZFS support was added for even better performance and the need to have the main Unraid array made no longer mandatory. Support for multiple Unraid type arrays is a roadmap item (and then they will probably be treated just like any other pool).