I replaced a SSD drive in the cache pool with a brand new 1tb NVMe. Once Unraid and the array started the NVMe was visible. I assigned it to the cache pool. Checked the box to format the unassigned drive which then displays "formatting". But if I try and go to any other Unraid menu the UI is completely frozen. And when refreshing the web url it just says: ip_address is unreachable. Any ideas or insights will be greatly appreciated. Let me know if you need more details.

I managed to see this in the log before the terminal window also became unresponsive:
Nov 26 15:15:23 Proactive kernel: mdcmd (36): nocheck pause

Nov 26 15:15:24 Proactive emhttpd: creating volume: cache (btrfs)

Nov 26 15:15:24 Proactive emhttpd: writing MBR on device (nvme0n1) with partition 1 offset 2048

Nov 26 15:15:24 Proactive emhttpd: shcmd (270): sfdisk --quiet --label dos /dev/nvme0n1 <<< 'start=2048'

Nov 26 15:15:24 Proactive kernel: nvme0n1: p1

Nov 26 15:15:24 Proactive kernel: nvme0n1: p1

Nov 26 15:15:24 Proactive emhttpd: shcmd (271): udevadm settle

Nov 26 15:15:24 Proactive emhttpd: shcmd (272): /sbin/wipefs -af --lock /dev/nvme0n1p1

Nov 26 15:15:24 Proactive emhttpd: shcmd (273): /sbin/blkdiscard /dev/nvme0n1p1

Nov 26 15:15:55 Proactive kernel: nvme nvme0: I/O tag 64 (5040) opcode 0x9 (I/O Cmd) QID 1 timeout, aborting req_op:DISCARD(3) size:4294966784

Nov 26 15:15:55 Proactive kernel: nvme nvme0: I/O tag 65 (2041) opcode 0x9 (I/O Cmd) QID 1 timeout, aborting req_op:DISCARD(3) size:4294966784

Nov 26 15:15:55 Proactive kernel: nvme nvme0: I/O tag 66 (1042) opcode 0x9 (I/O Cmd) QID 1 timeout, aborting req_op:DISCARD(3) size:4294966784

Nov 26 15:16:25 Proactive kernel: nvme nvme0: I/O tag 10 (c00a) opcode 0xa (Admin Cmd) QID 0 timeout, reset controller

Nov 26 15:19:35 Proactive kernel: nvme nvme0: Device not ready; aborting reset, CSTS=0x1

Nov 26 15:19:35 Proactive kernel: nvme nvme0: Abort status: 0x371

Nov 26 15:19:35 Proactive kernel: nvme nvme0: Abort status: 0x371

Nov 26 15:19:35 Proactive kernel: nvme nvme0: Abort status: 0x371

The device is failing the blkdiscard command. This is a standard command that shoudl be support, but I've seen this before with some no brand devices, which brand/model NVMe are you using?

Thanks for your reply.

It's a Netac NVMe M.2 SSD PCIe Gen3x4 2280 1TB drive. I took my motherboard user guide with to the shop and they assured me it would be fine.

Never heard of it, I woudl recommend using a brand name device, like Samsung, Crucial, WD, etc.

I'm going to return it tomorrow. The guy said its a good brand but I'm also unfamiliar with that brand. Think he was trying to make a quick sale.