EDIT: I was able to get the bulk of the drives to drop the error, with a stop and start of the array. not sure why. Edit down to the two drives still showing the error, and adding new log.

Thanks in advance to any help provided.

@JorgeB I think we ran into this once before, but I can't find the old thread related to it. Maybe I posted on someone else's thread. Sorry if I am wrong, But you have always been an amazing help to me with these goofy ZFS issues.

ZFS 2-Drive mirror pool.

I am currently replacing some 16TB drives with 18TB drives.

Resilvering has been going for a couple weeks now, slowly but surely.

I just noticed last night that two drives not related to the upgrade were showing a red-flag on the "main" tab, and the error read: Device has an error status: CANT_OPEN

I had to perform a reboot today on the entire server, so while the server was off, I took the change to pull out and put the drives back in, just to make sure that wasn't a connection problem. There was no issue with the shutdown or startup.

Now, more drives that are the new 18TB drives, are showing up as red flag. As well, the resilvering is only showing on a single drive.

Diagnostics attached.

Screens:

server-diagnostics-20260531-1513.zip

UPDATED server-diagnostics-20260531-1532.zip

Edited June 8Jun 8 by shelfactor
new details

To clarify: The two drives with the Red Flag, are two that are not related to the drive replacements.

Sorry for the multiple updates, however, now the red flags have come back to the original big group. Showing them again below with updated logs again.

UPDATED-2 - server-diagnostics-20260531-1610.zip

More information:

The two drives alone (ZR53YVXT & ZR532FCM) have zero read/write occuring on them.

The mentioned group of drives with red flags does.

UPDATE:

All mirror sets have returned to 'resilvering' however the countdown clock is ever increasing the estimated time remaining.

Drives still show red flags.

Edited June 1Jun 1 by shelfactor

@JorgeB I believe my red flag issue may be related to this similar thread... Maybe a bug in 7.3.1?

https://forums.unraid.net/topic/199069-zfs-drive-status-cant-open/

7 hours ago, shelfactor said:

I believe my red flag issue may be related to this similar thread... Maybe a bug in 7.3.1?

I believe so.

@JorgeB Thank you, since it appears the resilvering is moving along now, I will marked this as solved.

I will come back if I run into any further issues.

@JorgeB Found cause for this issue and has created a bug report.

Link to thread comment about what is causing it for me:

https://forums.unraid.net/topic/199210-resilver-vs-remove-mirrors-time-to-scrubreplaceresilver-1month/#findComment-1626731

Marking Solved.