TerraMaster Forum

In my F2-221, HDD1 has failed. I would like to install same sized HDD from my F2-223 into the F2-221 as HDD1. When I physically install the HD, i can see it in the Storage Manager --> Hard Drive as Good. Storage Manager --> Storage Pool shows Pool1 (the only pool) as "Hard drive is missing". If i attempt to edit Pool1, i get the option to Repair RAID. If I click next a couple times, I am able to see the new HD and can select it. However, after I select it and Confirm, nothing happens. I still see the "Hard Drive is missing" error on the pool. Not sure why this is happening. Pls help.

I will format the new HDD on my PC and then try again.

TOS version is 4.2.44-
I tried installing 5.0.176 but the install fails (hangs after it starts unzipping the downloaded bz2 file).

gosavip wrote: ↑15 Aug 2026, 16:13

Since this drive was previously used in an F2-223, residual RAID superblocks, partition tables, or LVM signatures might cause the repair to fail. Please use a disk tool on your PC (such as DiskGenius) to completely wipe it before retrying. We look forward to your update!

Regarding the system update: When running TOS 4.2.44, you cannot directly upgrade to TOS 5.0 using the standard update method. Please follow the required upgrade path and instructions outlined in this guide.

Upgraded the F2-221 to 5.1.67. Did not upgrade further because my / volume is 1.84 GB. I would rather fix the second drive first and then come back to upgrading to TOS 6.0.

I formatted the other drive to NTFS on my PC and inserted it back in F2-221 as HDD1. It appears Normal in Hard Drive. Storage pool is still degraded and when I attempt to add this drive to it, I am able to confirm all the way till the end. After the final Confirm, the button briefly flashes to "Configuring..." before coming back to Confirm. Nothing is happening.

Both HDDs are 4TB.

gosavip wrote: ↑16 Aug 2026, 07:31

To pinpoint the issue, please make sure the newly installed drive is in the NAS, then go to TOS System Interface > Technical Support (Support & Help) > Issue Feedback to generate and download the system report, and send it to our technical support email at [email protected], along with the forum link and your forum ID.

gosavip wrote: ↑16 Aug 2026, 07:31

When experiencing trouble with a reported "good" drive I have found it best NOT to format the drive. Rather, delete all data off the drive and ensure there are no remnants of previous system information remaining. There are a couple of ways "to be sure";
A complete drive "wipe" or security erase (writing 1's and/or 0's to every bit). This can be a long process even with a relatively small drive.
If you have the software (Third party partition managers for example, I just don't trust Windows!) I have found that this works:
(i) Delete all partitions
(ii) Convert drive to MBR format
(iii) Convert back to GPT format
Done
(FYI, I have bought most of my drives off ebay and re-built/installed TOS many times. Since adopting the second method I have never had an issue related to the drives.)

Thanks Gremlin, but that did not work.
I used Windows still to make the change. Will try with Acronis.

gosavip wrote: ↑17 Aug 2026, 01:41

To save you time from trying other third-party tools, please contact our online support team via the link below to schedule a remote technical support session. Our engineers will connect and inspect the drive state directly to assist you with completing the RAID rebuild safely:
https://salesiq.zohopublic.com/signatur ... 97d0be8892

Just curious - is the replacement drive the same make/mnfr/size as the defective drive. (Sometimes different model drives can have different actual size even if the nominal size is the same.)

It is not the same manufacturer but the same size down to the byte. I gave up after a while and will change my F2-223 as my primary NAS and the F2-221 as a secondary degraded NAS. I had puchsed 4 GB WD NAS drives for $63 each after tax in 2023. Now they are too expensive.

EriChan wrote: ↑15 Aug 2026, 22:00

EriChan i upgraded my F2-221 to 5.0.176 and then to 5.1.67. How do i go to TOS 6.0 from here? I tried going to 5.1.145 but I get a "Failed to Update" error upgrading to 5.1.145. I also tried updating to 6.0.53, and that failed too.

My BIOS version is MAPL0304V17, which is supported per the documentation.