TerraMaster Official Forum

After a power failure, I restarted my NAS (a F4-210) but could not anymore access the shared folders via SMB, the web interface was not available neither the NAS responded to ping, albeit the LAN light was green and steady.
Pressing the power button did not do anything, so I was forced to unplug the cord to restart again.
Then the web interface displayed the «Loading, checking the file system etc.» message. It went on all the night; the drives LED were blinking orange/green.
Then I accessed the web interface from another PC and could not log in: user ID and password are correct, but do nothing.
The device answers the ping normally, all the LEDs are green and steady but the shared folders are still inaccessible, so I obviously cannot perform any backup of the data.
What should I do? Reinstalling TOS? Thanks in advance.

Please refer to the article to repair the file system.

The device refuses SSH login: PuTTY says «Network error: Connection refused» and the web interface is now totally inaccessible as well (the browser too says «connection refused»). Anyway, the NAS still answers to the ping and le LEDs are all green.
What else should I do? Thanks.

Please refer to the method 2 of the article to reinstall the TOS.

I followed the method 2 up to step 6.
At step 7 the attached web page shows to me: the two clickable buttons have no label, no matter the browser I am using (Opera, Firefox, Edge. IE does not work).
"Fundamentals & Preliminaries" manual does not contain such a picture. Which button must I press?
Thanks.

I was able - apparently - to reinstall TOS, and reached the setup step.
I set device name (SS-MEMO), username and password but the page got stuck after the e-mail verification (anyway, the message was correctly sent).
Now the TNAS PC app correctly finds SS-MEMO but it is «Not initialised» and the web login attempt receives a "bad gateway" answer (see the attached screenshot) in Firefox and an ERR_EMPTY_RESPONSE, then an ERR_CONNECTION_REFUSED in Opera.
Drive LEDs blink gree/orange, with the #1 drive LED more orange than green.

Please try the following steps：
1. Log in to the SSH terminal
2.Restart the nginx service 3.Restart the php service 4. Refresh the page

After a network power failure last night (every cloud has a silver lining...) I was able to complete the setup and the device is now online and the web interface works fine. Nevertheless, I have now the following issue.
Before the reinstallation, I had two volumes:
- a RAID 1 volume on drives 1-2 corresponding to the folder appdata, 87% full;
- a RAID 1 volume on drives 3-4 corresponding to the folder Volume_2, 5%full.
Albeit the disks, after having been removed, were reinserted in the same places, the volumes are now reversed (I can tell from the percentages).
This would not be a problem, but the folder appdata, which I can access to by the File Manager app, is now empty.
If I try to create a new shared folder, the "old" folders appdata and Volume_2 show up (see attached Schermata03.jpg), but it looks they have been placed all on Volume #1, while the former should now be on Volume #2 (87% full).
Should I restore («ripristina», see attached Schermata04.jpg) the Volume_2 folder on Volume #1 and the appdata folder - the original, not the empty one - on Volume #2?
Please feel free to ask if not clear.
Thanks.

POST SCRIPTUM
The original volume:
- on appdata (87% full) had a btrfs file system;
- on Volume_2 (5% full) had a ext4 file system.