Hi All,

I'm trying to figure out how to get my zfs pool back online. 2way mirrors.

Started as 12x 2-way mirrors, then just earlier today, I added 3x 2-way mirrors to the pool.

They were added correctly, and everything was fine, until a power issue caused those 6 drives to cause errors.

I was able to successfully complete 'zpool remove (name) (mirror-set-name) on the 3 new mirror sets. ** But the slots were still present on the unraid pool page.

During me trying to get those drives out of the pool, I removed the pool from unraid.. I tried to re-add it with the original 24 drives (12 mirror pools), but I am not getting the error "Unmountable Unsupported or no file system.

No Data had been written to the "3 new mirror sets" and as I mentioned, they were removed successfully and quickly.

Attached diagnostics.

Thank you to all that can help!

nucserver-diagnostics-20250523-2249.zip

Edited May 24, 20251 yr by shelfactor

That pool will most likely need to be destroyed and recreated, but you can try to force import, if it works there could be some data loss, typically the last few seconds or a minute of writes:

zpool import -F space

8 hours ago, JorgeB said:

That pool will most likely need to be destroyed and recreated, but you can try to force import, if it works there could be some data loss, typically the last few seconds or a minute of writes:

zpool import -F space

As always Thank you @JorgeB you're the best.

I too have been thinking that the pool is lost.

When I try the above I get:

16 hours ago, shelfactor said:

that the pool is lost

I think so, best to destroy and restore from a backup, if there's no backup and important data, a data recovery app may help.

@JorgeB Thanks for the input! Backup data restored my pool with zero issue. This one was a fun experiment for me, but I am still unclear as to what corrupted the data.

By chance, are you able to comment on if this process can be used successfully with Unraid (in version 7+)

https://openzfs.github.io/openzfs-docs/man/master/8/zpool-remove.8.html

I have a few other commented threads you've been on, about it working. Maybe I messed up the stages of removing the mirrors, stopping pool, and restarting pool.

**** Recovery Notes ***

Also, for any others coming here later. I did run Klennet ZFS recovery on this pool, as I was always curious how well a ZFS pool could be recovered. Due note, that my data is pretty static, media files. Thus the datasets don't change much.

The software found 100% of my data and from what I tested (verified checksums) and copied off & re-hashed, everything could be recovered.

24 minutes ago, shelfactor said:

By chance, are you able to comment on if this process can be used successfully with Unraid (in version 7+)

You can use it in some circumstances with the CLI:

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/4/#findComment-1512308