I had to replace a ZFS pool cache drive. Copying files from the cache to the array would have taken a full day (not an option), so instead I used zpool replace to swap the drive in place. Everything worked perfectly, and the system is running fine.

However, in the UI my new drive is showing as “Cache 3” with the correct details, but it has a blue square icon indicating it’s a “new drive” (not initialized). In reality, it is initialized and working as expected.

@SpaceInvaderOne — this might be a great topic for one of your videos, since I couldn’t find much on replacing cache drives with ZFS directly.

Has anyone run into this before? How can I get the UI to catch up to reality?

Please post the diagnostics with the array started.

Here are my diagnostics. As far as I can tell, Unraid can't tell that the zfs pool is working correctly and the drive is part of it, but parts of the system can tell that.

tower-diagnostics-20250901-1649.zip

This is just a display issue, but reimporting the pool should fix it:

on main click on the first device for that pool and then "remove pool"

back on main, create a new pool with the same name and number of slots

assign the pool device(s), leave the filesystem set to auto

start the array to import the pool

I realize it's a display issue. Deleting the pool sounds insanely dangerous.

My concern is that it should fix it itself by comparing the display information with the pool data on the linux system.

12 hours ago, Edival76 said:

Deleting the pool sounds insanely dangerous.

It's not at all, it will just reimport the pool.