I recently added a spare NVME drive to my unraid server using a PCIE adapter. It shows up correctly and i'm able to add it to the cache pool, but it says: Unmountable: Unsupported partition layout. I have the option to format, but when i try to do this, the status doesn't change. I checked the disk log and I'm getting some MBR errors:

 

Oct 12 00:05:47 Tower kernel: nvme0n1: p1
Oct 12 00:05:47 Tower root: /dev/nvme0n1: 8 bytes were erased at offset 0x00000200 (gpt): 45 46 49 20 50 41 52 54
Oct 12 00:05:47 Tower root: /dev/nvme0n1: 8 bytes were erased at offset 0xe8e0db5e00 (gpt): 45 46 49 20 50 41 52 54
Oct 12 00:05:47 Tower root: /dev/nvme0n1: 2 bytes were erased at offset 0x000001fe (PMBR): 55 aa
Oct 12 00:05:47 Tower root: /dev/nvme0n1: calling ioctl to re-read partition table: Success
Oct 12 00:05:47 Tower kernel: nvme0n1: p1
Oct 12 00:05:47 Tower  emhttpd: writing MBR on disk (nvme0n1) with partition 1 offset 2048, erased: 0
Oct 12 00:05:47 Tower  emhttpd: error: mkmbr, 2187: Input/output error (5): write: /dev/nvme0n1
Oct 12 00:05:47 Tower kernel: nvme0n1: I/O Cmd(0x1) @ LBA 0, 8 blocks, I/O Error (sct 0x0 / sc 0x4) MORE 
Oct 12 00:05:47 Tower kernel: I/O error, dev nvme0n1, sector 0 op 0x1:(WRITE) flags 0x800 phys_seg 1 prio class 0
Oct 12 00:05:47 Tower kernel: Buffer I/O error on dev nvme0n1, logical block 0, lost async page write

 

The drive worked fine when it was in my pc, and the smart report I generated came back with no errors. The drive is still formatted as NTFS with my old data on it (that i've already moved).

2 hours ago, toasty_tt said:

Oct 12 00:05:47 Tower  emhttpd: error: mkmbr, 2187: Input/output error (5): write: /dev/nvme0n1

This is a device error, you can try:

first reboot, then wipe it  with

blkdiscard -f /dev/nvme0n1

then try again to format

Oh thanks for this solution, I've been getting similar issue where I replaced/upgraded my NVME cache with a larger drive, and reassigned the existing cache disk to an Unassigned disk. As a result, for some reason the "old" cache disk (now 2nd NVME) would show up with the option to FORMAT, but after that would only present the option to Preclear, which I did, but then I cannot utilise it as an Unassigned disk because the MOUNT option never becomes usable:

 

After formatting it and Preclearing it a few times, nothing seemed to be working.

I also cleared the disk a few times, deleting all partitions.

After clearing the disk a final time and performing a full system reboot, it seemed to become usable again:

 

Seems like a odd bug somewhere, maybe?

Hi,

I've tried the command you've given me, and then rebooting, however, I'm still getting the same MBR errors.

Please post the diagnostics after running the command on a fresh boot.

tower-diagnostics-20221013-0039.zip

Post output of:

fdisk -l /dev/nvme0n1

 

I decided to take the drive out and make the MBR via disk management, and then put the drive back in the server, and I'm able to use it as a cache drive without issue now.

Same issue here. No matter how may times I delete partitions, clear disks or issue blkdiscard, the existing nfs partition on the first drive won't be replaced by the BTRFS one I create and in the second one, no partition is created altogether (same BTRFS).

 

On 10/13/2022 at 8:16 AM, JorgeB said:

Please post the diagnostics after running the command on a fresh boot.

 

I rebooted to run the diagnostics... and I could format the drives. 🤷‍♂️

Fresh boot sometimes helps, that's why I ask for that.

On 10/13/2022 at 11:32 AM, toasty_tt said:

I decided to take the drive out and make the MBR via disk management, and then put the drive back in the server, and I'm able to use it as a cache drive without issue now.

I am assuming that you rebooted the server during this operation?

Ie: shut down, remove disk, format in another machine, repace in original machine, startup?

 

Since this is marked as the solution, I wonder if its the reboot that is important?

Also, is there a way to reset this without rebooting?

Edited October 14, 20223 yr by KptnKMan