I've got a fresh TrueNAS MiniXL+ which was delivered a few days ago which was immediately updated to the latest TrueNAS CORE 12, then updated to the latest TrueNAS SCALE before installing drives. 8xTB TOSHIBA_HDWR180 and a 1TB Crucial CT1000BX500SSD1were installed in a RAID-Z2 with L2ARC configuration named pool0. The drives had previously been used in my other NAS for about a year without error, and were replaced only due to upgrading it with 14TB drives. As soon as I enabled apps on the new pool the system would come up with the gui showing the pool as offline. A zpool status would show the pool as unmounted, and a zpool import would attach the pool without error, however apps would not startup. As long as apps are in a failed state it seems like the drive will come up with the pool mounted, but once get apps working again, but unselecting and reselecting the pool in the apps screen the machine comes up with pool0 detached. The pool only contains the system and apps dataset and a readonly dataset for my nextcloud data that is snapshot replication from the other NAS. Nothing is live yet as I've been reluctant to start migrating services to this system with this behavior.