Provided by: zfsutils-linux_2.1.9-2ubuntu1_amd64 
NAME
zpool — configure ZFS storage pools
SYNOPSIS
zpool -?V
zpool version
zpool subcommand [argumentss]
DESCRIPTION
The 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(8) for information on managing datasets.
For an overview of creating and managing ZFS storage pools see the zpoolconcepts(7) manual
page.
SUBCOMMANDS
All 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:
zpool -?
Displays a help message.
zpool -V, --version
zpool version
Displays the software version of the zpool userland utility and the ZFS kernel
module.
Creation
zpool-create(8)
Creates a new storage pool containing the virtual devices specified on the command
line.
zpool-initialize(8)
Begins initializing by writing to all unallocated regions on the specified devices,
or all eligible devices in the pool if no individual devices are specified.
Destruction
zpool-destroy(8)
Destroys the given pool, freeing up any devices for other use.
zpool-labelclear(8)
Removes ZFS label information from the specified device.
Virtual Devices
zpool-attach(8)/zpool-detach(8)
Increases or decreases redundancy by attaching or detaching a device on an existing
vdev (virtual device).
zpool-add(8)/zpool-remove(8)
Adds the specified virtual devices to the given pool, or removes the specified
device from the pool.
zpool-replace(8)
Replaces an existing device (which may be faulted) with a new one.
zpool-split(8)
Creates a new pool by splitting all mirrors in an existing pool (which decreases its
redundancy).
Properties
Available pool properties listed in the zpoolprops(7) manual page.
zpool-list(8)
Lists the given pools along with a health status and space usage.
zpool-get(8)/zpool-set(8)
Retrieves the given list of properties (or all properties if all is used) for the
specified storage pool(s).
Monitoring
zpool-status(8)
Displays the detailed health status for the given pools.
zpool-iostat(8)
Displays logical I/O statistics for the given pools/vdevs. Physical I/Os may be
observed via iostat(1).
zpool-events(8)
Lists all recent events generated by the ZFS kernel modules. These events are
consumed by the zed(8) and used to automate administrative tasks such as replacing a
failed device with a hot spare. That manual page also describes the subclasses and
event payloads that can be generated.
zpool-history(8)
Displays the command history of the specified pool(s) or all pools if no pool is
specified.
Maintenance
zpool-scrub(8)
Begins a scrub or resumes a paused scrub.
zpool-checkpoint(8)
Checkpoints the current state of pool, which can be later restored by zpool import
--rewind-to-checkpoint.
zpool-trim(8)
Initiates an immediate on-demand TRIM operation for all of the free space in a pool.
This operation informs the underlying storage devices of all blocks in the pool
which are no longer allocated and allows thinly provisioned devices to reclaim the
space.
zpool-sync(8)
This command forces all in-core dirty data to be written to the primary pool storage
and not the ZIL. It will also update administrative information including quota
reporting. Without arguments, zpool sync will sync all pools on the system.
Otherwise, it will sync only the specified pool(s).
zpool-upgrade(8)
Manage the on-disk format version of storage pools.
zpool-wait(8)
Waits until all background activity of the given types has ceased in the given pool.
Fault Resolution
zpool-offline(8)/zpool-online(8)
Takes the specified physical device offline or brings it online.
zpool-resilver(8)
Starts a resilver. If an existing resilver is already running it will be restarted
from the beginning.
zpool-reopen(8)
Reopen all the vdevs associated with the pool.
zpool-clear(8)
Clears device errors in a pool.
Import & Export
zpool-import(8)
Make disks containing ZFS storage pools available for use on the system.
zpool-export(8)
Exports the given pools from the system.
zpool-reguid(8)
Generates a new unique identifier for the pool.
EXIT STATUS
The following exit values are returned:
0 Successful completion.
1 An error occurred.
2 Invalid command line options were specified.
EXAMPLES
Example 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 sda sdb sdc sdd sde sdf
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 sda sdb mirror sdc sdd
Example 3: Creating a ZFS Storage Pool by Using Partitions
The following command creates an unmirrored pool using two disk partitions:
# zpool create tank sda1 sdb2
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 sda sdb
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 ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT
rpool 19.9G 8.43G 11.4G - 33% 42% 1.00x ONLINE -
tank 61.5G 20.0G 41.5G - 48% 32% 1.00x ONLINE -
zion - - - - - - - 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
pool: tank
id: 15451357997522795478
state: ONLINE
action: The pool can be imported using its name or numeric identifier.
config:
tank ONLINE
mirror ONLINE
sda ONLINE
sdb ONLINE
# 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 sda sdb spare sdc
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 sda sdd
Once the data has been resilvered, the spare is automatically removed and is made
available for use should another device fail. The hot spare can be permanently
removed from the pool using the following command:
# zpool remove tank sdc
Example 12: Creating a ZFS Pool with Mirrored Separate Intent Logs
The following command creates a ZFS storage pool consisting of two, two-way mirrors
and mirrored log devices:
# zpool create pool mirror sda sdb mirror sdc sdd log mirror sde sdf
Example 13: Adding Cache Devices to a ZFS Pool
The following command adds two disks for use as cache devices to a ZFS storage pool:
# zpool add pool cache sdc sdd
Once added, the cache devices gradually fill with content from main memory. Depending
on the size of your cache devices, it could take over an hour for them to fill.
Capacity and reads can be monitored using the iostat subcommand as follows:
# zpool iostat -v pool 5
Example 14: Removing a Mirrored top-level (Log or Data) Device
The following commands remove the mirrored log device mirror-2 and mirrored top-level
data device mirror-1.
Given this configuration:
pool: tank
state: ONLINE
scrub: none requested
config:
NAME STATE READ WRITE CKSUM
tank ONLINE 0 0 0
mirror-0 ONLINE 0 0 0
sda ONLINE 0 0 0
sdb ONLINE 0 0 0
mirror-1 ONLINE 0 0 0
sdc ONLINE 0 0 0
sdd ONLINE 0 0 0
logs
mirror-2 ONLINE 0 0 0
sde ONLINE 0 0 0
sdf ONLINE 0 0 0
The command to remove the mirrored log mirror-2 is:
# zpool remove tank mirror-2
The command to remove the mirrored data mirror-1 is:
# zpool remove tank mirror-1
Example 15: Displaying expanded space on a device
The following command displays the detailed information for the pool data. This pool
is comprised of a single raidz vdev where one of its devices increased its capacity by
10GB. In this example, the pool will not be able to utilize this extra capacity until
all the devices under the raidz vdev have been expanded.
# zpool list -v data
NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT
data 23.9G 14.6G 9.30G - 48% 61% 1.00x ONLINE -
raidz1 23.9G 14.6G 9.30G - 48%
sda - - - - -
sdb - - - 10G -
sdc - - - - -
Example 16: Adding output columns
Additional columns can be added to the zpool status and zpool iostat output with -c.
# zpool status -c vendor,model,size
NAME STATE READ WRITE CKSUM vendor model size
tank ONLINE 0 0 0
mirror-0 ONLINE 0 0 0
U1 ONLINE 0 0 0 SEAGATE ST8000NM0075 7.3T
U10 ONLINE 0 0 0 SEAGATE ST8000NM0075 7.3T
U11 ONLINE 0 0 0 SEAGATE ST8000NM0075 7.3T
U12 ONLINE 0 0 0 SEAGATE ST8000NM0075 7.3T
U13 ONLINE 0 0 0 SEAGATE ST8000NM0075 7.3T
U14 ONLINE 0 0 0 SEAGATE ST8000NM0075 7.3T
# zpool iostat -vc size
capacity operations bandwidth
pool alloc free read write read write size
---------- ----- ----- ----- ----- ----- ----- ----
rpool 14.6G 54.9G 4 55 250K 2.69M
sda1 14.6G 54.9G 4 55 250K 2.69M 70G
---------- ----- ----- ----- ----- ----- ----- ----
ENVIRONMENT VARIABLES
ZFS_ABORT Cause zpool to dump core on exit for the purposes of running
::findleaks.
ZFS_COLOR Use ANSI color in zpool status output.
ZPOOL_IMPORT_PATH The search path for devices or files to use with the pool.
This is a colon-separated list of directories in which zpool
looks for device nodes and files. Similar to the -d option in
zpool import.
ZPOOL_IMPORT_UDEV_TIMEOUT_MS The maximum time in milliseconds that zpool import will wait
for an expected device to be available.
ZPOOL_STATUS_NON_NATIVE_ASHIFT_IGNORE
If set, suppress warning about non-native vdev ashift in zpool
status. The value is not used, only the presence or absence
of the variable matters.
ZPOOL_VDEV_NAME_GUID Cause zpool subcommands to output vdev guids by default. This
behavior is identical to the zpool status -g command line
option.
ZPOOL_VDEV_NAME_FOLLOW_LINKS Cause zpool subcommands to follow links for vdev names by
default. This behavior is identical to the zpool status -L
command line option.
ZPOOL_VDEV_NAME_PATH Cause zpool subcommands to output full vdev path names by
default. This behavior is identical to the zpool status -P
command line option.
ZFS_VDEV_DEVID_OPT_OUT Older OpenZFS implementations had issues when attempting to
display pool config VDEV names if a devid NVP value is present
in the pool's config.
For example, a pool that originated on illumos platform would
have a devid value in the config and zpool status would fail
when listing the config. This would also be true for future
Linux-based pools.
A pool can be stripped of any devid values on import or
prevented from adding them on zpool create or zpool add by
setting ZFS_VDEV_DEVID_OPT_OUT.
ZPOOL_SCRIPTS_AS_ROOT Allow a privileged user to run zpool status/iostat -c.
Normally, only unprivileged users are allowed to run -c.
ZPOOL_SCRIPTS_PATH The search path for scripts when running zpool status/iostat
-c. This is a colon-separated list of directories and
overrides the default ~/.zpool.d and /etc/zfs/zpool.d search
paths.
ZPOOL_SCRIPTS_ENABLED Allow a user to run zpool status/iostat -c. If
ZPOOL_SCRIPTS_ENABLED is not set, it is assumed that the user
is allowed to run zpool status/iostat -c.
INTERFACE STABILITY
Evolving
SEE ALSO
zfs(4), zpool-features(7), zpoolconcepts(7), zpoolprops(7), zed(8), zfs(8), zpool-add(8),
zpool-attach(8), zpool-checkpoint(8), zpool-clear(8), zpool-create(8), zpool-destroy(8),
zpool-detach(8), zpool-events(8), zpool-export(8), zpool-get(8), zpool-history(8),
zpool-import(8), zpool-initialize(8), zpool-iostat(8), zpool-labelclear(8), zpool-list(8),
zpool-offline(8), zpool-online(8), zpool-reguid(8), zpool-remove(8), zpool-reopen(8),
zpool-replace(8), zpool-resilver(8), zpool-scrub(8), zpool-set(8), zpool-split(8),
zpool-status(8), zpool-sync(8), zpool-trim(8), zpool-upgrade(8), zpool-wait(8)