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zpool(1M)		System Administration Commands		     zpool(1M)

NAME
       zpool - configures ZFS storage pools

SYNOPSIS
       zpool [-?]

       zpool add [-fn] pool vdev ...

       zpool attach [-f] pool device new_device

       zpool clear pool [device]

       zpool create [-fn] [-o property=value] ... [-O file-system-property=value]
	    ... [-m mountpoint] [-R root] pool vdev ...

       zpool destroy [-f] pool

       zpool detach pool device

       zpool export [-f] pool ...

       zpool get "all" | property[,...] pool ...

       zpool history [-il] [pool] ...

       zpool import [-d dir] [-D]

       zpool import [-o mntopts] [-o property=value] ... [-d dir | -c cachefile]
	    [-D] [-f] [-R root] -a

       zpool import [-o mntopts] [-o property=value] ... [-d dir | -c cachefile]
	    [-D] [-f] [-R root] pool |id [newpool]

       zpool iostat [-T u | d ] [-v] [pool] ... [interval[count]]

       zpool labelclear [-f] device

       zpool list [-H] [-o property[,...]] [pool] ...

       zpool offline [-t] pool device ...

       zpool online pool device ...

       zpool remove pool device ...

       zpool replace [-f] pool device [new_device]

       zpool scrub [-s] pool ...

       zpool set property=value pool

       zpool status [-xv] [pool] ...

       zpool upgrade

       zpool upgrade -v

       zpool upgrade [-V version] -a | pool ...

DESCRIPTION
       The  zpool  command  configures	ZFS storage pools. A storage pool is a
       collection of devices that provides physical storage and data  replica-
       tion 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:

       disk	 A block device, typically located under /dev/dsk. ZFS can use
		 individual  slices or partitions, though the recommended mode
		 of operation is to use whole disks. A disk can  be  specified
		 by  a	full path, or it can be a shorthand name (the relative
		 portion of the path under "/dev/dsk"). A whole  disk  can  be
		 specified by omitting the slice or partition designation. For
		 example, "c0t0d0" is equivalent to "/dev/dsk/c0t0d0s2".  When
		 given	a  whole  disk,  ZFS automatically labels the disk, if
		 necessary.

       file	 A regular file. The use  of  files  as  a  backing  store  is
		 strongly discouraged. It is designed primarily for experimen-
		 tal purposes, as the fault tolerance of a  file  is  only  as
		 good as the file system of which it is a part. A file must be
		 specified by a full path.

       mirror	 A mirror of two or more devices. Data	is  replicated	in  an
		 identical fashion across all components of a mirror. A mirror
		 with N disks of size X can hold X  bytes  and	can  withstand
		 (N-1) devices failing before data integrity is compromised.

       raidz	 A  variation on RAID-5 that allows for better distribution of
       raidz1	 parity and eliminates the "RAID-5 write hole" (in which  data
       raidz2	 and  parity become inconsistent after a power loss). Data and
       raidz3	 parity is striped across all disks within a raidz group.

		 A raidz group can have single-, double- , or  triple  parity,
		 meaning  that	the raidz group can sustain one, two, or three
		 failures, respectively, without losing any data.  The	raidz1
		 vdev  type  specifies a single-parity raidz group; the raidz2
		 vdev type specifies a	double-parity  raidz  group;  and  the
		 raidz3  vdev  type specifies a triple-parity raidz group. The
		 raidz vdev type is an alias for raidz1.

		 A raidz group with N disks of size X with P parity disks  can
		 hold	approximately	(N-P)*X  bytes	and  can  withstand  P
		 device(s) failing before data integrity is  compromised.  The
		 minimum  number  of devices in a raidz group is one more than
		 the number of parity disks. The recommended number is between
		 3 and 9 to help increase performance.

       spare	 A  special  pseudo-vdev  which  keeps	track of available hot
		 spares for a pool. For more information, see the "Hot Spares"
		 section.

       log	 A  separate-intent log device. If more than one log device is
		 specified, then writes are load-balanced between devices. Log
		 devices  can  be  mirrored. However, raidz vdev types are not
		 supported for the intent log. For more information,  see  the
		 "Intent Log" section.

       cache	 A device used to cache storage pool data. A cache device can-
		 not be cannot be configured as a mirror or raidz  group.  For
		 more information, see the "Cache Devices" section.

       Virtual	devices  cannot be nested, so a mirror or raidz virtual device
       can only contain files or disks. Mirrors of mirrors (or other  combina-
       tions) are not allowed.

       A pool can have any number of virtual devices at the top of the config-
       uration (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, sepa-
       rated by whitespace. The keywords "mirror" and "raidz" are used to dis-
       tinguish  where	a group ends and another begins. For example, the fol-
       lowing creates two root vdevs, each a mirror of two disks:

	 # zpool create mypool mirror c0t0d0 c0t1d0 mirror c1t0d0 c1t1d0

   Device Failure and Recovery
       ZFS supports a rich set of mechanisms for handling device  failure  and
       data corruption. All metadata and data is checksummed, and ZFS automat-
       ically 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  nor-
       mally. 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  corrupted metadata, or one or more faulted devices,
       and insufficient replicas to continue functioning.

       The health of the top-level vdev, such as mirror or  raidz  device,  is
       potentially impacted by the state of its associated vdevs, or component
       devices. A top-level vdev or component device is in one of the  follow-
       ing states:

       DEGRADED    One	or  more  top-level  vdevs  is	in  the degraded state
		   because one or more component devices are  offline.	Suffi-
		   cient replicas exist to continue functioning.

		   One or more component devices is in the degraded or faulted
		   state, but sufficient replicas exist to continue  function-
		   ing. The underlying conditions are as follows:

		       o      The number of checksum errors exceeds acceptable
			      levels and the device is degraded as an  indica-
			      tion  that something may be wrong. ZFS continues
			      to use the device as necessary.

		       o      The number of I/O errors exceeds acceptable lev-
			      els.  The  device could not be marked as faulted
			      because there are insufficient replicas to  con-
			      tinue functioning.

       FAULTED	   One or more top-level vdevs is in the faulted state because
		   one or more component  devices  are	offline.  Insufficient
		   replicas exist to continue functioning.

		   One	or more component devices is in the faulted state, and
		   insufficient replicas exist to  continue  functioning.  The
		   underlying conditions are as follows:

		       o      The device could be opened, but the contents did
			      not match expected values.

		       o      The number of I/O errors exceeds acceptable lev-
			      els and the device is faulted to prevent further
			      use of the device.

       OFFLINE	   The device was  explicitly  taken  offline  by  the	"zpool
		   offline" command.

       ONLINE	   The device is online and functioning.

       REMOVED	   The device was physically removed while the system was run-
		   ning. Device removal detection  is  hardware-dependent  and
		   may not be supported on all platforms.

       UNAVAIL	   The	device could not be opened. If a pool is imported when
		   a device was unavailable, then the device will  be  identi-
		   fied  by  a unique identifier instead of its path since the
		   path was never correct in the first place.

       If a device is  removed	and  later  re-attached  to  the  system,  ZFS
       attempts  to  put the device online automatically. Device attach detec-
       tion is hardware-dependent and might not be supported on all platforms.

   Hot Spares
       ZFS  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.

       If a pool has a shared spare that is currently being used, the pool can
       not  be exported since other pools may use this shared spare, which may
       lead to potential data corruption.

       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.

       Spares cannot replace log devices.

   Intent Log
       The  ZFS  Intent Log (ZIL) satisfies POSIX requirements for synchronous
       transactions. For instance, databases often require their  transactions
       to  be on stable storage devices when returning from a system call. NFS
       and other applications can also use fsync() to ensure  data  stability.
       By  default,  the  intent  log is allocated from blocks within the main
       pool. However, it might be possible to  get  better  performance  using
       separate  intent  log  devices  such  as NVRAM or a dedicated disk. For
       example:

	 # zpool create pool c0d0 c1d0 log c2d0

       Multiple log devices can also be specified, and they can  be  mirrored.
       See  the  EXAMPLES  section  for  an  example of mirroring multiple log
       devices.

       Log devices can be added, replaced, attached,  detached,  and  imported
       and  exported  as  part of the larger pool. Mirrored log devices can be
       removed by specifying the top-level mirror for the log.

   Cache Devices
       Devices can be added to	a  storage  pool  as  "cache  devices."  These
       devices	provide an additional layer of caching between main memory and
       disk. For read-heavy workloads, where the  working  set	size  is  much
       larger  than  what  can	be  cached in main memory, using cache devices
       allow much more of this working set  to	be  served  from  low  latency
       media.  Using  cache devices provides the greatest performance improve-
       ment for random read-workloads of mostly static content.

       To create a pool with cache devices, specify a "cache"  vdev  with  any
       number of devices. For example:

	 # zpool create pool c0d0 c1d0 cache c2d0 c3d0

       Cache devices cannot be mirrored or part of a raidz configuration. If a
       read error is encountered on a cache device, that read I/O is  reissued
       to  the original storage pool device, which might be part of a mirrored
       or raidz configuration.

       The content of the cache devices is considered volatile, as is the case
       with other system caches.

   Properties
       Each  pool  has	several properties associated with it. Some properties
       are read-only statistics while others are configurable and  change  the
       behavior of the pool. The following are read-only properties:

       available	   Amount  of  storage available within the pool. This
			   property can also be referred to by	its  shortened
			   column name, "avail".

       capacity 	   Percentage  of  pool  space used. This property can
			   also be referred to by its shortened  column  name,
			   "cap".

       health		   The	current  health  of  the  pool.  Health can be
			   "ONLINE",  "DEGRADED",   "FAULTED",	 "   OFFLINE",
			   "REMOVED", or "UNAVAIL".

       guid		   A unique identifier for the pool.

       size		   Total size of the storage pool.

       used		   Amount of storage space used within the pool.

       These  space usage properties report actual physical space available to
       the storage pool. The physical space can be different  from  the  total
       amount  of  space  that	any  contained	datasets can actually use. The
       amount of space used in a raidz configuration depends on the character-
       istics  of the data being written. In addition, ZFS reserves some space
       for internal accounting that the zfs(1M) command  takes	into  account,
       but  the  zpool	command  does  not. For non-full pools of a reasonable
       size, these effects should be invisible. For small pools, or pools that
       are close to being completely full, these discrepancies may become more
       noticeable.

       The following property can be set at creation time and import time:

       altroot

	   Alternate root directory. If set, this directory  is  prepended  to
	   any	mount  points within the pool. This can be used when examining
	   an unknown pool where the mount points cannot be trusted, or in  an
	   alternate  boot environment, where the typical paths are not valid.
	   altroot is not a persistent property. It is valid  only  while  the
	   system  is  up.  Setting  altroot defaults to using cachefile=none,
	   though this may be overridden     using an explicit setting.

       The following properties can be set at creation time and  import  time,
       and later changed with the zpool set command:

       autoexpand=on | off

	   Controls automatic pool expansion when the underlying LUN is grown.
	   If set to on, the pool will be resized according to the size of the
	   expanded  device.  If  the device is part of a mirror or raidz then
	   all devices within that mirror/raidz group must be expanded	before
	   the	new  space is made available to the pool. The default behavior
	   is off. This property can also be referred to by its shortened col-
	   umn name, expand.

       autoreplace=on | off

	   Controls  automatic	device	replacement.  If  set to "off", device
	   replacement must be initiated by the  administrator	by  using  the
	   "zpool  replace"  command. If set to "on", any new device, found in
	   the same physical location as a device that previously belonged  to
	   the	pool,  is  automatically  formatted  and replaced. The default
	   behavior is "off". This property can also be  referred  to  by  its
	   shortened column name, "replace".

       bootfs=pool/dataset

	   Identifies  the  default  bootable  dataset for the root pool. This
	   property is expected to be  set  mainly  by	the  installation  and
	   upgrade programs.

       cachefile=path | none

	   Controls  the  location  of where the pool configuration is cached.
	   Discovering all pools on system startup requires a cached  copy  of
	   the	configuration data that is stored on the root file system. All
	   pools in this cache are  automatically  imported  when  the	system
	   boots.  Some  environments, such as install and clustering, need to
	   cache this information in a different location so  that  pools  are
	   not	automatically  imported. Setting this property caches the pool
	   configuration in a different location that can  later  be  imported
	   with "zpool import -c". Setting it to the special value "none" cre-
	   ates a temporary pool that is never cached, and the	special  value
	   '' (empty string) uses the default location.

	   Multiple  pools  can  share the same cache file. Because the kernel
	   destroys and recreates this file when pools are added and  removed,
	   care  should be taken when attempting to access this file. When the
	   last pool using a cachefile is exported or destroyed, the  file  is
	   removed.

       delegation=on | off

	   Controls  whether  a non-privileged user is granted access based on
	   the dataset permissions defined on the  dataset.  See  zfs(1M)  for
	   more information on ZFS delegated administration.

       failmode=wait | continue | panic

	   Controls  the  system  behavior  in	the event of catastrophic pool
	   failure. This condition is typically a result of a loss of  connec-
	   tivity  to  the  underlying	storage  device(s) or a failure of all
	   devices within the pool. The behavior of such an  event  is	deter-
	   mined as follows:

	   wait        Blocks  all I/O access until the device connectivity is
		       recovered and the  errors  are  cleared.  This  is  the
		       default behavior.

	   continue    Returns	EIO  to  any new write I/O requests but allows
		       reads to any of	the  remaining	healthy  devices.  Any
		       write  requests	that  have yet to be committed to disk
		       would be blocked.

	   panic       Prints out a message to the  console  and  generates  a
		       system crash dump.

       listsnaps=on | off

	   Controls  whether  information about snapshots associated with this
	   pool is output when "zfs list" is run without the  -t  option.  The
	   default value is "off".

       version=version

	   The current on-disk version of the pool. This can be increased, but
	   never decreased. The preferred method of updating pools is with the
	   "zpool  upgrade"  command,  though this property can be used when a
	   specific version is needed for backwards compatibility. This  prop-
	   erty  can  be any number between 1 and the current version reported
	   by "zpool upgrade -v".

   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 add [-fn] pool vdev ...

	   Adds  the  specified  virtual  devices  to the given pool. The vdev
	   specification is described in the "Virtual  Devices"  section.  The
	   behavior  of  the  -f  option,  and the device checks performed are
	   described in the "zpool create" subcommand.

	   -f	 Forces use of vdevs, even if they appear in use or specify  a
		 conflicting  replication  level. Not all devices can be over-
		 ridden in this manner.

	   -n	 Displays the configuration that would be used	without  actu-
		 ally  adding  the  vdevs.  The actual pool creation can still
		 fail due to insufficient privileges or device sharing.

	   Do not add a disk that is currently configured as a	quorum	device
	   to a zpool. After a disk is in the pool, that disk can then be con-
	   figured as a quorum device.

       zpool attach [-f] pool device new_device

	   Attaches new_device to  an  existing  zpool	device.  The  existing
	   device  cannot  be  part of a raidz configuration. If device is not
	   currently part of a mirrored  configuration,  device  automatically
	   transforms  into  a	two-way  mirror  of  device and new_device. If
	   device is part of a two-way mirror, attaching new_device creates  a
	   three-way  mirror,  and so on. In either case, new_device begins to
	   resilver immediately.

	   -f	 Forces use of new_device, even if its appears to be  in  use.
		 Not all devices can be overridden in this manner.

       zpool clear pool [device] ...

	   Clears  device errors in a pool. If no arguments are specified, all
	   device errors within the pool are cleared. If one or  more  devices
	   is  specified,  only  those	errors	associated  with the specified
	   device or devices are cleared.

       zpool create [-fn] [-o property=value] ... [-O file-system-prop-
       erty=value] ... [-m mountpoint] [-R root] pool vdev ...

	   Creates a new storage pool containing the virtual devices specified
	   on the command line. The pool name must begin with  a  letter,  and
	   can	only  contain  alphanumeric  characters  as well as underscore
	   ("_"), dash ("-"), and  period  (".").  The	pool  names  "mirror",
	   "raidz",  "spare"  and  "log"  are reserved, as are names beginning
	   with the pattern "c[0-9]". The vdev specification is  described  in
	   the "Virtual Devices" section.

	   The	command  verifies that each device specified is accessible and
	   not currently in use by another subsystem.  There  are  some  uses,
	   such as being currently mounted, or specified as the dedicated dump
	   device, that prevents a device from ever being used by  ZFS.  Other
	   uses, such as having a preexisting UFS file system, can be overrid-
	   den with the -f option.

	   The command also checks that the replication strategy for the  pool
	   is  consistent.  An	attempt to combine redundant and non-redundant
	   storage in a single pool, or to mix disks and files, results in  an
	   error  unless -f is specified. The use of differently sized devices
	   within a single raidz or mirror group is also flagged as  an  error
	   unless -f is specified.

	   Unless  the	-R  option  is	specified,  the default mount point is
	   "/pool". The mount point must not exist or must be empty,  or  else
	   the root dataset cannot be mounted. This can be overridden with the
	   -m option.

	   -f

	       Forces use of vdevs, even if they appear in use	or  specify  a
	       conflicting  replication level. Not all devices can be overrid-
	       den in this manner.

	   -n

	       Displays the configuration that would be used without  actually
	       creating  the pool. The actual pool creation can still fail due
	       to insufficient privileges or device sharing.

	   -o property=value [-o property=value] ...

	       Sets the given pool properties. See  the  "Properties"  section
	       for a list of valid properties that can be set.

	   -O file-system-property=value
	   [-O file-system-property=value] ...

	       Sets  the  given file system properties in the root file system
	       of the pool. See the "Properties" section of zfs(1M) for a list
	       of valid properties that can be set.

	   -R root

	       Equivalent to "-o cachefile=none,altroot=root"

	   -m mountpoint

	       Sets  the  mount  point for the root dataset. The default mount
	       point is "/pool" or "altroot/pool" if altroot is specified. The
	       mount  point must be an absolute path, "legacy", or "none". For
	       more information on dataset mount points, see zfs(1M).

       zpool destroy [-f] pool

	   Destroys the given pool, freeing up any devices for other use. This
	   command  tries to unmount any active datasets before destroying the
	   pool.

	   -f	 Forces any active datasets contained within the  pool	to  be
		 unmounted.

       zpool detach pool device

	   Detaches  device  from  a mirror. The operation is refused if there
	   are no other valid replicas of the data.

       zpool export [-f] pool ...

	   Exports the given pools from the system. All devices are marked  as
	   exported,  but are still considered in use by other subsystems. The
	   devices can be moved between systems (even those of different endi-
	   anness)  and imported as long as a sufficient number of devices are
	   present.

	   Before exporting  the  pool,  all  datasets	within	the  pool  are
	   unmounted. A pool can not be exported if it has a shared spare that
	   is currently being used.

	   For pools to be portable, you must give  the  zpool	command  whole
	   disks, not just slices, so that ZFS can label the disks with porta-
	   ble EFI labels. Otherwise, disk drivers on platforms  of  different
	   endianness will not recognize the disks.

	   -f	 Forcefully  unmount all datasets, using the "unmount -f" com-
		 mand.

		 This command will forcefully export the pool even if it has a
		 shared  spare	that is currently being used. This may lead to
		 potential data corruption.

       zpool get "all" | property[,...] pool ...

	   Retrieves the given list of properties (or all properties if  "all"
	   is  used)  for  the specified storage pool(s). These properties are
	   displayed with the following fields:

		    name	  Name of storage pool
		     property	   Property name
		     value	   Property value
		     source	   Property source, either 'default' or 'local'.

	   See the "Properties" section for more information on the  available
	   pool properties.

       zpool history [-il] [pool] ...

	   Displays the command history of the specified pools or all pools if
	   no pool is specified.

	   -i	 Displays internally logged ZFS events	in  addition  to  user
		 initiated events.

	   -l	 Displays  log	records  in  long format, which in addition to
		 standard format includes, the user name,  the	hostname,  and
		 the zone in which the operation was performed.

       zpool import [-d dir | -c cachefile] [-D]

	   Lists pools available to import. If the -d option is not specified,
	   this command searches for devices in "/dev/dsk". The -d option  can
	   be  specified  multiple times, and all directories are searched. If
	   the device appears to be part of an	exported  pool,  this  command
	   displays a summary of the pool with the name of the pool, a numeric
	   identifier, as well as the vdev layout and current  health  of  the
	   device  for	each  device or file. Destroyed pools, pools that were
	   previously destroyed with the  "zpool  destroy"  command,  are  not
	   listed unless the -D option is specified.

	   The	numeric  identifier  is unique, and can be used instead of the
	   pool name when multiple exported pools of the same name are	avail-
	   able.

	   -c cachefile    Reads  configuration  from the given cachefile that
			   was created with  the  "cachefile"  pool  property.
			   This  cachefile  is	used  instead of searching for
			   devices.

	   -d dir	   Searches for devices or files in dir. The -d option
			   can be specified multiple times.

	   -D		   Lists destroyed pools only.

       zpool import [-o mntopts] [ -o property=value] ... [-d dir | -c
       cachefile] [-D] [-f] [-R root] -a

	   Imports all pools found in the search directories. Identical to the
	   previous command, except that all pools with a sufficient number of
	   devices available are imported. Destroyed pools,  pools  that  were
	   previously  destroyed with the "zpool destroy" command, will not be
	   imported unless the -D option is specified.

	   -o mntopts		Comma-separated list of mount options  to  use
				when  mounting	datasets  within the pool. See
				zfs(1M) for a description of  dataset  proper-
				ties and mount options.

	   -o property=value	Sets  the  specified  property on the imported
				pool. See the "Properties"  section  for  more
				information  on the available pool properties.

	   -c cachefile 	Reads configuration from the  given  cachefile
				that  was  created  with  the "cachefile" pool
				property. This cachefile is  used  instead  of
				searching for devices.

	   -d dir		Searches  for  devices or files in dir. The -d
				option can be specified multiple  times.  This
				option is incompatible with the -c option.

	   -D			Imports destroyed pools only. The -f option is
				also required.

	   -f			Forces import, even if the pool appears to  be
				potentially active.

	   -a			Searches for and imports all pools found.

	   -R root		Sets  the  "cachefile"	property to "none" and
				the "altroot" property to "root".

       zpool import [-o mntopts] [ -o property=value] ... [-d dir | -c
       cachefile] [-D] [-f] [-R root] pool | id [newpool]

	   Imports  a  specific  pool. A pool can be identified by its name or
	   the numeric identifier.  If	newpool  is  specified,  the  pool  is
	   imported using the name newpool. Otherwise, it is imported with the
	   same name as its exported name.

	   If a device is removed from a system without running "zpool export"
	   first,  the	device	appears  as  potentially  active. It cannot be
	   determined if this was a failed export, or whether  the  device  is
	   really  in  use  from another host. To import a pool in this state,
	   the -f option is required.

	   -o mntopts

	       Comma-separated list of mount  options  to  use	when  mounting
	       datasets  within  the  pool.  See  zfs(1M) for a description of
	       dataset properties and mount options.

	   -o property=value

	       Sets the specified property  on	the  imported  pool.  See  the
	       "Properties" section for more information on the available pool
	       properties.

	   -c cachefile

	       Reads configuration from the given cachefile that  was  created
	       with  the  "cachefile"  pool  property.	This cachefile is used
	       instead of searching for devices.

	   -d dir

	       Searches for devices or files in dir.  The  -d  option  can  be
	       specified  multiple times. This option is incompatible with the
	       -c option.

	   -D

	       Imports destroyed pool. The -f option is also required.

	   -f

	       Forces import, even if  the  pool  appears  to  be  potentially
	       active.

	   -R root

	       Sets the "cachefile" property to "none" and the "altroot" prop-
	       erty to "root".

       zpool iostat [-T u | d] [-v] [pool] ... [interval[count]]

	   Displays I/O statistics for the given pools. When given  an	inter-
	   val, the statistics are printed every interval seconds until Ctrl-C
	   is pressed. If no pools are specified, statistics for every pool in
	   the system is shown. If count is specified, the command exits after
	   count reports are printed.

	   -T u | d    Display a time stamp.

		       Specify u for a printed representation of the  internal
		       representation  of  time.  See  time(2).  Specify d for
		       standard date format. See date(1).

	   -v	       Verbose statistics. Reports usage statistics for  indi-
		       vidual  vdevs within the pool, in addition to the pool-
		       wide statistics.

       zpool labelclear [-f] device

	   Removes ZFS label information from the specified device. The device
	   must not be part of an active pool configuration.

	   -f	       Treat exported or foreign devices as inactive.

       zpool list [-H] [-o props[,...]] [pool] ...

	   Lists  the  given pools along with a health status and space usage.
	   When given no arguments, all pools in the system are listed.

	   -H	       Scripted mode. Do not  display  headers,  and  separate
		       fields by a single tab instead of arbitrary space.

	   -o props    Comma-separated	list of properties to display. See the
		       "Properties" section for a list	of  valid  properties.
		       The  default  list  is  "name,  size,  used, available,
		       capacity, health, altroot"

       zpool offline [-t] pool device ...

	   Takes the specified physical device offline. While  the  device  is
	   offline, no attempt is made to read or write to the device.

	   This command is not applicable to spares or cache devices.

	   -t	 Temporary. Upon reboot, the specified physical device reverts
		 to its previous state.

       zpool online [-e] pool device...

	   Brings the specified physical device online.

	   This command is not applicable to spares or cache devices.

	   -e	 Expand the device to use all available space. If  the	device
		 is  part  of  a  mirror  or  raidz  then  all devices must be
		 expanded before the new space will become  available  to  the
		 pool.

       zpool remove pool device ...

	   Removes  the specified device from the pool. This command currently
	   only supports removing hot spares, cache, and log devices.  A  mir-
	   rored  log device can be removed by specifying the top-level mirror
	   for the log. Non-log devices that are part of a mirrored configura-
	   tion  can  be removed using the zpool detach command. Non-redundant
	   and raidz devices cannot be removed from a pool.

       zpool replace [-f] pool old_device [new_device]

	   Replaces old_device with new_device. This is equivalent to  attach-
	   ing	new_device,  waiting  for  it  to resilver, and then detaching
	   old_device.

	   The size of new_device must be greater than or equal to the minimum
	   size of all the devices in a mirror or raidz configuration.

	   new_device  is required if the pool is not redundant. If new_device
	   is not specified, it defaults to old_device. This form of  replace-
	   ment is useful after an existing disk has failed and has been phys-
	   ically replaced. In this case, the  new  disk  may  have  the  same
	   /dev/dsk  path as the old device, even though it is actually a dif-
	   ferent disk. ZFS recognizes this.

	   -f	 Forces use of new_device, even if its appears to be  in  use.
		 Not all devices can be overridden in this manner.

       zpool scrub [-s] pool ...

	   Begins  a scrub. The scrub examines all data in the specified pools
	   to verify that it checksums correctly. For  replicated  (mirror  or
	   raidz)  devices,  ZFS  automatically  repairs any damage discovered
	   during the scrub. The "zpool status" command reports  the  progress
	   of  the  scrub and summarizes the results of the scrub upon comple-
	   tion.

	   Scrubbing and resilvering are very similar operations. The  differ-
	   ence  is  that  resilvering only examines data that ZFS knows to be
	   out of date (for example, when attaching a new device to  a	mirror
	   or  replacing  an  existing device), whereas scrubbing examines all
	   data to discover silent errors due to hardware faults or disk fail-
	   ure.

	   Because scrubbing and resilvering are I/O-intensive operations, ZFS
	   only allows one at a time. If a scrub is already in	progress,  the
	   "zpool  scrub"  command  terminates it and starts a new scrub. If a
	   resilver is in progress, ZFS does not allow a scrub to  be  started
	   until the resilver completes.

	   -s	 Stop scrubbing.

       zpool set property=value pool

	   Sets the given property on the specified pool. See the "Properties"
	   section for more information on what  properties  can  be  set  and
	   acceptable values.

       zpool status [-xv] [pool] ...

	   Displays the detailed health status for the given pools. If no pool
	   is specified, then the status of each pool in the  system  is  dis-
	   played.  For  more  information  on pool and device health, see the
	   "Device Failure and Recovery" section.

	   If a scrub or resilver is in progress,  this  command  reports  the
	   percentage done and the estimated time to completion. Both of these
	   are only approximate, because the amount of data in	the  pool  and
	   the other workloads on the system can change.

	   -x	 Only  display	status for pools that are exhibiting errors or
		 are otherwise unavailable.

	   -v	 Displays verbose data error information, printing out a  com-
		 plete	list  of  all data errors since the last complete pool
		 scrub.

       zpool upgrade

	   Displays all pools formatted using a different ZFS on-disk version.
	   Older  versions  can continue to be used, but some features may not
	   be available. These pools can be upgraded using "zpool upgrade -a".
	   Pools  that	are formatted with a more recent version are also dis-
	   played, although these pools will be inaccessible on the system.

       zpool upgrade -v

	   Displays ZFS versions supported by the current software.  The  cur-
	   rent  ZFS  versions	and  all  previous supported versions are dis-
	   played, along with an explanation of  the  features	provided  with
	   each version.

       zpool upgrade [-V version] -a | pool ...

	   Upgrades the given pool to the latest on-disk version. Once this is
	   done, the pool will no longer  be  accessible  on  systems  running
	   older versions of the software.

	   -a		 Upgrades all pools.

	   -V version	 Upgrade  to  the specified version. If the -V flag is
			 not specified, the  pool  is  upgraded  to  the  most
			 recent  version.  This  option  can  only  be used to
			 increase the version number, and only up to the  most
			 recent version supported by this software.

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 c0t0d0 c0t1d0 c0t2d0 c0t3d0 c0t4d0 c0t5d0

       Example 2 Creating a Mirrored Storage Pool

       The following command creates a pool with two mirrors, where each  mir-
       ror 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 pur-
       poses.

	 # 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 con-
       tained 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
		     c1t2d0  ONLINE
		     c1t3d0  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 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

       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 c0d0 c1d0 mirror c2d0 c3d0 log mirror \
	    c4d0 c5d0

       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 c2d0 c3d0

       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 option as follows:

	 # zpool iostat -v pool 5

       Example 14 Removing a Mirrored Log Device

       The following command removes the mirrored log device mirror-2.

       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
		      c6t0d0  ONLINE	   0	 0     0
		      c6t1d0  ONLINE	   0	 0     0
		    mirror-1  ONLINE	   0	 0     0
		      c6t2d0  ONLINE	   0	 0     0
		      c6t3d0  ONLINE	   0	 0     0
		  logs
		    mirror-2  ONLINE	   0	 0     0
		      c4t0d0  ONLINE	   0	 0     0
		      c4t1d0  ONLINE	   0	 0     0

       The command to remove the mirrored log mirror-2 is:

	 # zpool remove tank mirror-2

EXIT STATUS
       The following exit values are returned:

       0    Successful completion.

       1    An error occurred.

       2    Invalid command line options were specified.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWzfsu			   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       zfs(1M), attributes(5)

SunOS 5.11			  21 Sep 2009			     zpool(1M)

NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | EXIT STATUS | ATTRIBUTES | SEE ALSO

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