Good morning,

I have been running ZFS on my unraid server for some time without issue until I managed to mess it up. One of my drives was throwing errors so I replaced the 10TB with a 14TB drive without issue. A couple of months later I noticed that the formatting of the 14TB drive was a 512b vs the others at 4k. I forced a format to 4k and then replaced the "old" drive with the "new" drive. Now the GUI shows Unmountable: unsupported or no file system. I've tried doing a new config and slotting all of the zfs drives and leaving the file system on auto as well as specifying zfs raidz2 without luck. I was playing with a L2ARC special drive, adding it back manually does not fix the issue.

Sorry for the long winded explanation, here is my diagnostic log, the zfs pool is "zfs" and my other pools are running fine. Of note, I can import the zfs pool without issue, the GUI just doesn't seem to like it. I am running the ZFS master program.

Thanks so much for the help.

harley-diagnostics-20250924-0634.zip

Edited September 25, 2025Sep 25 by custom90gt

Pool includes a cache vdev, so it needs to be assigned together with the other devices.

Sep 24 06:34:06 Harley emhttpd: NAME STATE READ WRITE CKSUM

Sep 24 06:34:06 Harley emhttpd: zfs ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: raidz2-0 ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: /dev/sdg1 ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: /dev/sdf1 ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: /dev/sde1 ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: /dev/sdd1 ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: /dev/sdc1 ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: /dev/sdb1 ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: /dev/sdi1 ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: /dev/sdh1 ONLINE 0 0 0

Sep 24 06:34:06 Harley emhttpd: cache

Sep 24 06:34:06 Harley emhttpd: /dev/nvme2n1p1 ONLINE 0 0 0

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 9 slots

assign all the pool devices, including the cache vdev, leave the filesystem set to auto

start the array to import the pool, post new diags if it still fails

That was it, I was thinking I would have to add the cache to the sub pool later on, but adding all 9 disks solved the issue. Thanks