Manual browser: zpool(8)
|System Administration Commands
NAMEzpool - configures ZFS storage pools
zpool create [-fn] [-R root] [-m mountpoint] pool vdev ...
zpool destroy [-f] pool
zpool add [-fn] pool vdev
zpool remove pool vdev
zpool list [-H] [-o field[,field]*] [pool] ...
zpool iostat [-v] [pool] ... [interval [count]]
zpool status [-xv] [pool] ...
zpool offline [-t] pool device ...
zpool online pool device ...
zpool clear pool [device] ...
zpool attach [-f] pool device new_device
zpool detach pool device
zpool replace [-f] pool device [new_device]
zpool scrub [-s] pool ...
zpool export [-f] pool
zpool import [-d dir] [-D]
zpool import [-d dir] [-D] [-f] [-o opts] [-R root] pool | id
zpool import [-d dir] [-D] [-f] [-a]
zpool upgrade -v
zpool upgrade [-a | pool]
zpool history [pool] ...
DESCRIPTIONThe zpool command configures ZFS storage pools. A storage pool is a collection of devices that provides physical storage and data replication for ZFS datasets.
All datasets within a storage pool share the same space. See zfs(1M) for information on managing datasets.
Virtual Devices (vdevs)A "virtual device" describes a single device or a collection of devices organized according to certain performance and fault characteristics. The following virtual devices are supported:
Virtual devices cannot be nested, so a mirror or raidz virtual device can only contain files or disks. Mirrors of mirrors (or other combinations) are not allowed.
A pool can have any number of virtual devices at the top of the configuration (known as "root vdevs"). Data is dynamically distributed across all top-level devices to balance data among devices. As new virtual devices are added, ZFS automatically places data on the newly available devices.
Virtual devices are specified one at a time on the command line, separated by whitespace. The keywords "mirror" and "raidz" are used to distinguish where a group ends and another begins. For example, the following creates two root vdevs, each a mirror of two disks:
# zpool create mypool mirror c0t0d0 c0t1d0 mirror c1t0d0 c1t1d0
Device Failure and RecoveryZFS supports a rich set of mechanisms for handling device failure and data corruption. All metadata and data is checksummed, and ZFS automatically repairs bad data from a good copy when corruption is detected.
In order to take advantage of these features, a pool must make use of some form of redundancy, using either mirrored or raidz groups. While ZFS supports running in a non-redundant configuration, where each root vdev is simply a disk or file, this is strongly discouraged. A single case of bit corruption can render some or all of your data unavailable.
A pool's health status is described by one of three states: online, degraded, or faulted. An online pool has all devices operating normally. A degraded pool is one in which one or more devices have failed, but the data is still available due to a redundant configuration. A faulted pool has one or more failed devices, and there is insufficient redundancy to replicate the missing data.
Hot SparesZFS allows devices to be associated with pools as "hot spares". These devices are not actively used in the pool, but when an active device fails, it is automatically replaced by a hot spare. To create a pool with hot spares, specify a "spare" vdev with any number of devices. For example,
# zpool create pool mirror c0d0 c1d0 spare c2d0 c3d0
Spares can be shared across multiple pools, and can be added with the "zpool add" command and removed with the "zpool remove" command. Once a spare replacement is initiated, a new "spare" vdev is created within the configuration that will remain there until the original device is replaced. At this point, the hot spare becomes available again if another device fails.
An in-progress spare replacement can be cancelled by detaching the hot spare. If the original faulted device is detached, then the hot spare assumes its place in the configuration, and is removed from the spare list of all active pools.
Alternate Root PoolsThe "zpool create -R" and "zpool import -R" commands allow users to create and import a pool with a different root path. By default, whenever a pool is created or imported on a system, it is permanently added so that it is available whenever the system boots. For removable media, or when in recovery situations, this may not always be desirable. An alternate root pool does not persist on the system. Instead, it exists only until exported or the system is rebooted, at which point it will have to be imported again.
In addition, all mount points in the pool are prefixed with the given root, so a pool can be constrained to a particular area of the file system. This is most useful when importing unknown pools from removable media, as the mount points of any file systems cannot be trusted.
When creating an alternate root pool, the default mount point is "/", rather than the normal default "/pool".
SubcommandsAll subcommands that modify state are logged persistently to the pool in their original form.
The zpool command provides subcommands to create and destroy storage pools, add capacity to storage pools, and provide information about the storage pools. The following subcommands are supported:
name Pool name
size Total size
used Amount of space used
available Amount of space available
capacity Percentage of pool space used
health Health status
EXAMPLESExample 1 Creating a RAID-Z Storage Pool
The following command creates a pool with a single raidz root vdev that consists of six disks.
# zpool create tank raidz c0t0d0 c0t1d0 c0t2d0 c0t3d0 c0t4d0 c0t5d0
Example 2 Creating a Mirrored Storage Pool
The following command creates a pool with two mirrors, where each mirror contains two disks.
# zpool create tank mirror c0t0d0 c0t1d0 mirror c0t2d0 c0t3d0
Example 3 Creating a ZFS Storage Pool by Using Slices
The following command creates an unmirrored pool using two disk slices.
# zpool create tank /dev/dsk/c0t0d0s1 c0t1d0s4
Example 4 Creating a ZFS Storage Pool by Using Files
The following command creates an unmirrored pool using files. While not recommended, a pool based on files can be useful for experimental purposes.
# zpool create tank /path/to/file/a /path/to/file/b
Example 5 Adding a Mirror to a ZFS Storage Pool
The following command adds two mirrored disks to the pool "tank", assuming the pool is already made up of two-way mirrors. The additional space is immediately available to any datasets within the pool.
# zpool add tank mirror c1t0d0 c1t1d0
Example 6 Listing Available ZFS Storage Pools
The following command lists all available pools on the system. In this case, the pool zion is faulted due to a missing device.
The results from this command are similar to the following:
# zpool list
NAME SIZE USED AVAIL CAP HEALTH ALTROOT
pool 67.5G 2.92M 67.5G 0% ONLINE -
tank 67.5G 2.92M 67.5G 0% ONLINE -
zion - - - 0% FAULTED -
Example 7 Destroying a ZFS Storage Pool
The following command destroys the pool "tank" and any datasets contained within.
# zpool destroy -f tank
Example 8 Exporting a ZFS Storage Pool
The following command exports the devices in pool tank so that they can be relocated or later imported.
# zpool export tank
Example 9 Importing a ZFS Storage Pool
The following command displays available pools, and then imports the pool "tank" for use on the system.
The results from this command are similar to the following:
# zpool import
action: The pool can be imported using its name or numeric identifier.
# zpool import tank
Example 10 Upgrading All ZFS Storage Pools to the Current Version
The following command upgrades all ZFS Storage pools to the current version of the software.
# zpool upgrade -a
This system is currently running ZFS version 2.
Example 11 Managing Hot Spares
The following command creates a new pool with an available hot spare:
# zpool create tank mirror c0t0d0 c0t1d0 spare c0t2d0
If one of the disks were to fail, the pool would be reduced to the degraded state. The failed device can be replaced using the following command:
# zpool replace tank c0t0d0 c0t3d0
Once the data has been resilvered, the spare is automatically removed and is made available should another device fails. The hot spare can be permanently removed from the pool using the following command:
# zpool remove tank c0t2d0
EXIT STATUSThe following exit values are returned:
ATTRIBUTESSee attributes(5) for descriptions of the following attributes:
SEE ALSOzfs(1M), attributes(5)
|14 Nov 2006