TerraMaster Forum

Applicable Models:
All TNAS models

“Adding Disks to an Array”
Supported Array Types: TRAID, TRAID+, JBOD, RAID 5, RAID 6.
This operation increases the capacity of an existing array (storage pool) without changing its RAID level.
Steps:
1.Power off the TNAS by briefly pressing the power button. Wait until the power indicator turns off, then insert a new disk into the TNAS. Ensure the new disk’s capacity is equal to or larger than the smallest disk in the array.
2.Power on the TNAS by briefly pressing the power button. Go to Control Panel > Storage Management > Storage Pool > Edit > Add Disk to Array, select the disk, and confirm the settings.
3.Navigate to Control Panel > Storage Management > Volume, click Edit, and adjust the volume capacity as needed.
Note:
Only one disk can be added at a time; adding multiple disks simultaneously is not supported.
If the storage pool/volume does not expand automatically after synchronization, manually expand it by following this guide:
viewtopic.php?t=2342


“Online Array Migration”
Supported Array Types: TRAID, Single, RAID 1, RAID 5.
Upgrades the current array to a higher redundancy level without data loss. Requires adding disks with capacities no smaller than the smallest disk in the existing array.
Migration Order (Mandatory):
Single → RAID 1 → RAID 5 → RAID 6 (no skipping allowed).
RAID 10 cannot be migrated to; it must be created during initial array setup in TOS.


Steps for TRAID → TRAID+ Migration:
Refer to: viewtopic.php?t=6404

Steps for Other Migrations:
1.Power off the TNAS, insert a new disk (capacity ≥ smallest disk in the array), then power it back on.
2.Go to Control Panel > Storage Management > Storage Pool > Edit > Online Migration, select the disk, and confirm.
3.Adjust the volume capacity under Control Panel > Storage Management > Volume > Edit.

"Online Array Expansion"
Supported Array Types: TRAID, TRAID+, RAID 1, RAID 5, RAID 6.
Replaces smaller disks with larger ones without changing the total disk count to increase array capacity.
Steps:
1.Power off the TNAS, remove the disk to be replaced, and insert a larger-capacity disk.
2.Power on the TNAS. A continuous beep will sound, and the Message Center will report array degradation. Mute the buzzer via the TOS desktop sidebar.
3.Go to Control Panel > Storage Management > Storage Pool (shows as degraded) > Edit > Array Expansion, select the new disk, and confirm.
4.For multiple disk replacements, wait for synchronization to complete before repeating Steps 1–3.
5.Adjust the volume capacity under Control Panel > Storage Management > Volume > Edit.

If the pool/volume does not expand after replacing all disks, manually expand it:
viewtopic.php?t=2342

Note:
Array synchronization impacts performance - avoid other operations during this process.

This is exactly what I was looking for, very detailed instructions, thanks!

I currently have an F2-423. I am running TOS 6.0.694. The current storage consists of a 256GB M2 and a 8TB HDD. There are two volumes and two pools. Volume1 is Pool1, the 256GB M2. Volume2 is Pool2, the 8TB HDD. Both drives are formatted as BTRFS. I want to add new 1TB M2 to Volume1 and a new 8TB HDD to Volume2.

Pool1 and Pool2 are currently defined as "single disk". I believe I need to use JBOD to add the new M2 and HDD.

When I look at the Storage Pool edit options, there doesn't seem to be a mechanism to do this. The only selectable option is "On line RAID Level Migration", and that option is described as "single disk to RAID 1, RAID 1 to RAID 5, RAID 5 to RAID 6 and TRAID to TRAID+".

Is there any way to accomplish what I want to do? Do I need to remove the existing volumes and pools and start from a blank slate?

Nikdfish wrote: ↑24 Jun 2025, 08:03

If you need to add one disk and change single disk mode to JBOD, please back up data, delete volume and storage pool, then create JBOD array with disks you need

Thanks for the reply. I thought that might be the case, just wanted to make sure it was the proper way.

I just finished with the process with no error messages. Waiting for Volume2 to show up in file manager.

ETA: Finally realized I needed to add a shared folder to the volume to have it show up...

I have a new F4-425. I added a single 16TB drive and created a single volume TRAID. I’m copying 12 TB data from an old RAID. When the copy is done, I plan to add 10TB, 8TB, and 5TB drives from that old raid to the TRAID (to expand capacity and have parity data). Is this possible? I assumed thi was doable, but I’m not sure now reading this FAQ. Thanks.

ShoutingMan wrote: ↑07 Apr 2026, 01:10

This operation is not feasible. To add a new hard drive, the following two conditions must be met:

1、The drive type must be consistent with the existing disks in the storage pool.
2、The capacity of the new drive must be greater than or equal to the smallest drive currently in the array.

Your current TRAID array consists of only one 16TB drive, which means the minimum drive capacity in the array is 16TB. Therefore, you can only expand the array by adding drives with a capacity of 16TB or larger. It is not possible to add 10TB, 8TB, or 5TB drives directly.

TMnight wrote: ↑07 Apr 2026, 11:41

ShoutingMan wrote: ↑07 Apr 2026, 01:10

This operation is not feasible. To add a new hard drive, the following two conditions must be met:

1、The drive type must be consistent with the existing disks in the storage pool.
2、The capacity of the new drive must be greater than or equal to the smallest drive currently in the array.

Your current TRAID array consists of only one 16TB drive, which means the minimum drive capacity in the array is 16TB. Therefore, you can only expand the array by adding drives with a capacity of 16TB or larger. It is not possible to add 10TB, 8TB, or 5TB drives directly.

Bummer.

If I start over with a 8TB, 10TB, and 16TB at the beginning, will that work?

ShoutingMan wrote: ↑07 Apr 2026, 20:35

That would give you 18TB of USABLE capacity. FYI adding a further 8TB drive would give 26TB. You can check the calculations here:
https://support.terra-master.com/raidca ... n/?lang=en

Gremlin wrote: ↑08 Apr 2026, 00:00

Spot on as always! The 18TB calculation clears things up, and the calculator link is a helpful addition. Thanks for sharing.