zpool

ZPOOL(8) System Manager's Manual ZPOOL(8)

NAME

   zpool  configure ZFS storage pools

SYNOPSIS

   zpool -?V
   zpool version [-j]
   zpool subcommand [arguments]

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 [-j]
           Displays the software version of the zpool userland utility and the ZFS kernel module.  Use -j option to output in JSON format.

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)
           Converts a non-redundant disk into a mirror, or increases the redundancy level of an existing mirror (attach), or performs the inverse operation ( detach).

   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/O operations 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  de
           vice 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-prefetch(8)
           Prefetches specific types of pool data.

   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 report
           ing.  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 a non-redundant pool using two disk partitions:
         # zpool create tank sda1 sdb2

Example 4: Creating a ZFS Storage Pool by Using Files

   The following command creates a non-redundant 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: Making a non-mirrored ZFS Storage Pool mirrored

   The following command converts an existing single device sda into a mirror by attaching a second device to it, sdb.
         # zpool attach tank sda sdb

Example 6: 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 7: 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  fol
   lowing:
         # 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 8: Destroying a ZFS Storage Pool

   The following command destroys the pool tank and any datasets contained within:
         # zpool destroy -f tank

Example 9: 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 10: 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 11: 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 12: 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 13: 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 14: 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 15: 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

   At this point, the log device no longer exists (both sides of the mirror have been removed):
           pool: tank
          state: ONLINE
           scan: 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

   The command to remove the mirrored data mirror-1 is:
         # zpool remove tank mirror-1

   After mirror-1 has been evacuated, the pool remains redundant, but the total amount of space is reduced:
           pool: tank
          state: ONLINE
           scan: 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

Example 16: 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  10  GiB.
   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 17: 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 and zpool iostat output.
   ZPOOL_AUTO_POWER_ON_SLOT               Automatically attempt to turn on the drives enclosure slot power to a drive when running the zpool online or zpool clear commands.  This has the
                                          same effect as passing the --power option to those commands.
   ZPOOL_POWER_ON_SLOT_TIMEOUT_MS         The  maximum time in milliseconds to wait for a slot power sysfs value to return the correct value after writing it.  For example, after writing
                                          "on" to the sysfs enclosure slot power_control file, it can take some time for the enclosure to power down the slot and return "on" if you  read
                                          back the 'power_control' value.  Defaults to 30 seconds (30000ms) if not set.
   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 mat
                                          ters.
   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 con‐
                                          fig.  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.
   ZFS_MODULE_TIMEOUT                     Time, in seconds, to wait for /dev/zfs to appear.  Defaults to 10, max 600 (10 minutes).  If <0, wait forever; if 0, don't wait.

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-ddtprune(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-prefetch(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)

OpenZFS February 14, 2024 ZPOOL(8)