Hi there. I develop a disk management tool called "growlight", and have been tracking down a bug here: https://github.com/dankamongmen/growlight/issues/4 It came down to the fact that I've got two NVMe SSDs of the same model in this machine, both with a single namespace, both with a GPT partition table on said namespace, both with three partitions (laid out the same way), and libblkid thinks that the namespace device itself is TYPE="zfs_member". This does not happen for my spinning disks, and I believe it to be incorrect. Here's gdisk output for one of the SSDs: ------------------------------- [schwarzgerat](0) $ sudo gdisk /dev/nvme0n1 GPT fdisk (gdisk) version 1.0.3 Partition table scan: MBR: protective BSD: not present APM: not present GPT: present Found valid GPT with protective MBR; using GPT. Command (? for help): p Disk /dev/nvme0n1: 1953525168 sectors, 931.5 GiB Model: WDS100T3X0C-00SJG0 Sector size (logical/physical): 512/512 bytes Disk identifier (GUID): BF1C425C-02B7-4C9D-9E37-402BE6F84798 Partition table holds up to 128 entries Main partition table begins at sector 2 and ends at sector 33 First usable sector is 34, last usable sector is 1953525134 Partitions will be aligned on 2048-sector boundaries Total free space is 2014 sectors (1007.0 KiB) Number Start (sector) End (sector) Size Code Name 1 2048 2099199 1024.0 MiB EF00 EFI System 2 2099200 209717247 99.0 GiB FD00 Linux RAID 3 209717248 1953525134 831.5 GiB BF01 Solaris /usr & Mac ZFS ------------------------------- Everything looks good; there's a valid GPT, and it defines the three partitions we expect. The first partition is my ESP on /boot/efi, the second is half of a mdadm RAID1-backed ext4 on /, and the third is half of a ZFS mirror on /home. Here's blkid output for the namespace and the partition: ------------------------------- [schwarzgerat](0) $ sudo blkid -p -i /dev/nvme0n1p3 /dev/nvme0n1p3: VERSION="5000" LABEL="zhomez" UUID="7730803059136165722" UUID_SUB="1552588083735239772" TYPE="zfs_member" USAGE="filesystem" MINIMUM_IO_SIZE="512" PHYSICAL_SECTOR_SIZE="512" LOGICAL_SECTOR_SIZE="512" PART_ENTRY_SCHEME="gpt" PART_ENTRY_NAME="Solaris /usr & Mac ZFS" PART_ENTRY_UUID="e234214d-7642-4302-a041-c0b6b340ad58" PART_ENTRY_TYPE="6a898cc3-1dd2-11b2-99a6-080020736631" PART_ENTRY_NUMBER="3" PART_ENTRY_OFFSET="209717248" PART_ENTRY_SIZE="1743807887" PART_ENTRY_DISK="259:4" [schwarzgerat](0) $ sudo blkid -p -i /dev/nvme0n1 /dev/nvme0n1: VERSION="5000" LABEL="zhomez" UUID="7730803059136165722" UUID_SUB="1552588083735239772" TYPE="zfs_member" USAGE="filesystem" MINIMUM_IO_SIZE="512" PHYSICAL_SECTOR_SIZE="512" LOGICAL_SECTOR_SIZE="512" PTUUID="bf1c425c-02b7-4c9d-9e37-402be6f84798" PTTYPE="gpt" [schwarzgerat](0) $ ------------------------------- In contrast, here's a spinning disk plus its ZFS partition: ------------------------------- [schwarzgerat](0) $ sudo blkid -p -i /dev/sdf /dev/sdf: MINIMUM_IO_SIZE="4096" PHYSICAL_SECTOR_SIZE="4096" LOGICAL_SECTOR_SIZE="512" PTUUID="5df293fc-a619-104c-b8ba-02d4cd945ebe" PTTYPE="gpt" [schwarzgerat](0) $ sudo blkid -p -i /dev/sdf1 /dev/sdf1: VERSION="5000" LABEL="chungus" UUID="7155547617804506101" UUID_SUB="4552286815811062243" TYPE="zfs_member" USAGE="filesystem" MINIMUM_IO_SIZE="4096" PHYSICAL_SECTOR_SIZE="4096" LOGICAL_SECTOR_SIZE="512" PART_ENTRY_SCHEME="gpt" PART_ENTRY_NAME="zfs-cc3eec2efa0e4f94" PART_ENTRY_UUID="a36a2260-2980-174e-a33f-4232dca79d34" PART_ENTRY_TYPE="6a898cc3-1dd2-11b2-99a6-080020736631" PART_ENTRY_NUMBER="1" PART_ENTRY_OFFSET="2048" PART_ENTRY_SIZE="23437750272" PART_ENTRY_DISK="8:80" [schwarzgerat](0) $ ------------------------------- Note the absence of TYPE or USAGE or LABEL in sdf, in contrast to nvme0n1, where all are defined (equivalently to nvme0n1p3). The UUID is equal for nvme0n1 and nvme0n1p3, also. I can't imagine any interpretation where this is valid, though I'm sure one might exist. I'm looking at probe_zfs() now, but wanted to get this out there in case I'm just misunderstanding something. --rigorously, nick -- nick black -=- https://www.nick-black.com to make an apple pie from scratch, you need first invent a universe.
