TerraMaster Forum

Posted: **23 Feb 2026, 22:56**

Hello all,

I'm using an F4-SSD.
I recently faced an issue with TOS 6 which now refuses to boot.
The NAS doesn't initialize network and therefore is not accessible with TNAS PC for re-install/repair
2x SSD M.2 are fitted in the slots 1 and 2.
When I connect the HDMI output and turn on the NAS, I see the error message :
"Invalid magic number"
When push the reset button while power up the NAS, I hear only one bip and see the error message :
"premature end of file /boot/bzImage"
The only way to connect to TNAS PC is by removing the 2x SSD and power-up. I see then on the TOS interface than is saying "No discs is detected". I tried to plug-in the SSD while the NAS is ON but it is still saying than no disk is detected. I see than this procedure corresponds to the "Method B" but I don't feel confortable to plug M2 SSD while NAS is ON. Is it something safe ? Could please tell me what is the procedure to repair TOS 6 in my situation ?

Thank you.

Posted: **24 Feb 2026, 10:12**

The F4 SSD has a reset button located on its interface. You can follow the steps below to reinitialize the device.
When the device is powered off, use a pin to continuously press and hold the RESET button on the back of the product. While keeping the RESET button pressed, briefly press the power button to start the device. Wait for approximately 30 seconds until you hear three consecutive "beep beep beep" sounds, then release the pin. Next, use the TNAS PC client software to perform a new search for the TNAS device and follow the client's instructions to restart the TOS system initialization process.

Posted: **24 Feb 2026, 10:14**

flo0306 wrote: ↑23 Feb 2026, 22:56

Regarding Method B, please note that while standard HDDs can be used, M.2 NVMe SSDs do not support hot-swapping while the device is powered on. Attempting to do so may result in disk errors or data damage; please strictly avoid this operation.

To assist you further, could you please confirm the following:
Was TOS previously installed on your device?
When all SSDs are installed and the device is powered on, do you hear three consecutive beeps (Beep—Beep—Beep)?

Based on your situation, please refer to this guide for system installation on SSD series products:
viewtopic.php?t=6810

If the disks cannot be detected during installation, the SSD itself may be faulty. We recommend:
Testing the SSD on another device to see if it can be recognized.
Or trying again with a known-working SSD.

Additional Note:
If the device emits only a single "beep" after powering on, it typically indicates an issue with the built-in USB boot drive (located inside the unit). You may follow the link below to recreate the boot drive and then proceed with the installation guide mentioned above:
viewtopic.php?t=6433

Posted: **24 Feb 2026, 16:54**

GevinKe wrote: ↑24 Feb 2026, 10:14
flo0306 wrote: ↑23 Feb 2026, 22:56
Regarding Method B, please note that while standard HDDs can be used, M.2 NVMe SSDs do not support hot-swapping while the device is powered on. Attempting to do so may result in disk errors or data damage; please strictly avoid this operation.

To assist you further, could you please confirm the following:
Was TOS previously installed on your device?
When all SSDs are installed and the device is powered on, do you hear three consecutive beeps (Beep—Beep—Beep)?

Based on your situation, please refer to this guide for system installation on SSD series products:
viewtopic.php?t=6810

If the disks cannot be detected during installation, the SSD itself may be faulty. We recommend:
Testing the SSD on another device to see if it can be recognized.
Or trying again with a known-working SSD.

Additional Note:
If the device emits only a single "beep" after powering on, it typically indicates an issue with the built-in USB boot drive (located inside the unit). You may follow the link below to recreate the boot drive and then proceed with the installation guide mentioned above:
viewtopic.php?t=6433

Hello,

Was TOS previously installed on your device? : NAS was bought on Nov 25 : It was TOS 6 (with last updates)
When all SSDs are installed and the device is powered on, do you hear three consecutive beeps (Beep—Beep—Beep)? No, I only hear three consecutives beep when I remove the 2 SSD. I can access to TOS through the browser and the IP address but I have the message than no disk is detected (expected as no SSD is mounted). As the NAS is able to connect and boot without SSD and is detectable from TNAS PC, are you sure the USB boot drive is corrupted ?

As mentionned in my previous message, when my 2 SSD are mounted I have 2 different error messages than I can see through NAS HDMI :
- When I only power on the NAS normally : "Booting from RAID system : Error Invalid magic number : Failed to boot both default and fallback entries"
- When I press the reset button and power ON the NAS (only one beep even after 30s) : "Booting from RAID System : Error premature end of file /boot/bzImage"

Posted: **24 Feb 2026, 22:10**

flo0306 wrote: ↑24 Feb 2026, 16:54

Based on your description, this appears to be a composite issue:

USB Boot Drive is Functional: The fact that the NAS can boot and emit three beeps without disks proves that the internal USB boot drive is functioning correctly.
Corrupted SSD System Kernel: The error messages "Invalid magic number" and "premature end of file /boot/bzImage" clearly indicate that the TOS system kernel files on your M.2 SSDs are corrupted. This causes the boot process to hang, prevents network initialization, and stops TNAS PC from detecting the device for recovery.

Repair Steps
Step 1: Environment Preparation
1. Power off the NAS and remove all M.2 SSDs.
2. Boot the NAS without disks. Confirm that it emits three beeps and can be detected by TNAS PC. This confirms the boot environment is healthy.

Step 2: Format the SSD System Partitions
You will need a USB-to-M.2 NVMe enclosure and a computer.
1. Connect the SSD to your computer using the enclosure.
2. Use a disk utility (such as DiskGenius). Format out ONLY the second partition (approx. 7.6GB, which is the TOS system partition). DO NOT touch the larger data partitions, or you will lose your data. ()
3. Repeat this for the other SSD.

Step 3: Reinstall TOS 6
1. Power off the NAS and reinstall both SSDs (with the system partitions now cleared) into their slots.
2. Power on the NAS. The system should now boot from the USB drive and enter the initialization interface since no valid system is detected on the SSDs.
3. Use TNAS PC to locate the device and follow the wizard to complete a fresh installation of TOS 6.

Step 4: Mount Data
After installation, go to Control Panel > Storage Management to check if your original Storage Pool/Volume appears, and mount it to access your data.

If the problem persists: You may try re-creating the USB boot drive (refer to: viewtopic.php?t=6433) before repeating Step 3.

Posted: **25 Feb 2026, 01:54**

GevinKe wrote: ↑24 Feb 2026, 22:10

2. Use a disk utility (such as DiskGenius). Formatted out ONLY the first partition (approx. 7.6GB, which is the TOS system partition).

On my systems the o/s partition is actually the SECOND partition.

Posted: **25 Feb 2026, 11:02**

Gremlin wrote: ↑25 Feb 2026, 01:54
GevinKe wrote: ↑24 Feb 2026, 22:10

2. Use a disk utility (such as DiskGenius). Delete ONLY the first partition (approx. 7.6GB, which is the TOS system partition).
On my systems the o/s partition is actually the SECOND partition.

Sorry, we made a mistake. You are right, it should be the second partition.

Posted: **26 Feb 2026, 16:30**

Thank you ! I successfully deleted the second partition and now the NAS is booting correctly. To not loose my data, should I go through the automatic intallation (it is mentioned that disks will be initialised and data erased) or should I select the manual installation by pressing ESC key and selecting manually the bootloader file ?

Posted: **26 Feb 2026, 17:53**

flo0306 wrote: ↑26 Feb 2026, 16:30 Thank you ! I successfully deleted the second partition and now the NAS is booting correctly. To not loose my data, should I go through the automatic intallation (it is mentioned that disks will be initialised and data erased) or should I select the manual installation by pressing ESC key and selecting manually the bootloader file ?

For your F4 SSD (TOS6)
When prompted with 'The disk will be initialized and data will be erased', please do not continue with the operation, as this will result in data loss on the SSD.
Please log in to the SSH terminal (via tools such as PuTTY), locate the SSD missing the second partition, which is named sdz? (sdza, sdzb, sdzc, sdzd). Manually recreate the second partition for these SSDs:

Code: Select all

parted -s /dev/sdz? mkpart primary 300 8492

Clear temporary files:

Code: Select all

rm /tmp/slave*

Clear the browser cache and refresh.
After this, the prompt 'The disk will be initialized and data will be erased' should no longer appear.

Posted: **26 Feb 2026, 19:07**

TMzethar wrote: ↑26 Feb 2026, 17:53
flo0306 wrote: ↑26 Feb 2026, 16:30 Thank you ! I successfully deleted the second partition and now the NAS is booting correctly. To not loose my data, should I go through the automatic intallation (it is mentioned that disks will be initialised and data erased) or should I select the manual installation by pressing ESC key and selecting manually the bootloader file ?
For your F4 SSD (TOS6)
When prompted with 'The disk will be initialized and data will be erased', please do not continue with the operation, as this will result in data loss on the SSD.
Please log in to the SSH terminal (via tools such as PuTTY), locate the SSD missing the second partition, which is named sdz? (sdza, sdzb, sdzc, sdzd). Manually recreate the second partition for these SSDs:
Code: Select all
parted -s /dev/sdz? mkpart primary 300 8492
Clear temporary files:
Code: Select all
rm /tmp/slave*
Clear the browser cache and refresh.
After this, the prompt 'The disk will be initialized and data will be erased' should no longer appear.

Hello,

@Mac ~ % ssh [email protected]
ssh: connect to host 192.168.1.118 port 22: Connection refused

It seems SSH is not activated. I can ping the NAS on the IP.

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