Create pool

Created Sonntag 27 Oktober 2024

A pool is created with the first VDEV.
While creating a pool a root dataset is created with the same name as the pool and automatically mounted. Default mount point is /<Pool name>.
Root dataset name CAN NOT be changed.

Simple

Create a pool with one disk.
# zpool create <Pool name> <Device>

Examlpe

# zpool create mypool /dev/sda
# zpool create mypool sda

Multiple (RAID 0)

Create a pool with multiple disk. By default this creates a striped VDEV (RAID 0).
# zpool create <Pool name> <Device 1> <Device 2> ...

Examlpe

# zpool create mypool /dev/sda /dev/sdb
# zpool create mypool sda sdb

Mirror (RAID 1)

Create a pool with a mirrored VDEV. A mirror can include more than 2 devices.
# zpool create <Pool name> mirror <Device 1> <Device 2>

Examlpe

# zpool create mypool mirror sda sdb

Mirror (RAID 1) with more than 2 disks

Creating a mirror with more than 2 disks is possibe in that you create an additional mirror (with one disk).
# zpool create <Pool name> mirror <Device 1> <Device 2> mirror <Device 3>

Repeat the step for more disks.
zpool status will show a mirror VDEV per additional disk.

Examlpe

# zpool add mypool mirror sda sdb mirror sdc
In this case zool status will show two mirror VDEVs.
pool: mypool
state: ONLINE
scan: none requested
config:

errors: No known data errors

Mirror (RAID 1) Expand to more disks

Creating a mirror with more than 2 disks is possibe in that you create an additional mirror (with one disk).
# zpool add <Pool name> mirror <Device 3>

Repeat the step for more disks.
zpool status will show a mirror VDEV per additional disk.

Examlpe

# zpool add mypool mirror sdc
In this case zool status will show two mirror VDEVs.
pool: mypool
state: ONLINE
scan: none requested
config:

errors: No known data errors

RAIDZ[1] (RAID 5)

Create a pool with a VDEV group with 1 parity disk striped over at least 3 disks.
# zpool create <Pool name> raidz <Device 1> <Device 2> <Device 3>

Examlpe

# zpool create mypool raidz sdb sdc sdd

RAIDZ2 (RAID 6)

Create a pool with a VDEV group with 2 parity disk striped over at least 4 disks.
# zpool create <Pool name> raidz2 <Device 1> <Device 2> <Device 3> <Device 4>

RAIDZ3

Create a pool with a VDEV group with 3 parity disk striped over at least 5 disks.
# zpool create <Pool name> raidz3 <Device 1> <Device 2> <Device 3> <Device 4> <Device 5>

RAID 10

Creating something like a RAID 10 is possible with adding two mirrored VDEVs together.
# zpool create <Pool name> mirror <Device 1> <Device 2> mirror <Device 3> <Device 4>

Examlpe

# zpool create mypool mirror sdb sdc mirror sdd sde

Additional configuration

Pool root dataset mountpoint

Set the pool mountpoint while creating the pool. Without it will be /<Pool name> (on Ubuntu).
# zpool create <Pool name> -m <Mount path> mirror <Device 1> <Device 2> ...

ZFS is mounted automatically without a fstab entry.

Examlpe

# zpool create mypool -m /mnt/mypool mirror sdb sdc

Pool mountpoint

Create a pool with one disk mounted to /<Pool mountpoint>.
# zpool create -R /<Pool mountpoint> <Pool name> <Device>

Examlpe

Create a pool with one disk and a root dataset mypool2 mounted to /myroot/mypool2.
# zpool create -R /myroot create mypool2 sdb