Migrate from multi HDD JBOD RAID to single HDD

[FideSS]

Hello, 

My Xpenology skills have increased quite a lot. I'm now running three different Xpenology boxes (mostly the AI models), and have been able to make Nvidia GPUs work well. 

I have a box right now that I built with a bunch of old laptop HDDs adding up to 3TB alltogether. The other day I managed to get a 3TB regular sized HDD, and would like to migrate my system off of the original disks to this single larger disk. 
I've read tutorial after tutorial but none apply specifically to my scenario or to the JBOD. I've heard about backing up the data from the drives to an external then using Hyper Backup to back up the rest, and I've done that. I'm worried it won't cleanly back up all of my settings. 
I've also heard about removing one drive and replacing it with the new one but didn't think it applies to my situation. 

What is the best way to do this? 

Also, whats to stop me from adding the new drive and making it a hot spare then yanking the old drives out?

Thank you for bearing with my storage ignorance. You guys have taught me so much. 

 

[Trabalhador Anonimo]

It depends on what exactly you want. How many of this old HDD you have. This "regular size 3TB" had drive cam be used, but you will not have security: if it fail, your data will be lost.

If you set this 3TB HDD into a pool with all others HDD, the system will split this big HDD into smaller size as your smaller HDD. Like if your smaller is 500GB, it will split the 3Tb into 5x 500GB partitions and use it to store data and you wont be able to set a hot spare unless you get a new 3TB HDD, because hot spare need to be equal or bigger than your bigger HDD on the pool.

 

[FideSS]

I see. It’s 3 older (potentially unreliable) laptop sized HDDs of 1TB each and one new full size HDD. 
Is there a way to make the full size HDD the main and the 3 crappy ones the backup?

[FideSS]

This is a testing server so I don’t necessarily mind losing the data btw. I have my main that has much larger storage for backups, this is security footage only. 

[Trabalhador Anonimo]

You have to create a pool and a volume, without raid, with 3TB HDD and a another pool, and volume, with smallest HDD and use a backup software to both volumes.

[FideSS]

I'm trying to understand your instructions but the English makes it unclear. 
So I attach the 3TB, add it into a storage pool then create a volume on it. 
I have Hyper Backup backups of the currently running server right now along with a backup of the files on the RAID, but what I want is to maintain all of my settings and containers etc as completely as possible - what backup method is suggested for this, step by step?

[Trabalhador Anonimo]

Pool 1 + Volume 1 -> HDD 3TB, no raid

Pool 2 + Volume 2 -> old laptop HDDs + hot spare if possible

If you use "shared folder" as connection from computer to NAS, you can use Hyper Backup to sync both volumes.

If you use "LUN + iSCSI" as connection from computer to NAS, you should use any backup software to sync both volumes (Hyper Backup does not work with LUNs). As I want to keep everything controlled by my Windows server, I use iSCSI to connect to NAS, so, I use robocopy to sync all things. I had created a schedule task, on server, to run robocopy 3x a day.

 

 

[FideSS]

I’m going to try it as soon as I come back from the trip that I’m on. 
 

Thank you so much for helping. 

[DSfuchs]

On 10/28/2025 at 4:44 AM, FideSS said:

I'm worried it won't cleanly back up all of my settings

Your concern is valid. None of Synology's backup options back up everything. Once all software packages have been stopped and the shares have been moved to a volume2 with share backup2, I back up the remaining portion of volume1 using the Linux tar command via ssh-terminal as root from the root directory, for example:

tar -capf /volume2/backup2/volume1.tgz volume1

Afterward, the Synology should be shut down to remove the old hard drives. It should then boot from the hard drive containing volume2. Then, while the system is running, the new hard drive should be added and volume1 recreated.

The backup is then restored to an empty volume1 as root in the root directory:

tar -xpf /volume2/backup2/volume1.tgz
Finally, the shares should be moved back and all software packages restarted.

 

In addition to the shares, don't forget to also switch the user home directories back and forth to volume2 via the control panel.

 

This works best with two empty, new drives. Otherwise, you'll need to create a new volume3 from the old drives as before, where you temporarily store everything. Then, create volume1 from the hard drive containing volume2, as desired.

Edited Thursday at 07:39 PM by DSfuchs