ubuntu@maas:~$ apt policy curtin curtin: Installed: 18.1-17-gae48e86f-0ubuntu1~16.04.1 Candidate: 18.1-17-gae48e86f-0ubuntu1~16.04.1 Version table: *** 18.1-17-gae48e86f-0ubuntu1~16.04.1 500 500 http://archive.ubuntu.com/ubuntu xenial-proposed/universe amd64 Packages 100 /var/lib/dpkg/status ubuntu@maas-xenial5:~$ uname -a Linux maas-xenial5 4.4.0-127-generic #153-Ubuntu SMP Sat May 19 10:58:46 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux root@maas-xenial5:~# head -n1 curtin-install.log curtin: Installation started. (18.1-17-gae48e86f-0ubuntu1~16.04.1) root@maas-xenial5:~# grep -iPzo '(?s)storage.*?version' curtin-install-cfg.yaml storage: config: - grub_device: true id: sda model: QEMU HARDDISK name: sda ptable: msdos serial: drive-scsi0-0-0-0 type: disk wipe: superblock - id: sdd model: QEMU HARDDISK name: sdd serial: drive-scsi0-0-0-1 type: disk wipe: superblock - id: sdb model: QEMU HARDDISK name: sdb serial: drive-scsi0-0-0-3 type: disk wipe: superblock - id: sdc model: QEMU HARDDISK name: sdc serial: drive-scsi0-0-0-2 type: disk wipe: superblock - id: sde model: QEMU HARDDISK name: sde serial: drive-scsi1-0-0-0 type: disk wipe: superblock - id: sdf model: QEMU HARDDISK name: sdf serial: drive-scsi1-0-0-1 type: disk wipe: superblock - backing_device: sdc cache_device: sdb cache_mode: writeback id: bcache0 name: bcache0 type: bcache - backing_device: sdd cache_device: sdb cache_mode: writeback id: bcache1 name: bcache1 type: bcache - backing_device: sde cache_device: sdb cache_mode: writeback id: bcache2 name: bcache2 type: bcache - backing_device: sdf cache_device: sdb cache_mode: writeback id: bcache3 name: bcache3 type: bcache - device: sda id: sda-part1 name: sda-part1 number: 1 offset: 4194304B size: 68711088128B type: partition uuid: 11be5226-2264-4a1d-ba73-f2de4c6b7383 wipe: superblock - fstype: ext4 id: sda-part1_format label: root type: format uuid: a438e184-5dcf-4ae8-87c8-de5cda57704c volume: sda-part1 - device: sda-part1_format id: sda-part1_mount path: / type: mount version ubuntu@maas-xenial5:~$ sudo bcache-super-show /dev/sdc | grep -P 'dev.uuid|label' dev.label bcache0 dev.uuid 6e6a0acd-3791-4a56-8e97-1d5ab6687a5e ubuntu@maas-xenial5:~$ sudo bcache-super-show /dev/sdd | grep -P 'dev.uuid|label' dev.label bcache1 dev.uuid 5b453064-bdd4-41e6-b7c8-86fdaee0091a ubuntu@maas-xenial5:~$ sudo bcache-super-show /dev/sde | grep -P 'dev.uuid|label' dev.label bcache2 dev.uuid 71d73c42-6a82-47a7-a53d-a24929998c24 ubuntu@maas-xenial5:~$ sudo bcache-super-show /dev/sdf | grep -P 'dev.uuid|label' dev.label bcache3 dev.uuid 9732cbbd-3905-43a3-8e05-abaa7b09f791 ubuntu@maas-xenial5:~$ tree /dev/bcache /dev/bcache ├── by-label │   ├── bcache0 -> ../../bcache3 │   ├── bcache1 -> ../../bcache1 │   ├── bcache2 -> ../../bcache0 │   └── bcache3 -> ../../bcache2 └── by-uuid ├── 5b453064-bdd4-41e6-b7c8-86fdaee0091a -> ../../bcache1 ├── 6e6a0acd-3791-4a56-8e97-1d5ab6687a5e -> ../../bcache3 ├── 71d73c42-6a82-47a7-a53d-a24929998c24 -> ../../bcache0 └── 9732cbbd-3905-43a3-8e05-abaa7b09f791 -> ../../bcache2 2 directories, 8 files ubuntu@maas-xenial5:~$ tree /dev/disk/by-dname/ /dev/disk/by-dname/ ├── bcache0 -> ../../bcache3 ├── bcache1 -> ../../bcache1 ├── bcache2 -> ../../bcache0 ├── bcache3 -> ../../bcache2 ├── sda -> ../../sda └── sda-part1 -> ../../sda1 0 directories, 6 files ubuntu@maas-xenial5:~$ ls /sys/class/block/bcache*/slaves/ /sys/class/block/bcache0/slaves/: sdb sde /sys/class/block/bcache1/slaves/: sdb sdd /sys/class/block/bcache2/slaves/: sdb sdf /sys/class/block/bcache3/slaves/: sdb sdc # backing device config in MAAS maas maas machine read rynftc # ... { "used_for": "Backing device for bcache0", "type": "physical", "uuid": null, "filesystem": { "fstype": "bcache-backing", "label": null, "uuid": "590c8212-ad34-41ec-b1f3-1c9cfcc8a0b6", "mount_point": null, "mount_options": null }, "path": "/dev/disk/by-dname/sdc", "system_id": "rynftc", "used_size": 68719476736, "id_path": "/dev/disk/by-id/scsi-0QEMU_QEMU_HARDDISK_drive-scsi0-0-0-2", "serial": "drive-scsi0-0-0-2", "resource_uri": "/MAAS/api/2.0/nodes/rynftc/blockdevices/19/", "partition_table_type": null, "available_size": 0, "id": 19, "block_size": 4096, "partitions": [], "model": "QEMU HARDDISK", "size": 68719476736, "tags": [ "rotary", "data" ], "name": "sdc" }, { "used_for": "Backing device for bcache1", "type": "physical", "uuid": null, "filesystem": { "fstype": "bcache-backing", "label": null, "uuid": "5cc5fe63-24f6-4b62-8f0c-105425b16bc5", "mount_point": null, "mount_options": null }, "path": "/dev/disk/by-dname/sdd", "system_id": "rynftc", "used_size": 68719476736, "id_path": "/dev/disk/by-id/scsi-0QEMU_QEMU_HARDDISK_drive-scsi0-0-0-1", "serial": "drive-scsi0-0-0-1", "resource_uri": "/MAAS/api/2.0/nodes/rynftc/blockdevices/15/", "partition_table_type": null, "available_size": 0, "id": 15, "block_size": 4096, "partitions": [], "model": "QEMU HARDDISK", "size": 68719476736, "tags": [ "rotary", "data" ], "name": "sdd" }, { "used_for": "Backing device for bcache2", "type": "physical", "uuid": null, "filesystem": { "fstype": "bcache-backing", "label": null, "uuid": "92ff717d-cd61-4e6e-9c30-69113bdba19c", "mount_point": null, "mount_options": null }, "path": "/dev/disk/by-dname/sde", "system_id": "rynftc", "used_size": 68719476736, "id_path": "/dev/disk/by-id/scsi-0QEMU_QEMU_HARDDISK_drive-scsi1-0-0-0", "partition_table_type": null, "resource_uri": "/MAAS/api/2.0/nodes/rynftc/blockdevices/48/", "serial": "drive-scsi1-0-0-0", "available_size": 0, "id": 48, "block_size": 4096, "partitions": [], "model": "QEMU HARDDISK", "size": 68719476736, "tags": [ "rotary", "sst" ], "name": "sde" }, { "used_for": "Backing device for bcache3", "type": "physical", "uuid": null, "filesystem": { "fstype": "bcache-backing", "label": null, "uuid": "3670e128-36e9-454c-90fd-ebeb53c0571d", "mount_point": null, "mount_options": null }, "path": "/dev/disk/by-dname/sdf", "system_id": "rynftc", "used_size": 68719476736, "id_path": "/dev/disk/by-id/scsi-0QEMU_QEMU_HARDDISK_drive-scsi1-0-0-1", "partition_table_type": null, "resource_uri": "/MAAS/api/2.0/nodes/rynftc/blockdevices/49/", "serial": "drive-scsi1-0-0-1", "available_size": 0, "id": 49, "block_size": 4096, "partitions": [], "model": "QEMU HARDDISK", "size": 68719476736, "tags": [ "rotary", "wal" ], "name": "sdf" }