zfspools

ZFS Pools

Creating the ZFS Storage Pool

# zpool create tank c1t0d0
// -- Mirrored Storage Pool (mirror) --
# zpool create tank mirror c1t0d0 c1t1d0
// -- Single-Parity RAID-Z Storage Pool (raidz) --
# zpool create tank raidz c1t0d0 c2t0d0 c3t0d0 c4t0d0 /dev/dsk/c5t0d0
// -- Double-Parity RAID-Z Storage Pool (raidz2) --
# zpool create -f tank raidz2 c1t0d0 c2t0d0 c3t0d0

Change the default mount point

# zpool create -m /export/zfs home c1t0d0

Pools List

# zpool list
NAME SIZE USED AVAIL CAP HEALTH ALTROOT
tank  80G 137K   80G  0% ONLINE -

Status

# zpool status
// Listing Speciﬁc Storage Pool Statistics
# zpool list -o name,size
# zpool status -v tank
  pool: tank
 state: ONLINE
 scrub: none requested
config:

        NAME        STATE     READ WRITE CKSUM
        tank        ONLINE       0     0     0
          mirror    ONLINE       0     0     0
            c2t0d0  ONLINE       0     0     0
            c2t1d0  ONLINE       0     0     0

errors: No known data errors

Listing Pool-Wide Statistics

# zpool iostat
               capacity  operations  bandwidth
pool         used avail read write read write
---------- ----- ----- ----- ----- ----- -----
tank         100G 20.0G 1.2M 102K 1.2M 3.45K

Adding Devices to a Storage Pool

// dry run
# zpool add -n zeepool mirror c3t1d0 c3t2d0
// real add
# zpool add zeepool mirror c2t1d0 c2t2d0

Attaching and Detaching Devices in a Storage Pool

If the existing device is part of a two-way mirror, attaching the new device, creates a three-way mirror, and so on. In either case, the new device begins to resilver immediately.

# zpool attach zeepool c1t1d0 c2t1d0
# zpool detach zeepool c2t1d0

In this example, zeepool is an existing two-way mirror that is transformed to a three-way mirror by attaching c2t1d0, the new device, to the existing device, c1t1d0.

Onlining and Ofﬂining Devices in a Storage Pool

NOTE: Devices do not need to be taken ofﬂine in order to replace them.

You can use the offline command when you need to temporarily disconnect storage.

# zpool offline tank c1t0d0
bringing device c1t0d0 offline
# zpool online tank c1t0d0
bringing device c1t0d0 online

When a device is brought online, any data that has been written to the pool is resynchronized to the newly available device. Note that you cannot use device onlining to replace a disk. If you ofﬂine a device, replace the drive, and try to bring it online, it remains in the faulted state.

Replacing Devices in a Storage Pool

# zpool replace tank c1t1d0 c1t2d0

Designating Hot Spares

The hot spares feature enables you to identify disks that could be used to replace a failed or faulted device in one or more storage pools. Designating a device as a hot spare means that the device is not an active device in a pool, but if an active device in the pool fails, the hot spare automatically replaces the failed device.

// during creation
# zpool create zeepool mirror c1t1d0 c2t1d0 spare c1t2d0 c2t2d0
// or add them to the pool
# zpool add -f zeepool spare c1t3d0 c2t3d0

Destroying ZFS Storage Pools

# zpool destroy tank

Destroying a Pool With Faulted Devices

# zpool destroy tank
cannot destroy ’tank’: pool is faulted
use ’-f’ to force destruction anyway
# zpool destroy -f tank