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40 .Nd configures ZFS file systems
47 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ... Ar filesystem
52 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
58 .Ar filesystem Ns | Ns Ar volume
63 .Ar filesystem Ns | Ns volume
66 .Op , Ns Ar snap Op % Ns Ar snap
71 .Ar filesystem Ns | Ns Ar volume Ns # Ns Ar bookmark
73 .Cm snapshot Ns | Ns Cm snap
75 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
76 .Ar filesystem@snapname Ns | Ns Ar volume@snapname
77 .Ar filesystem@snapname Ns | Ns Ar volume@snapname Ns ...
85 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
86 .Ar snapshot filesystem Ns | Ns Ar volume
93 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
94 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
99 .Ar filesystem Ns | Ns Ar volume
100 .Ar filesystem Ns | Ns Ar volume
104 .Ar snapshot snapshot
107 .Ar bookmark bookmark
112 .Ar filesystem filesystem
115 .Op Fl r Ns | Ns Fl d Ar depth
117 .Op Fl o Ar property Ns Oo , Ns property Ns Oc Ns ...
118 .Op Fl t Ar type Ns Oo , Ns type Ns Oc Ns ...
119 .Oo Fl s Ar property Oc Ns ...
120 .Oo Fl S Ar property Oc Ns ...
121 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot | Ns Ar bookmark Ns ...
124 .Ar filesystem Ns | Ns Ar volume
127 .Ar property Ns = Ns Ar value Oo Ar property Ns = Ns Ar value Oc Ns ...
128 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
131 .Op Fl r Ns | Ns Fl d Ar depth
133 .Op Fl o Ar all | field Ns Oo , Ns Ar field Oc Ns ...
134 .Op Fl t Ar type Ns Oo Ns , Ar type Oc Ns ...
135 .Op Fl s Ar source Ns Oo Ns , Ns Ar source Oc Ns ...
136 .Ar all | property Ns Oo Ns , Ns Ar property Oc Ns ...
137 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
142 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
150 .Fl a | Ar filesystem
154 .Op Fl o Ar field Ns Oo , Ns Ar field Oc Ns ...
155 .Oo Fl s Ar field Oc Ns ...
156 .Oo Fl S Ar field Oc Ns ...
157 .Op Fl t Ar type Ns Oo Ns , Ns Ar type Oc Ns ...
158 .Ar filesystem Ns | Ns Ar snapshot
162 .Op Fl o Ar field Ns Oo , Ns field Oc Ns ...
163 .Oo Fl s Ar field Oc Ns ...
164 .Oo Fl S Ar field Oc Ns ...
165 .Op Fl t Ar type Ns Oo Ns , Ns Ar type Oc Ns ...
166 .Ar filesystem Ns | Ns Ar snapshot
172 .Op Fl o Ar property Ns Oo , Ns Ar property Oc Ns ...
173 .Fl a | Ar filesystem
175 .Cm unmount Ns | Ns Cm umount
177 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
180 .Fl a | Ar filesystem
183 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
191 .Op Fl i Ar snapshot | Fl I Ar snapshot
196 .Op Fl i Ar snapshot Ns | Ns Ar bookmark
197 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
201 .Fl t Ar receive_resume_token
203 .Cm receive Ns | Ns Cm recv
205 .Op Fl o Sy origin Ns = Ns Ar snapshot
206 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
208 .Cm receive Ns | Ns Cm recv
211 .Op Fl o Sy origin Ns = Ns Ar snapshot
214 .Cm receive Ns | Ns Cm recv
216 .Ar filesystem Ns | Ns Ar volume
219 .Ar filesystem Ns | Ns Ar volume
223 .Ar user Ns | Ns Ar group Ns Oo Ns , Ns Ar user Ns | Ns Ar group Oc Ns ...
224 .Ar perm Ns | Ns Ar @setname Ns
225 .Oo Ns , Ns Ar perm Ns | Ns Ar @setname Oc Ns ...
226 .Ar filesystem Ns | Ns Ar volume
230 .Fl e Ns | Ns Cm everyone
231 .Ar perm Ns | Ns Ar @setname Ns Op Ns , Ns Ar perm Ns | Ns Ar @setname Ns
233 .Ar filesystem Ns | Ns Ar volume
237 .Ar perm Ns | Ns Ar @setname Ns Op Ns , Ns Ar perm Ns | Ns Ar @setname Ns
239 .Ar filesystem Ns | Ns Ar volume
244 .Ar perm Ns | Ns Ar @setname Ns Op Ns , Ns Ar perm Ns | Ns Ar @setname Ns
246 .Ar filesystem Ns | Ns Ar volume
250 .Ar user Ns | Ns Ar group Ns Oo Ns , Ns Ar user Ns | Ns Ar group Oc Ns ...
251 .Oo Ar perm Ns | Ns Ar @setname Ns Op , Ns Ar perm Ns | Ns Ar @setname Ns
253 .Ar filesystem Ns | Ns Ar volume
257 .Fl e Ns | Ns Cm everyone
258 .Oo Ar perm Ns | Ns Ar @setname Ns Op , Ns Ar perm Ns | Ns Ar @setname Ns
260 .Ar filesystem Ns | Ns Ar volume
265 .Oo Ar perm Ns | Ns Ar @setname Ns Op , Ns Ar perm Ns | Ns Ar @setname Ns
267 .Ar filesystem Ns | Ns Ar volume
273 .Oo Ar perm Ns | Ns Ar @setname Ns Op , Ns Ar perm Ns | Ns Ar @setname Ns
275 .Ar filesystem Ns | Ns Ar volume
279 .Ar tag snapshot Ns ...
283 .Op Fl r Ns | Ns Fl d Ar depth
284 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns
289 .Ar tag snapshot Ns ...
294 .Op Ar snapshot Ns | Ns Ar filesystem
299 .Op Fl m Ar memory_limit
304 .Ar jailid Ns | Ns Ar jailname filesystem
307 .Ar jailid Ns | Ns Ar jailname filesystem
315 storage pool, as described in
317 A dataset is identified by a unique path within the
319 namespace. For example:
320 .Bd -ragged -offset 4n
321 .No pool/ Ns Brq filesystem,volume,snapshot
324 where the maximum length of a dataset name is
327 and the maximum amount of nesting allowed in a path is 50 levels deep.
329 A dataset can be one of the following:
336 can be mounted within the standard system namespace and behaves like other file
339 file systems are designed to be
341 compliant, known issues exist that prevent compliance in some cases.
342 Applications that depend on standards conformance might fail due to nonstandard
343 behavior when checking file system free space.
345 A logical volume exported as a raw or block device. This type of dataset should
346 only be used under special circumstances. File systems are typically used in
349 A read-only version of a file system or volume at a given point in time. It is
355 .Ss ZFS File System Hierarchy
358 storage pool is a logical collection of devices that provide space for
359 datasets. A storage pool is also the root of the
361 file system hierarchy.
363 The root of the pool can be accessed as a file system, such as mounting and
364 unmounting, taking snapshots, and setting properties. The physical storage
365 characteristics, however, are managed by the
371 for more information on creating and administering pools.
373 A snapshot is a read-only copy of a file system or volume. Snapshots can be
374 created extremely quickly, and initially consume no additional space within the
375 pool. As data within the active dataset changes, the snapshot consumes more
376 data than would otherwise be shared with the active dataset.
378 Snapshots can have arbitrary names. Snapshots of volumes can be cloned or
379 rolled back, but cannot be accessed independently.
381 File system snapshots can be accessed under the
383 directory in the root of the file system. Snapshots are automatically mounted
384 on demand and may be unmounted at regular intervals. The visibility of the
386 directory can be controlled by the
390 A clone is a writable volume or file system whose initial contents are the same
391 as another dataset. As with snapshots, creating a clone is nearly
392 instantaneous, and initially consumes no additional space.
394 Clones can only be created from a snapshot. When a snapshot is cloned, it
395 creates an implicit dependency between the parent and child. Even though the
396 clone is created somewhere else in the dataset hierarchy, the original snapshot
397 cannot be destroyed as long as a clone exists. The
399 property exposes this dependency, and the
401 command lists any such dependencies, if they exist.
403 The clone parent-child dependency relationship can be reversed by using the
405 subcommand. This causes the "origin" file system to become a clone of the
406 specified file system, which makes it possible to destroy the file system that
407 the clone was created from.
411 file system is a simple operation, so the number of file systems per system is
412 likely to be numerous. To cope with this,
414 automatically manages mounting and unmounting file systems without the need to
417 file. All automatically managed file systems are mounted by
421 By default, file systems are mounted under
425 is the name of the file system in the
427 namespace. Directories are created and destroyed as needed.
429 A file system can also have a mount point set in the
431 property. This directory is created as needed, and
433 automatically mounts the file system when the
435 command is invoked (without editing
439 property can be inherited, so if
445 automatically inherits a mount point of
452 prevents the file system from being mounted.
456 file systems can also be managed with traditional tools
457 .Pq Xr mount 8 , Xr umount 8 , Xr fstab 5 .
458 If a file system's mount point is set to
461 makes no attempt to manage the file system, and the administrator is
462 responsible for mounting and unmounting the file system.
465 dataset can be attached to a jail by using the
467 subcommand. You cannot attach a dataset to one jail and the children of the
468 same dataset to another jail. You can also not attach the root file system
469 of the jail or any dataset which needs to be mounted before the zfs rc script
470 is run inside the jail, as it would be attached unmounted until it is
471 mounted from the rc script inside the jail. To allow management of the
472 dataset from within a jail, the
474 property has to be set and the jail needs access to the
478 property cannot be changed from within a jail. See
480 for information on how to allow mounting
482 datasets from within a jail.
485 dataset can be detached from a jail using the
489 After a dataset is attached to a jail and the jailed property is set, a jailed
490 file system cannot be mounted outside the jail, since the jail administrator
491 might have set the mount point to an unacceptable value.
493 Deduplication is the process for removing redundant data at the block-level,
494 reducing the total amount of data stored. If a file system has the
496 property enabled, duplicate data blocks are removed synchronously. The result
497 is that only unique data is stored and common components are shared among
499 .Ss Native Properties
500 Properties are divided into two types, native properties and user-defined (or
501 "user") properties. Native properties either export internal statistics or
504 behavior. In addition, native properties are either editable or read-only. User
505 properties have no effect on
507 behavior, but you can use them to annotate datasets in a way that is meaningful
508 in your environment. For more information about user properties, see the
509 .Qq Sx User Properties
512 Every dataset has a set of properties that export statistics about the dataset
513 as well as control various behaviors. Properties are inherited from the parent
514 unless overridden by the child. Some properties apply only to certain types of
515 datasets (file systems, volumes, or snapshots).
517 The values of numeric properties can be specified using human-readable suffixes
519 .Sy k , KB , M , Gb ,
522 for zettabyte). The following are all valid (and equal) specifications:
523 .Bd -ragged -offset 4n
527 The values of non-numeric properties are case sensitive and must be lowercase,
529 .Sy mountpoint , sharenfs , No and Sy sharesmb .
531 The following native properties consist of read-only statistics about the
532 dataset. These properties can be neither set, nor inherited. Native properties
533 apply to all dataset types unless otherwise noted.
536 The amount of space available to the dataset and all its children, assuming
537 that there is no other activity in the pool. Because space is shared within a
538 pool, availability can be limited by any number of factors, including physical
539 pool size, quotas, reservations, or other datasets within the pool.
541 This property can also be referred to by its shortened column name,
544 For non-snapshots, the compression ratio achieved for the
546 space of this dataset, expressed as a multiplier. The
548 property includes descendant datasets, and, for clones, does not include
549 the space shared with the origin snapshot. For snapshots, the
553 property. Compression can be turned on by running:
554 .Qq Nm Cm set compression=on Ar dataset
558 The transaction group (txg) in which the dataset was created.
559 Bookmarks have the same
561 as the snapshot they are initially tied to.
562 This property is suitable for ordering a list of snapshots,
563 e.g. for incremental send and receive.
565 The time this dataset was created.
567 For snapshots, this property is a comma-separated list of filesystems or
568 volumes which are clones of this snapshot. The clones'
570 property is this snapshot. If the
572 property is not empty, then this snapshot can not be destroyed (even with the
580 if the snapshot has been marked for deferred destroy by using the
582 command. Otherwise, the property is
584 .It Sy filesystem_count
585 The total number of filesystems and volumes that exist under this location in the
587 This value is only available when a
590 been set somewhere in the tree under which the dataset resides.
592 The 64 bit GUID of this dataset or bookmark which does not change over its
594 When a snapshot is sent to another pool, the received snapshot has the same
598 is suitable to identify a snapshot across pools.
599 .It Sy logicalreferenced
600 The amount of space that is
602 accessible by this dataset.
606 The logical space ignores the effect of the
610 properties, giving a quantity closer to the amount of data that applications
612 However, it does include space consumed by metadata.
614 This property can also be referred to by its shortened column name,
617 The amount of space that is
619 consumed by this dataset and all its descendents.
623 The logical space ignores the effect of the
627 properties, giving a quantity closer to the amount of data that applications
630 This property can also be referred to by its shortened column name,
633 For file systems, indicates whether the file system is currently mounted. This
634 property can be either
639 For cloned file systems or volumes, the snapshot from which the clone was
640 created. See also the
643 .It Sy receive_resume_token
644 For filesystems or volumes which have saved partially-completed state from
646 this opaque token can be provided to
648 to resume and complete the
651 The amount of data that is accessible by this dataset, which may or may not be
652 shared with other datasets in the pool. When a snapshot or clone is created, it
653 initially references the same amount of space as the file system or snapshot it
654 was created from, since its contents are identical.
656 This property can also be referred to by its shortened column name,
658 .It Sy refcompressratio
659 The compression ratio achieved for the
661 space of this dataset, expressed as a multiplier. See also the
664 .It Sy snapshot_count
665 The total number of snapshots that exist under this location in the dataset tree.
666 This value is only available when a
668 has been set somewhere
669 in the tree under which the dataset resides.
672 .Sy filesystem , volume , No or Sy snapshot .
674 The amount of space consumed by this dataset and all its descendents. This is
675 the value that is checked against this dataset's quota and reservation. The
676 space used does not include this dataset's reservation, but does take into
677 account the reservations of any descendent datasets. The amount of space that a
678 dataset consumes from its parent, as well as the amount of space that are freed
679 if this dataset is recursively destroyed, is the greater of its space used and
682 When snapshots (see the
684 section) are created, their space is
685 initially shared between the snapshot and the file system, and possibly with
686 previous snapshots. As the file system changes, space that was previously
687 shared becomes unique to the snapshot, and counted in the snapshot's space
688 used. Additionally, deleting snapshots can increase the amount of space unique
689 to (and used by) other snapshots.
691 The amount of space used, available, or referenced does not take into account
692 pending changes. Pending changes are generally accounted for within a few
693 seconds. Committing a change to a disk using
697 does not necessarily guarantee that the space usage information is updated
702 properties decompose the
704 properties into the various reasons that space is used. Specifically,
706 .Sy usedbysnapshots + usedbydataset + usedbychildren + usedbyrefreservation .
707 These properties are only available for datasets created
710 pool version 13 pools and higher.
711 .It Sy usedbysnapshots
712 The amount of space consumed by snapshots of this dataset. In particular, it is
713 the amount of space that would be freed if all of this dataset's snapshots were
714 destroyed. Note that this is not simply the sum of the snapshots'
716 properties because space can be shared by multiple snapshots.
718 The amount of space used by this dataset itself, which would be freed if the
719 dataset were destroyed (after first removing any
721 and destroying any necessary snapshots or descendents).
722 .It Sy usedbychildren
723 The amount of space used by children of this dataset, which would be freed if
724 all the dataset's children were destroyed.
725 .It Sy usedbyrefreservation
726 The amount of space used by a
728 set on this dataset, which would be freed if the
731 .It Sy userused@ Ns Ar user
732 The amount of space consumed by the specified user in this dataset. Space is
733 charged to the owner of each file, as displayed by
735 The amount of space charged is displayed by
741 subcommand for more information.
743 Unprivileged users can access only their own space usage. The root user, or a
744 user who has been granted the
748 can access everyone's usage.
752 properties are not displayed by
754 The user's name must be appended after the
756 symbol, using one of the following forms:
757 .Bl -bullet -offset 2n
759 POSIX name (for example,
762 POSIX numeric ID (for example,
766 This property is set to the number of user holds on this snapshot. User holds
770 .It Sy groupused@ Ns Ar group
771 The amount of space consumed by the specified group in this dataset. Space is
772 charged to the group of each file, as displayed by
775 .Sy userused@ Ns Ar user
776 property for more information.
778 Unprivileged users can only access their own groups' space usage. The root
779 user, or a user who has been granted the
783 can access all groups' usage.
784 .It Sy volblocksize Ns = Ns Ar blocksize
785 For volumes, specifies the block size of the volume. The
787 cannot be changed once the volume has been written, so it should be set at
788 volume creation time. The default
790 for volumes is 8 Kbytes. Any
791 power of 2 from 512 bytes to 128 Kbytes is valid.
793 This property can also be referred to by its shortened column name,
798 space written to this dataset since the previous snapshot.
799 .It Sy written@ Ns Ar snapshot
802 space written to this dataset since the specified snapshot. This is the space
803 that is referenced by this dataset but was not referenced by the specified
808 may be specified as a short snapshot name (just the part after the
810 in which case it will be interpreted as a snapshot in the same filesystem as
813 may be a full snapshot name
814 .Pq Em filesystem@snapshot ,
815 which for clones may be a snapshot in the origin's filesystem (or the origin of
816 the origin's filesystem, etc).
819 The following native properties can be used to change the behavior of a
824 .Sy aclinherit Ns = Ns Cm discard |
832 entries are inherited when files and directories are created. A file system
839 entries. A file system with an
843 only inherits inheritable
845 entries that specify "deny" permissions. The property value
847 (the default) removes the
853 entry is inherited. A file system with an
857 inherits all inheritable
859 entries without any modifications made to the
861 entries when they are inherited. A file system with an
865 has the same meaning as
868 .Em owner@ , group@ , No and Em everyone@ Tn ACE Ns s
869 inherit the execute permission only if the file creation mode also requests the
872 When the property value is set to
874 files are created with a mode determined by the inheritable
878 exist that affect the mode, then the mode is set in accordance to the requested
879 mode from the application.
880 .It Sy aclmode Ns = Ns Cm discard | groupmask | passthrough | restricted
885 A file system with an
889 (the default) deletes all
891 entries that do not represent the mode of the file. An
895 reduces permissions granted in all
899 such that they are no greater than the group permissions specified by
901 A file system with an
905 indicates that no changes are made to the
907 other than creating or updating the necessary
909 entries to represent the new mode of the file or directory.
916 operation to return an error when used on any file or directory which has
919 whose entries can not be represented by a mode.
921 is required to change the set user ID, set group ID, or sticky bits on a file
922 or directory, as they do not have equivalent
927 on a file or directory with a non-trivial
933 you must first remove all
935 entries which do not represent the current mode.
936 .It Sy atime Ns = Ns Cm on | off
937 Controls whether the access time for files is updated when they are read.
938 Turning this property off avoids producing write traffic when reading files and
939 can result in significant performance gains, though it might confuse mailers
940 and other similar utilities. The default value is
942 .It Sy canmount Ns = Ns Cm on | off | noauto
943 If this property is set to
945 the file system cannot be mounted, and is ignored by
946 .Qq Nm Cm mount Fl a .
947 Setting this property to
949 is similar to setting the
953 except that the dataset still has a normal
955 property, which can be inherited. Setting this property to
957 allows datasets to be used solely as a mechanism to inherit properties. One
959 .Sy canmount Ns = Ns Cm off
960 is to have two datasets with the same
962 so that the children of both datasets appear in the same directory, but might
963 have different inherited characteristics.
967 value is set, a dataset can only be mounted and unmounted explicitly. The
968 dataset is not mounted automatically when the dataset is created or imported,
969 nor is it mounted by the
971 command or unmounted by the
972 .Qq Nm Cm umount Fl a
975 This property is not inherited.
976 .It Sy checksum Ns = Ns Cm on | off | fletcher2 | fletcher4 | sha256 | noparity | sha512 | skein
977 Controls the checksum used to verify data integrity. The default value is
979 which automatically selects an appropriate algorithm (currently,
981 but this may change in future releases). The value
983 disables integrity checking on user data.
987 disables integrity but also disables maintaining parity for user data. This
988 setting is used internally by a dump device residing on a RAID-Z pool and should
989 not be used by any other dataset.
990 Disabling checksums is
992 a recommended practice.
997 checksum algorithms require enabling the appropriate features on the pool.
1000 for more information on these algorithms.
1002 Changing this property affects only newly-written data.
1004 Salted checksum algorithms
1005 .Pq Cm edonr , skein
1006 are currently not supported for any filesystem on the boot pools.
1007 .It Sy compression Ns = Ns Cm on | off | lzjb | gzip | gzip- Ns Ar N | Cm zle | Cm lz4
1008 Controls the compression algorithm used for this dataset.
1009 Setting compression to
1011 indicates that the current default compression algorithm should be used.
1012 The default balances compression and decompression speed, with compression
1013 ratio and is expected to work well on a wide variety of workloads.
1014 Unlike all other settings for this property, on does not select a fixed
1016 As new compression algorithms are added to ZFS and enabled on a pool, the
1017 default compression algorithm may change.
1018 The current default compression algorthm is either
1026 compression algorithm is optimized for performance while providing decent data
1027 compression. Setting compression to
1031 compression algorithm. The
1033 compression algorithm uses the same compression as the
1035 command. You can specify the
1037 level by using the value
1041 is an integer from 1 (fastest) to 9 (best compression ratio). Currently,
1045 (which is also the default for
1049 compression algorithm compresses runs of zeros.
1053 compression algorithm is a high-performance replacement
1056 algorithm. It features significantly faster
1057 compression and decompression, as well as a moderately higher
1058 compression ratio than
1060 but can only be used on pools with
1066 .Xr zpool-features 7
1067 for details on ZFS feature flags and the
1071 This property can also be referred to by its shortened column name
1073 Changing this property affects only newly-written data.
1074 .It Sy copies Ns = Ns Cm 1 | 2 | 3
1075 Controls the number of copies of data stored for this dataset. These copies are
1076 in addition to any redundancy provided by the pool, for example, mirroring or
1077 RAID-Z. The copies are stored on different disks, if possible. The space used
1078 by multiple copies is charged to the associated file and dataset, changing the
1080 property and counting against quotas and reservations.
1082 Changing this property only affects newly-written data. Therefore, set this
1083 property at file system creation time by using the
1084 .Fl o Cm copies= Ns Ar N
1086 .It Sy dedup Ns = Ns Cm on | off | verify | sha256 Ns Oo Cm ,verify Oc | Sy sha512 Ns Oo Cm ,verify Oc | Sy skein Ns Oo Cm ,verify Oc
1087 Configures deduplication for a dataset. The default value is
1089 The default deduplication checksum is
1091 (this may change in the future).
1094 is enabled, the checksum defined here overrides the
1096 property. Setting the value to
1098 has the same effect as the setting
1104 will do a byte-to-byte comparsion in case of two blocks having the same
1105 signature to make sure the block contents are identical.
1106 .It Sy devices Ns = Ns Cm on | off
1109 property is currently not supported on
1111 .It Sy exec Ns = Ns Cm on | off
1112 Controls whether processes can be executed from within this file system. The
1115 .It Sy mlslabel Ns = Ns Ar label | Cm none
1118 property is currently not supported on
1120 .It Sy filesystem_limit Ns = Ns Ar count | Cm none
1121 Limits the number of filesystems and volumes that can exist under this point in
1123 The limit is not enforced if the user is allowed to change
1126 .Sy filesystem_limit
1127 on a descendent of a filesystem that
1129 .Sy filesystem_limit
1130 does not override the ancestor's
1131 .Sy filesystem_limit ,
1132 but rather imposes an additional limit.
1133 This feature must be enabled to be used
1135 .Xr zpool-features 7
1137 .It Sy special_small_blocks Ns = Ns Ar size
1138 This value represents the threshold block size for including small file
1139 blocks into the special allocation class.
1140 Blocks smaller than or equal to this value will be assigned to the special
1141 allocation class while greater blocks will be assigned to the regular class.
1142 Valid values are zero or a power of two from 512B up to 128K.
1143 The default size is 0 which means no small file blocks will be allocated in
1146 Before setting this property, a special class vdev must be added to the
1150 for more details on the special allocation class.
1151 .It Sy mountpoint Ns = Ns Ar path | Cm none | legacy
1152 Controls the mount point used for this file system.
1155 section for more information on how this property is used.
1159 property is changed for a file system, the file system and any children that
1160 inherit the mount point are unmounted. If the new value is
1162 then they remain unmounted. Otherwise, they are automatically remounted in the
1163 new location if the property was previously
1167 or if they were mounted before the property was changed. In addition, any
1168 shared file systems are unshared and shared in the new location.
1169 .It Sy nbmand Ns = Ns Cm on | off
1172 property is currently not supported on
1174 .It Sy primarycache Ns = Ns Cm all | none | metadata
1175 Controls what is cached in the primary cache (ARC). If this property is set to
1177 then both user data and metadata is cached. If this property is set to
1179 then neither user data nor metadata is cached. If this property is set to
1181 then only metadata is cached. The default value is
1183 .It Sy quota Ns = Ns Ar size | Cm none
1184 Limits the amount of space a dataset and its descendents can consume. This
1185 property enforces a hard limit on the amount of space used. This includes all
1186 space consumed by descendents, including file systems and snapshots. Setting a
1187 quota on a descendent of a dataset that already has a quota does not override
1188 the ancestor's quota, but rather imposes an additional limit.
1190 Quotas cannot be set on volumes, as the
1192 property acts as an implicit quota.
1193 .It Sy snapshot_limit Ns = Ns Ar count | Cm none
1194 Limits the number of snapshots that can be created on a dataset and its
1198 on a descendent of a dataset that already
1201 does not override the ancestor's
1202 .Sy snapshot_limit ,
1204 rather imposes an additional limit.
1205 The limit is not enforced if the user is
1206 allowed to change the limit.
1207 For example, this means that recursive snapshots
1208 taken from the global zone are counted against each delegated dataset within
1210 This feature must be enabled to be used
1212 .Xr zpool-features 7
1214 .It Sy userquota@ Ns Ar user Ns = Ns Ar size | Cm none
1215 Limits the amount of space consumed by the specified user.
1220 space calculation does not include space that is used by descendent datasets,
1221 such as snapshots and clones. User space consumption is identified by the
1222 .Sy userspace@ Ns Ar user
1225 Enforcement of user quotas may be delayed by several seconds. This delay means
1226 that a user might exceed their quota before the system notices that they are
1227 over quota and begins to refuse additional writes with the
1229 error message. See the
1231 subcommand for more information.
1233 Unprivileged users can only access their own groups' space usage. The root
1234 user, or a user who has been granted the
1238 can get and set everyone's quota.
1240 This property is not available on volumes, on file systems before version 4, or
1241 on pools before version 15. The
1242 .Sy userquota@ Ns ...
1243 properties are not displayed by
1245 The user's name must be appended after the
1247 symbol, using one of the following forms:
1248 .Bl -bullet -offset 2n
1250 POSIX name (for example,
1253 POSIX numeric ID (for example,
1256 .It Sy groupquota@ Ns Ar group Ns = Ns Ar size | Cm none
1257 Limits the amount of space consumed by the specified group. Group space
1258 consumption is identified by the
1259 .Sy userquota@ Ns Ar user
1262 Unprivileged users can access only their own groups' space usage. The root
1263 user, or a user who has been granted the
1267 can get and set all groups' quotas.
1268 .It Sy readonly Ns = Ns Cm on | off
1269 Controls whether this dataset can be modified. The default value is
1271 .It Sy recordsize Ns = Ns Ar size
1272 Specifies a suggested block size for files in the file system. This property is
1273 designed solely for use with database workloads that access files in fixed-size
1276 automatically tunes block sizes according to internal algorithms optimized for
1277 typical access patterns.
1279 For databases that create very large files but access them in small random
1280 chunks, these algorithms may be suboptimal. Specifying a
1282 greater than or equal to the record size of the database can result in
1283 significant performance gains. Use of this property for general purpose file
1284 systems is strongly discouraged, and may adversely affect performance.
1286 The size specified must be a power of two greater than or equal to 512 and less
1287 than or equal to 128 Kbytes.
1290 feature is enabled on the pool, the size may be up to 1 Mbyte.
1292 .Xr zpool-features 7
1293 for details on ZFS feature flags.
1295 Changing the file system's
1297 affects only files created afterward; existing files are unaffected.
1299 This property can also be referred to by its shortened column name,
1301 .It Sy redundant_metadata Ns = Ns Cm all | most
1302 Controls what types of metadata are stored redundantly.
1303 ZFS stores an extra copy of metadata, so that if a single block is corrupted,
1304 the amount of user data lost is limited.
1305 This extra copy is in addition to any redundancy provided at the pool level
1306 .Pq e.g. by mirroring or RAID-Z ,
1307 and is in addition to an extra copy specified by the
1310 .Pq up to a total of 3 copies .
1311 For example if the pool is mirrored,
1312 .Cm copies Ns = Ns Ar 2 ,
1314 .Cm redundant_metadata Ns = Ns Ar most ,
1316 stores 6 copies of most metadata, and 4 copies of data and some
1321 ZFS stores an extra copy of all metadata.
1323 single on-disk block is corrupt, at worst a single block of user data
1332 ZFS stores an extra copy of most types of
1334 This can improve performance of random writes, because less
1335 metadata must be written.
1336 In practice, at worst about 100 blocks
1341 of user data can be lost if a single
1342 on-disk block is corrupt.
1343 The exact behavior of which metadata blocks
1344 are stored redundantly may change in future releases.
1346 The default value is
1348 .It Sy refquota Ns = Ns Ar size | Cm none
1349 Limits the amount of space a dataset can consume. This property enforces a hard
1350 limit on the amount of space used. This hard limit does not include space used
1351 by descendents, including file systems and snapshots.
1352 .It Sy refreservation Ns = Ns Ar size | Cm none | Cm auto
1353 The minimum amount of space guaranteed to a dataset, not including its
1354 descendents. When the amount of space used is below this value, the dataset is
1355 treated as if it were taking up the amount of space specified by
1356 .Sy refreservation .
1359 reservation is accounted for in the parent datasets' space used, and counts
1360 against the parent datasets' quotas and reservations.
1364 is set, a snapshot is only allowed if there is enough free pool space outside
1365 of this reservation to accommodate the current number of "referenced" bytes in
1372 a volume is thick provisioned or not sparse.
1373 .Sy refreservation Ns = Cm auto
1374 is only supported on volumes.
1377 in the Native Properties
1378 section for more information about sparse volumes.
1380 This property can also be referred to by its shortened column name,
1382 .It Sy reservation Ns = Ns Ar size | Cm none
1383 The minimum amount of space guaranteed to a dataset and its descendents. When
1384 the amount of space used is below this value, the dataset is treated as if it
1385 were taking up the amount of space specified by its reservation. Reservations
1386 are accounted for in the parent datasets' space used, and count against the
1387 parent datasets' quotas and reservations.
1389 This property can also be referred to by its shortened column name,
1391 .It Sy secondarycache Ns = Ns Cm all | none | metadata
1392 Controls what is cached in the secondary cache (L2ARC). If this property is set
1395 then both user data and metadata is cached. If this property is set to
1397 then neither user data nor metadata is cached. If this property is set to
1399 then only metadata is cached. The default value is
1401 .It Sy setuid Ns = Ns Cm on | off
1402 Controls whether the
1404 bit is respected for the file system. The default value is
1406 .It Sy sharesmb Ns = Ns Cm on | off | Ar opts
1409 property currently has no effect on
1411 .It Sy sharenfs Ns = Ns Cm on | off | Ar opts
1412 Controls whether the file system is shared via
1414 and what options are used. A file system with a
1418 is managed the traditional way via
1420 Otherwise, the file system is automatically shared and unshared with the
1424 commands. If the property is set to
1428 export options are used. Otherwise,
1430 export options are equivalent to the contents of this property. The export
1431 options may be comma-separated. See
1433 for a list of valid options.
1437 property is changed for a dataset, the
1440 .It Sy logbias Ns = Ns Cm latency | throughput
1443 about handling of synchronous requests in this dataset.
1450 will use pool log devices (if configured) to handle the requests at low
1456 will not use configured pool log devices.
1458 will instead optimize synchronous operations for global pool throughput and
1459 efficient use of resources.
1460 .It Sy snapdir Ns = Ns Cm hidden | visible
1461 Controls whether the
1463 directory is hidden or visible in the root of the file system as discussed in
1466 section. The default value is
1468 .It Sy sync Ns = Ns Cm standard | always | disabled
1469 Controls the behavior of synchronous requests (e.g.
1471 O_DSYNC). This property accepts the following values:
1472 .Bl -tag -offset 4n -width 8n
1474 This is the POSIX specified behavior of ensuring all synchronous requests are
1475 written to stable storage and all devices are flushed to ensure data is not
1476 cached by device controllers (this is the default).
1478 All file system transactions are written and flushed before their system calls
1479 return. This has a large performance penalty.
1481 Disables synchronous requests. File system transactions are only committed to
1482 stable storage periodically. This option will give the highest performance.
1483 However, it is very dangerous as
1485 would be ignoring the synchronous transaction demands of applications such as
1488 Administrators should only use this option when the risks are understood.
1490 .It Sy volsize Ns = Ns Ar size
1491 For volumes, specifies the logical size of the volume. By default, creating a
1492 volume establishes a reservation of equal size. For storage pools with a
1493 version number of 9 or higher, a
1495 is set instead. Any changes to
1497 are reflected in an equivalent change to the reservation (or
1498 .Sy refreservation ) .
1501 can only be set to a multiple of
1505 The reservation is kept equal to the volume's logical size to prevent
1506 unexpected behavior for consumers. Without the reservation, the volume could
1507 run out of space, resulting in undefined behavior or data corruption, depending
1508 on how the volume is used. These effects can also occur when the volume size is
1509 changed while it is in use (particularly when shrinking the size). Extreme care
1510 should be used when adjusting the volume size.
1512 Though not recommended, a "sparse volume" (also known as "thin provisioned")
1513 can be created by specifying the
1516 .Qq Nm Cm create Fl V
1517 command, or by changing the value of the
1521 property on pool version 8 or earlier
1523 after the volume has been created.
1524 A "sparse volume" is a volume where the value of
1526 is less then the size of the volume plus the space required to store its
1528 Consequently, writes to a sparse volume can fail with
1530 when the pool is low on space. For a sparse volume, changes to
1532 are not reflected in the
1533 .Sy refreservation .
1534 A volume that is not sparse is said to be "thick provisioned".
1535 A sparse volume can become thick provisioned by setting
1539 .It Sy volmode Ns = Ns Cm default | geom | dev | none
1540 This property specifies how volumes should be exposed to the OS.
1545 providers, providing maximal functionality.
1548 exposes volumes only as cdev device in devfs.
1549 Such volumes can be accessed only as raw disk device files, i.e. they
1550 can not be partitioned, mounted, participate in RAIDs, etc, but they
1551 are faster, and in some use scenarios with untrusted consumer, such as
1552 NAS or VM storage, can be more safe.
1553 Volumes with property set to
1555 are not exposed outside ZFS, but can be snapshoted, cloned, replicated, etc,
1556 that can be suitable for backup purposes.
1559 means that volumes exposition is controlled by system-wide sysctl/tunable
1560 .Va vfs.zfs.vol.mode ,
1566 are encoded as 1, 2 and 3 respectively.
1567 The default values is
1569 This property can be changed any time, but so far it is processed only
1570 during volume creation and pool import.
1571 .It Sy vscan Ns = Ns Cm off | on
1574 property is currently not supported on
1576 .It Sy xattr Ns = Ns Cm off | on
1579 property is currently not supported on
1581 .It Sy jailed Ns = Ns Cm off | on
1582 Controls whether the dataset is managed from a jail. See the
1584 section for more information. The default value is
1588 The following three properties cannot be changed after the file system is
1589 created, and therefore, should be set when the file system is created. If the
1590 properties are not set with the
1594 commands, these properties are inherited from the parent dataset. If the parent
1595 dataset lacks these properties due to having been created prior to these
1596 features being supported, the new file system will have the default values for
1599 .It Sy casesensitivity Ns = Ns Cm sensitive | insensitive | mixed
1600 Indicates whether the file name matching algorithm used by the file system
1601 should be case-sensitive, case-insensitive, or allow a combination of both
1602 styles of matching. The default value for the
1606 Traditionally, UNIX and POSIX file systems have case-sensitive file names.
1612 property indicates that the
1613 file system can support requests for both case-sensitive and case-insensitive
1615 .It Sy normalization Ns = Ns Cm none | formC | formD | formKC | formKD
1616 Indicates whether the file system should perform a
1618 normalization of file names whenever two file names are compared, and which
1619 normalization algorithm should be used. File names are always stored
1620 unmodified, names are normalized as part of any comparison process. If this
1621 property is set to a legal value other than
1625 property was left unspecified, the
1627 property is automatically set to
1629 The default value of the
1633 This property cannot be changed after the file system is created.
1634 .It Sy utf8only Ns = Ns Cm on | off
1635 Indicates whether the file system should reject file names that include
1636 characters that are not present in the
1638 character code set. If this property is explicitly set to
1640 the normalization property must either not be explicitly set or be set to
1642 The default value for the
1646 This property cannot be changed after the file system is created.
1650 .Sy casesensitivity , normalization , No and Sy utf8only
1651 properties are also new permissions that can be assigned to non-privileged
1654 delegated administration feature.
1655 .Ss Temporary Mount Point Properties
1656 When a file system is mounted, either through
1658 for legacy mounts or the
1660 command for normal file systems, its mount options are set according to its
1661 properties. The correlation between properties and mount options is as follows:
1662 .Bl -column -offset 4n "PROPERTY" "MOUNT OPTION"
1663 .It "PROPERTY MOUNT OPTION"
1664 .It "atime atime/noatime"
1665 .It "exec exec/noexec"
1666 .It "readonly ro/rw"
1667 .It "setuid suid/nosuid"
1670 In addition, these options can be set on a per-mount basis using the
1672 option, without affecting the property that is stored on disk. The values
1673 specified on the command line override the values stored in the dataset. These
1674 properties are reported as "temporary" by the
1676 command. If the properties are changed while the dataset is mounted, the new
1677 setting overrides any temporary settings.
1679 In addition to the standard native properties,
1681 supports arbitrary user properties. User properties have no effect on
1683 behavior, but applications or administrators can use them to annotate datasets
1684 (file systems, volumes, and snapshots).
1686 User property names must contain a colon
1688 character to distinguish them from native properties. They may contain
1689 lowercase letters, numbers, and the following punctuation characters: colon
1697 The expected convention is that the property name is divided into two portions
1699 .Em module Ns Sy \&: Ns Em property ,
1700 but this namespace is not enforced by
1702 User property names can be at most 256 characters, and cannot begin with a dash
1705 When making programmatic use of user properties, it is strongly suggested to
1710 component of property names to reduce the chance that two
1711 independently-developed packages use the same property name for different
1712 purposes. Property names beginning with
1714 are reserved for use by Sun Microsystems.
1716 The values of user properties are arbitrary strings, are always inherited, and
1717 are never validated. All of the commands that operate on properties
1724 can be used to manipulate both native properties and user properties. Use the
1726 command to clear a user property. If the property is not defined in any parent
1727 dataset, it is removed entirely. Property values are limited to 1024
1730 All subcommands that modify state are logged persistently to the pool in their
1738 Displays a help message.
1743 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
1749 file system. The file system is automatically mounted according to the
1751 property inherited from the parent.
1752 .Bl -tag -width indent
1754 Creates all the non-existing parent datasets. Datasets created in this manner
1755 are automatically mounted according to the
1757 property inherited from their parent. Any property specified on the command
1760 option is ignored. If the target filesystem already exists, the operation
1761 completes successfully.
1763 Newly created file system is not mounted.
1764 .It Fl o Ar property Ns = Ns Ar value
1765 Sets the specified property as if the command
1766 .Qq Nm Cm set Ar property Ns = Ns Ar value
1767 was invoked at the same time the dataset was created. Any editable
1769 property can also be set at creation time. Multiple
1771 options can be specified. An error results if the same property is specified in
1780 .Op Fl b Ar blocksize
1781 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
1786 Creates a volume of the given size. The volume is exported as a block device in
1787 .Pa /dev/zvol/path ,
1790 is the name of the volume in the
1792 namespace. The size represents the logical size as exported by the device. By
1793 default, a reservation of equal size is created.
1796 is automatically rounded up to the nearest 128 Kbytes to ensure that
1797 the volume has an integral number of blocks regardless of
1799 .Bl -tag -width indent
1801 Creates all the non-existing parent datasets. Datasets created in this manner
1802 are automatically mounted according to the
1804 property inherited from their parent. Any property specified on the command
1807 option is ignored. If the target filesystem already exists, the operation
1808 completes successfully.
1810 Creates a sparse volume with no reservation. See
1813 .Qq Sx Native Properties
1814 section for more information about sparse volumes.
1815 .It Fl b Ar blocksize
1817 .Fl o Cm volblocksize Ns = Ns Ar blocksize .
1818 If this option is specified in conjunction with
1819 .Fl o Cm volblocksize ,
1820 the resulting behavior is undefined.
1821 .It Fl o Ar property Ns = Ns Ar value
1822 Sets the specified property as if the
1823 .Qq Nm Cm set Ar property Ns = Ns Ar value
1824 command was invoked at the same time the dataset was created. Any editable
1826 property can also be set at creation time. Multiple
1828 options can be specified. An error results if the same property is specified in
1837 .Ar filesystem Ns | Ns Ar volume
1840 Destroys the given dataset. By default, the command unshares any file systems
1841 that are currently shared, unmounts any file systems that are currently
1842 mounted, and refuses to destroy a dataset that has active dependents (children
1844 .Bl -tag -width indent
1846 Recursively destroy all children.
1848 Recursively destroy all dependents, including cloned file systems outside the
1851 Force an unmount of any file systems using the
1852 .Qq Nm Cm unmount Fl f
1853 command. This option has no effect on non-file systems or unmounted file
1856 Do a dry-run ("No-op") deletion. No data will be deleted. This is useful in
1857 conjunction with the
1861 flags to determine what data would be deleted.
1863 Print machine-parsable verbose information about the deleted data.
1865 Print verbose information about the deleted data.
1868 Extreme care should be taken when applying either the
1872 options, as they can destroy large portions of a pool and cause unexpected
1873 behavior for mounted file systems in use.
1880 .Op % Ns Ar snapname
1885 The given snapshots are destroyed immediately if and only if the
1889 option would have destroyed it. Such immediate destruction would occur, for
1890 example, if the snapshot had no clones and the user-initiated reference count
1893 If a snapshot does not qualify for immediate destruction, it is marked for
1894 deferred deletion. In this state, it exists as a usable, visible snapshot until
1895 both of the preconditions listed above are met, at which point it is destroyed.
1897 An inclusive range of snapshots may be specified by separating the
1898 first and last snapshots with a percent sign
1900 The first and/or last snapshots may be left blank, in which case the
1901 filesystem's oldest or newest snapshot will be implied.
1904 (or ranges of snapshots) of the same filesystem or volume may be specified
1905 in a comma-separated list of snapshots.
1906 Only the snapshot's short name (the
1909 should be specified when using a range or comma-separated list to identify
1911 .Bl -tag -width indent
1913 Destroy (or mark for deferred deletion) all snapshots with this name in
1914 descendent file systems.
1916 Recursively destroy all clones of these snapshots, including the clones,
1917 snapshots, and children.
1918 If this flag is specified, the
1920 flag will have no effect.
1922 Do a dry-run ("No-op") deletion. No data will be deleted. This is useful in
1923 conjunction with the
1927 flags to determine what data would be deleted.
1929 Print machine-parsable verbose information about the deleted data.
1931 Print verbose information about the deleted data.
1933 Defer snapshot deletion.
1936 Extreme care should be taken when applying either the
1940 options, as they can destroy large portions of a pool and cause unexpected
1941 behavior for mounted file systems in use.
1945 .Ar filesystem Ns | Ns Ar volume Ns # Ns Ar bookmark
1948 The given bookmark is destroyed.
1951 .Cm snapshot Ns | Ns Cm snap
1953 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
1954 .Ar filesystem@snapname Ns | Ns volume@snapname
1955 .Ar filesystem@snapname Ns | Ns volume@snapname Ns ...
1958 Creates snapshots with the given names. All previous modifications by
1959 successful system calls to the file system are part of the snapshots.
1960 Snapshots are taken atomically, so that all snapshots correspond to the same
1961 moment in time. See the
1963 section for details.
1964 .Bl -tag -width indent
1966 Recursively create snapshots of all descendent datasets
1967 .It Fl o Ar property Ns = Ns Ar value
1968 Sets the specified property; see
1979 Roll back the given dataset to a previous snapshot. When a dataset is rolled
1980 back, all data that has changed since the snapshot is discarded, and the
1981 dataset reverts to the state at the time of the snapshot. By default, the
1982 command refuses to roll back to a snapshot other than the most recent one. In
1983 order to do so, all intermediate snapshots and bookmarks must be destroyed
1990 options do not recursively destroy the child snapshots of a
1992 Only direct snapshots of the specified filesystem
1993 are destroyed by either of these options.
1994 To completely roll back a
1995 recursive snapshot, you must rollback the individual child snapshots.
1996 .Bl -tag -width indent
1998 Destroy any snapshots and bookmarks more recent than the one specified.
2000 Destroy any more recent snapshots and bookmarks, as well as any clones of those
2005 option to force an unmount of any clone file systems that are to be destroyed.
2011 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
2012 .Ar snapshot filesystem Ns | Ns Ar volume
2015 Creates a clone of the given snapshot. See the
2017 section for details. The target dataset can be located anywhere in the
2019 hierarchy, and is created as the same type as the original.
2020 .Bl -tag -width indent
2022 Creates all the non-existing parent datasets. Datasets created in this manner
2023 are automatically mounted according to the
2025 property inherited from their parent. If the target filesystem or volume
2026 already exists, the operation completes successfully.
2027 .It Fl o Ar property Ns = Ns Ar value
2028 Sets the specified property; see
2035 .Ar clone-filesystem
2038 Promotes a clone file system to no longer be dependent on its "origin"
2039 snapshot. This makes it possible to destroy the file system that the clone was
2040 created from. The clone parent-child dependency relationship is reversed, so
2041 that the origin file system becomes a clone of the specified file system.
2043 The snapshot that was cloned, and any snapshots previous to this snapshot, are
2044 now owned by the promoted clone. The space they use moves from the origin file
2045 system to the promoted clone, so enough space must be available to accommodate
2046 these snapshots. No new space is consumed by this operation, but the space
2047 accounting is adjusted. The promoted clone must not have any conflicting
2048 snapshot names of its own. The
2050 subcommand can be used to rename any conflicting snapshots.
2055 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2056 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2063 .Ar filesystem Ns | Ns Ar volume
2064 .Ar filesystem Ns | Ns Ar volume
2071 .Ar filesystem filesystem
2074 Renames the given dataset. The new target can be located anywhere in the
2076 hierarchy, with the exception of snapshots. Snapshots can only be renamed
2077 within the parent file system or volume. When renaming a snapshot, the parent
2078 file system of the snapshot does not need to be specified as part of the second
2079 argument. Renamed file systems can inherit new mount points, in which case they
2080 are unmounted and remounted at the new mount point.
2081 .Bl -tag -width indent
2083 Creates all the nonexistent parent datasets. Datasets created in this manner
2084 are automatically mounted according to the
2086 property inherited from their parent.
2088 Do not remount file systems during rename. If a file system's
2094 file system is not unmounted even if this option is not given.
2096 Force unmount any filesystems that need to be unmounted in the process.
2097 This flag has no effect if used together with the
2105 .Ar snapshot snapshot
2108 Recursively rename the snapshots of all descendent datasets. Snapshots are the
2109 only dataset that can be renamed recursively.
2113 .Ar bookmark bookmark
2116 Renames the given bookmark.
2117 Bookmarks can only be renamed within the parent file system or volume.
2118 When renaming a bookmark, the parent file system or volume of the bookmark
2119 does not need to be specified as part of the second argument.
2123 .Op Fl r Ns | Ns Fl d Ar depth
2125 .Op Fl o Ar property Ns Oo , Ns Ar property Oc Ns ...
2126 .Op Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
2127 .Oo Fl s Ar property Oc Ns ...
2128 .Oo Fl S Ar property Oc Ns ...
2129 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
2132 Lists the property information for the given datasets in tabular form. If
2133 specified, you can list property information by the absolute pathname or the
2134 relative pathname. By default, all file systems and volumes are displayed.
2135 Snapshots are displayed if the
2141 The following fields are displayed,
2142 .Sy name , used , available , referenced , mountpoint .
2143 .Bl -tag -width indent
2145 Recursively display any children of the dataset on the command line.
2147 Recursively display any children of the dataset, limiting the recursion to
2151 will display only the dataset and its direct children.
2153 Used for scripting mode. Do not print headers and separate fields by a single
2154 tab instead of arbitrary white space.
2156 Display numbers in parsable (exact) values.
2157 .It Fl o Ar property Ns Oo , Ns Ar property Oc Ns ...
2158 A comma-separated list of properties to display. The property must be:
2159 .Bl -bullet -offset 2n
2161 One of the properties described in the
2162 .Qq Sx Native Properties
2169 to display the dataset name
2173 to display space usage properties on file systems and volumes. This is a
2174 shortcut for specifying
2176 .Sy name,avail,used,usedsnap,usedds,usedrefreserv,usedchild
2178 .Sy filesystem,volume
2181 .It Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
2182 A comma-separated list of types to display, where
2185 .Sy filesystem , snapshot , snap , volume , bookmark , No or Sy all .
2186 For example, specifying
2188 displays only snapshots.
2189 .It Fl s Ar property
2190 A property for sorting the output by column in ascending order based on the
2191 value of the property. The property must be one of the properties described in
2194 section, or the special value
2196 to sort by the dataset name. Multiple properties can be specified at one time
2199 property options. Multiple
2201 options are evaluated from left to right in decreasing order of importance.
2203 The following is a list of sorting criteria:
2204 .Bl -bullet -offset 2n
2206 Numeric types sort in numeric order.
2208 String types sort in alphabetical order.
2210 Types inappropriate for a row sort that row to the literal bottom, regardless
2211 of the specified ordering.
2213 If no sorting options are specified the existing behavior of
2217 .It Fl S Ar property
2220 option, but sorts by property in descending order.
2225 .Ar property Ns = Ns Ar value Oo Ar property Ns = Ns Ar value Oc Ns ...
2226 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2229 Sets the property or list of properties to the given value(s) for each dataset.
2230 Only some properties can be edited. See the "Properties" section for more
2231 information on what properties can be set and acceptable values. Numeric values
2232 can be specified as exact values, or in a human-readable form with a suffix of
2233 .Sy B , K , M , G , T , P , E , Z
2234 (for bytes, kilobytes, megabytes, gigabytes, terabytes, petabytes, exabytes, or
2235 zettabytes, respectively). User properties can be set on snapshots. For more
2236 information, see the
2237 .Qq Sx User Properties
2242 .Op Fl r Ns | Ns Fl d Ar depth
2244 .Op Fl o Ar all | field Ns Oo , Ns Ar field Oc Ns ...
2245 .Op Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
2246 .Op Fl s Ar source Ns Oo , Ns Ar source Oc Ns ...
2247 .Ar all | property Ns Oo , Ns Ar property Oc Ns ...
2248 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns | Ns Ar bookmark Ns ...
2251 Displays properties for the given datasets. If no datasets are specified, then
2252 the command displays properties for all datasets on the system. For each
2253 property, the following columns are displayed:
2255 .Bl -hang -width "property" -offset indent -compact
2263 Property source. Can either be local, default, temporary, inherited, received,
2268 All columns except the
2270 column are displayed by default. The columns to display can be specified
2273 option. This command takes a comma-separated list of properties as described in
2275 .Qq Sx Native Properties
2277 .Qq Sx User Properties
2282 can be used to display all properties that apply to the given dataset's type
2283 (filesystem, volume, snapshot, or bookmark).
2284 .Bl -tag -width indent
2286 Recursively display properties for any children.
2288 Recursively display any children of the dataset, limiting the recursion to
2292 will display only the dataset and its direct children.
2294 Display output in a form more easily parsed by scripts. Any headers are
2295 omitted, and fields are explicitly separated by a single tab instead of an
2296 arbitrary amount of space.
2298 Display numbers in parsable (exact) values.
2299 .It Fl o Cm all | Ar field Ns Oo , Ns Ar field Oc Ns ...
2300 A comma-separated list of columns to display. Supported values are
2301 .Sy name,property,value,received,source .
2303 .Sy name,property,value,source .
2306 specifies all columns.
2307 .It Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
2308 A comma-separated list of types to display, where
2311 .Sy filesystem , snapshot , volume , No or Sy all .
2312 For example, specifying
2314 displays only snapshots.
2315 .It Fl s Ar source Ns Oo , Ns Ar source Oc Ns ...
2316 A comma-separated list of sources to display. Those properties coming from a
2317 source other than those in this list are ignored. Each source must be one of
2319 .Sy local,default,inherited,temporary,received,none .
2320 The default value is all sources.
2327 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
2330 Clears the specified property, causing it to be inherited from an ancestor,
2331 restored to default if no ancestor has the property set, or with the
2333 option reverted to the received value if one exists.
2336 section for a listing of default values, and details on which properties can be
2338 .Bl -tag -width indent
2340 Recursively inherit the given property for all children.
2342 Revert the property to the received value if one exists; otherwise operate as
2345 option was not specified.
2350 .Ar filesystem Ns | Ns Ar volume
2353 Remap the indirect blocks in the given filesystem or volume so that they no
2354 longer reference blocks on previously removed vdevs and we can eventually
2355 shrink the size of the indirect mapping objects for the previously removed
2356 vdevs. Note that remapping all blocks might not be possible and that
2357 references from snapshots will still exist and cannot be remapped.
2364 Displays a list of file systems that are not the most recent version.
2365 .Bl -tag -width indent
2369 filesystem versions supported by the current software. The current
2371 filesystem version and all previous supported versions are displayed, along
2372 with an explanation of the features provided with each version.
2379 .Fl a | Ar filesystem
2382 Upgrades file systems to a new on-disk version. Once this is done, the file
2383 systems will no longer be accessible on systems running older versions of the
2386 streams generated from new snapshots of these file systems cannot be accessed
2387 on systems running older versions of the software.
2389 In general, the file system version is independent of the pool version. See
2391 for information on the
2392 .Nm zpool Cm upgrade
2395 In some cases, the file system version and the pool version are interrelated
2396 and the pool version must be upgraded before the file system version can be
2398 .Bl -tag -width indent
2400 Upgrade the specified file system and all descendent file systems.
2402 Upgrade to the specified
2406 flag is not specified, this command upgrades to the most recent version. This
2407 option can only be used to increase the version number, and only up to the most
2408 recent version supported by this software.
2410 Upgrade all file systems on all imported pools.
2412 Upgrade the specified file system.
2418 .Op Fl o Ar field Ns Oo , Ns Ar field Oc Ns ...
2419 .Oo Fl s Ar field Oc Ns ...
2420 .Oo Fl S Ar field Oc Ns ...
2421 .Op Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
2422 .Ar filesystem Ns | Ns Ar snapshot
2425 Displays space consumed by, and quotas on, each user in the specified
2426 filesystem or snapshot. This corresponds to the
2427 .Sy userused@ Ns Ar user
2429 .Sy userquota@ Ns Ar user
2431 .Bl -tag -width indent
2433 Print numeric ID instead of user/group name.
2435 Do not print headers, use tab-delimited output.
2437 Use exact (parsable) numeric output.
2438 .It Fl o Ar field Ns Oo , Ns Ar field Oc Ns ...
2439 Display only the specified fields from the following set:
2440 .Sy type,name,used,quota .
2441 The default is to display all fields.
2443 Sort output by this field. The
2447 flags may be specified multiple times to sort first by one field, then by
2448 another. The default is
2449 .Fl s Cm type Fl s Cm name .
2451 Sort by this field in reverse order. See
2453 .It Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
2454 Print only the specified types from the following set:
2455 .Sy all,posixuser,smbuser,posixgroup,smbgroup .
2458 .Fl t Cm posixuser,smbuser .
2460 The default can be changed to include group types.
2462 Translate SID to POSIX ID. This flag currently has no effect on
2469 .Op Fl o Ar field Ns Oo , Ns Ar field Oc Ns ...
2470 .Oo Fl s Ar field Oc Ns ...
2471 .Oo Fl S Ar field Oc Ns ...
2472 .Op Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
2473 .Ar filesystem Ns | Ns Ar snapshot
2476 Displays space consumed by, and quotas on, each group in the specified
2477 filesystem or snapshot. This subcommand is identical to
2478 .Qq Nm Cm userspace ,
2479 except that the default types to display are
2480 .Fl t Sy posixgroup,smbgroup .
2488 file systems currently mounted.
2489 .Bl -tag -width indent
2496 .Op Fl o Ar property Ns Oo , Ns Ar property Oc Ns ...
2497 .Fl a | Ar filesystem
2503 .Bl -tag -width indent
2505 Report mount progress.
2507 Perform an overlay mount. Overlay mounts are not supported on
2509 .It Fl o Ar property Ns Oo , Ns Ar property Oc Ns ...
2510 An optional, comma-separated list of mount options to use temporarily for the
2511 duration of the mount. See the
2512 .Qq Sx Temporary Mount Point Properties
2513 section for details.
2518 This command may be executed on
2522 For more information, see variable
2527 Mount the specified filesystem.
2531 .Cm unmount Ns | Ns Cm umount
2533 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
2536 Unmounts currently mounted
2539 .Bl -tag -width indent
2541 Forcefully unmount the file system, even if it is currently in use.
2543 Unmount all available
2546 .It Ar filesystem | mountpoint
2547 Unmount the specified filesystem. The command can also be given a path to a
2549 file system mount point on the system.
2554 .Fl a | Ar filesystem
2559 file systems that have the
2562 .Bl -tag -width indent
2566 file systems that have the
2569 This command may be executed on
2573 For more information, see variable
2578 Share the specified filesystem according to the
2580 property. File systems are shared when the
2587 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
2592 file systems that have the
2595 .Bl -tag -width indent
2599 file systems that have the
2602 This command may be executed on
2606 For more information, see variable
2610 .It Ar filesystem | mountpoint
2611 Unshare the specified filesystem. The command can also be given a path to a
2613 file system shared on the system.
2622 Creates a bookmark of the given snapshot.
2623 Bookmarks mark the point in time
2624 when the snapshot was created, and can be used as the incremental source for
2629 This feature must be enabled to be used.
2631 .Xr zpool-features 7
2632 for details on ZFS feature flags and the
2639 .Op Fl i Ar snapshot | Fl I Ar snapshot
2643 Creates a stream representation of the last
2645 argument (not part of
2649 which is written to standard output. The output can be redirected to
2650 a file or to a different system (for example, using
2652 By default, a full stream is generated.
2653 .Bl -tag -width indent
2654 .It Fl i Ar snapshot
2655 Generate an incremental stream from the first
2656 .Ar snapshot Pq the incremental source
2658 .Ar snapshot Pq the incremental target .
2659 The incremental source can be specified as the last component of the
2661 .Pq the Em @ No character and following
2663 it is assumed to be from the same file system as the incremental target.
2665 If the destination is a clone, the source may be the origin snapshot, which
2666 must be fully specified (for example,
2667 .Cm pool/fs@origin ,
2670 .It Fl I Ar snapshot
2671 Generate a stream package that sends all intermediary snapshots from the first
2678 .Ic -i @a fs@b; -i @b fs@c; -i @c fs@d .
2680 source may be specified as with the
2683 .It Fl R, -replicate
2684 Generate a replication stream package, which will replicate the specified
2685 filesystem, and all descendent file systems, up to the named snapshot. When
2686 received, all properties, snapshots, descendent file systems, and clones are
2693 flags are used in conjunction with the
2695 flag, an incremental replication stream is generated. The current values of
2696 properties, and current snapshot and file system names are set when the stream
2699 flag is specified when this stream is received, snapshots and file systems that
2700 do not exist on the sending side are destroyed.
2702 Generate a deduplicated stream. Blocks which would have been sent multiple
2703 times in the send stream will only be sent once. The receiving system must
2704 also support this feature to receive a deduplicated stream. This flag can
2705 be used regardless of the dataset's
2707 property, but performance will be much better if the filesystem uses a
2708 dedup-capable checksum (eg.
2710 .It Fl L, -large-block
2711 Generate a stream which may contain blocks larger than 128KB.
2713 has no effect if the
2715 pool feature is disabled, or if the
2717 property of this filesystem has never been set above 128KB.
2718 The receiving system must have the
2720 pool feature enabled as well.
2722 .Xr zpool-features 7
2723 for details on ZFS feature flags and the
2727 Generate a more compact stream by using WRITE_EMBEDDED records for blocks
2728 which are stored more compactly on disk by the
2732 This flag has no effect if the
2736 The receiving system must have the
2742 feature is active on the sending system,
2743 then the receiving system must have that feature enabled as well.
2745 .Xr zpool-features 7
2746 for details on ZFS feature flags and the
2749 .It Fl c, -compressed
2750 Generate a more compact stream by using compressed WRITE records for blocks
2751 which are compressed on disk and in memory (see the
2753 property for details).
2756 feature is active on the sending system, then the receiving system must have that
2757 feature enabled as well. If the
2759 feature is enabled on the sending system but the
2761 option is not supplied in conjunction with
2763 then the data will be decompressed before sending so it can be split
2764 into smaller block sizes.
2766 Include the dataset's properties in the stream. This flag is implicit when
2768 is specified. The receiving system must also support this feature.
2770 Do a dry-run ("No-op") send. Do not generate any actual send data. This is
2771 useful in conjunction with the
2775 flags to determine what data will be sent.
2776 In this case, the verbose output will be written to
2777 standard output (contrast with a non-dry-run, where the stream is written
2778 to standard output and the verbose output goes to standard error).
2780 Print machine-parsable verbose information about the stream package generated.
2782 Print verbose information about the stream package generated.
2783 This information includes a per-second report of how much data has been sent.
2785 Set the process title to a per-second report of how much data has been sent.
2788 The format of the stream is committed. You will be able to receive your streams
2789 on future versions of
2795 .Op Fl i Ar snapshot Ns | Ns Ar bookmark
2796 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2799 Generate a send stream, which may be of a filesystem, and may be
2800 incremental from a bookmark.
2801 If the destination is a filesystem or volume,
2802 the pool must be read-only, or the filesystem must not be mounted.
2804 stream generated from a filesystem or volume is received, the default snapshot
2807 .Bl -tag -width indent
2808 .It Fl i Ar snapshot Ns | Ns Ar bookmark
2809 Generate an incremental send stream.
2810 The incremental source must be an earlier
2811 snapshot in the destination's history.
2812 It will commonly be an earlier
2813 snapshot in the destination's filesystem, in which case it can be
2814 specified as the last component of the name
2815 .Pq the Em # No or Em @ No character and following .
2817 If the incremental target is a clone, the incremental source can
2818 be the origin snapshot, or an earlier snapshot in the origin's filesystem,
2819 or the origin's origin, etc.
2824 Do not generate any actual send data.
2825 This is useful in conjunction with the
2829 flags to determine what data will be sent.
2830 In this case, the verbose output will be written to standard output
2831 .Po contrast with a non-dry-run, where the stream is written to standard output
2832 and the verbose output goes to standard error
2835 Print verbose information about the stream package generated.
2836 This information includes a per-second report of how much data has been sent.
2837 .It Fl L, -large-block
2838 Generate a stream which may contain blocks larger than 128KB.
2840 has no effect if the
2842 pool feature is disabled, or if the
2844 property of this filesystem has never been set above 128KB.
2845 The receiving system must have the
2847 pool feature enabled as well.
2849 .Xr zpool-features 7
2850 for details on ZFS feature flags and the
2854 Print machine-parsable verbose information about the stream package generated.
2855 .It Fl c, -compressed
2856 Generate a more compact stream by using compressed WRITE records for blocks
2857 which are compressed on disk and in memory (see the
2859 property for details). If the
2861 feature is active on the sending system, then the receiving system must have
2862 that feature enabled as well. If the
2864 feature is enabled on the sending system but the
2866 option is not supplied in conjunction with
2868 then the data will be decompressed before sending so it can be split
2869 into smaller block sizes.
2871 Generate a more compact stream by using WRITE_EMBEDDED records for blocks
2872 which are stored more compactly on disk by the
2876 This flag has no effect if the
2880 The receiving system must have the
2886 feature is active on the sending system,
2887 then the receiving system must have that feature enabled as well.
2889 .Xr zpool-features 7
2890 for details on ZFS feature flags and the
2899 .Ar receive_resume_token
2901 Creates a send stream which resumes an interrupted receive. The
2902 .Ar receive_resume_token
2903 is the value of this property on the filesystem
2904 or volume that was being received into. See the documentation for
2909 .Cm receive Ns | Ns Cm recv
2911 .Op Fl o Sy origin Ns = Ns Ar snapshot
2912 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2916 .Cm receive Ns | Ns Cm recv
2919 .Op Fl o Sy origin Ns = Ns Ar snapshot
2923 Creates a snapshot whose contents are as specified in the stream provided on
2924 standard input. If a full stream is received, then a new file system is created
2925 as well. Streams are created using the
2927 subcommand, which by default creates a full stream.
2929 can be used as an alias for
2932 If an incremental stream is received, then the destination file system must
2933 already exist, and its most recent snapshot must match the incremental stream's
2936 the destination device link is destroyed and recreated, which means the
2938 cannot be accessed during the
2942 When a snapshot replication package stream that is generated by using the
2944 command is received, any snapshots that do not exist on the sending location
2945 are destroyed by using the
2946 .Qq Nm Cm destroy Fl d
2949 The name of the snapshot (and file system, if a full stream is received) that
2950 this subcommand creates depends on the argument type and the
2956 If the argument is a snapshot name, the specified
2958 is created. If the argument is a file system or volume name, a snapshot with
2959 the same name as the sent snapshot is created within the specified
2967 option is specified, the snapshot name is determined by appending the sent
2968 snapshot's name to the specified
2972 option is specified, all but the pool name of the sent snapshot path is
2973 appended (for example,
2975 appended from sent snapshot
2979 option is specified, only the tail of the sent snapshot path is appended (for
2982 appended from sent snapshot
2986 any file systems needed to replicate the path of the sent snapshot are created
2987 within the specified file system.
2988 .Bl -tag -width indent
2990 Use the full sent snapshot path without the first element (without pool name)
2991 to determine the name of the new snapshot as described in the paragraph above.
2993 Use only the last element of the sent snapshot path to determine the name of
2994 the new snapshot as described in the paragraph above.
2996 File system that is associated with the received stream is not mounted.
2998 Print verbose information about the stream and the time required to perform the
3001 Do not actually receive the stream. This can be useful in conjunction with the
3003 option to verify the name the receive operation would use.
3004 .It Fl o Sy origin Ns = Ns Ar snapshot
3005 Forces the stream to be received as a clone of the given snapshot.
3006 If the stream is a full send stream, this will create the filesystem
3007 described by the stream as a clone of the specified snapshot. Which
3008 snapshot was specified will not affect the success or failure of the
3009 receive, as long as the snapshot does exist. If the stream is an
3010 incremental send stream, all the normal verification will be performed.
3012 Force a rollback of the file system to the most recent snapshot before
3013 performing the receive operation. If receiving an incremental replication
3014 stream (for example, one generated by
3015 .Qq Nm Cm send Fl R Bro Fl i | Fl I Brc ) ,
3016 destroy snapshots and file systems that do not exist on the sending side.
3018 If the receive is interrupted, save the partially received state, rather
3019 than deleting it. Interruption may be due to premature termination of
3021 .Po e.g. due to network failure or failure of the remote system
3022 if the stream is being read over a network connection
3024 a checksum error in the stream, termination of the
3026 process, or unclean shutdown of the system.
3028 The receive can be resumed with a stream generated by
3029 .Nm zfs Cm send Fl t Ar token ,
3033 .Sy receive_resume_token
3034 property of the filesystem or volume which is received into.
3036 To use this flag, the storage pool must have the
3037 .Sy extensible_dataset
3038 feature enabled. See
3039 .Xr zpool-features 7
3040 for details on ZFS feature flags.
3044 .Cm receive Ns | Ns Cm recv
3046 .Ar filesystem Ns | Ns Ar volume
3048 Abort an interrupted
3049 .Nm zfs Cm receive Fl s ,
3050 deleting its saved partially received state.
3054 .Ar filesystem Ns | Ns Ar volume
3057 Displays permissions that have been delegated on the specified filesystem or
3058 volume. See the other forms of
3060 for more information.
3065 .Ar user Ns | Ns Ar group Ns Oo Ns , Ns Ar user Ns | Ns Ar group Oc Ns ...
3066 .Ar perm Ns | Ns Ar @setname Ns
3067 .Oo Ns , Ns Ar perm Ns | Ns Ar @setname Oc Ns ...
3068 .Ar filesystem Ns | Ns Ar volume
3074 .Fl e Ns | Ns Cm everyone
3075 .Ar perm Ns | Ns Ar @setname Ns Op Ns , Ns Ar perm Ns | Ns Ar @setname Ns
3077 .Ar filesystem Ns | Ns Ar volume
3082 administration permission for the file systems to non-privileged users.
3083 .Bl -tag -width indent
3086 .Ar user Ns | Ns Ar group Ns Oo , Ar user Ns | Ns Ar group Oc Ns ...
3088 Specifies to whom the permissions are delegated. Multiple entities can be
3089 specified as a comma-separated list. If neither of the
3091 options are specified, then the argument is interpreted preferentially as the
3094 then as a user name, and lastly as a group name. To specify
3095 a user or group named
3101 options. To specify a group with the same name as a user, use the
3104 .It Op Fl e Ns | Ns Cm everyone
3105 Specifies that the permissions be delegated to
3108 .Ar perm Ns | Ns Ar @setname Ns Oo , Ns Ar perm Ns | Ns Ar @setname Oc Ns ...
3110 The permissions to delegate. Multiple permissions
3111 may be specified as a comma-separated list. Permission names are the same as
3113 subcommand and property names. See the property list below. Property set names,
3114 which begin with an at sign
3116 may be specified. See the
3118 form below for details.
3121 .Ar filesystem Ns | Ns Ar volume
3123 Specifies where the permissions are delegated. If neither of the
3125 options are specified, or both are, then the permissions are allowed for the
3126 file system or volume, and all of its descendents. If only the
3128 option is used, then is allowed "locally" only for the specified file system.
3131 option is used, then is allowed only for the descendent file systems.
3134 Permissions are generally the ability to use a
3136 subcommand or change a
3138 property. The following permissions are available:
3139 .Bl -column -offset 4n "secondarycache" "subcommand"
3140 .It NAME Ta TYPE Ta NOTES
3141 .It allow Ta subcommand Ta Must Xo
3142 also have the permission that is being allowed
3144 .It clone Ta subcommand Ta Must Xo
3145 also have the 'create' ability and 'mount' ability in the origin file system
3147 .It create Ta subcommand Ta Must also have the 'mount' ability
3148 .It destroy Ta subcommand Ta Must also have the 'mount' ability
3149 .It diff Ta subcommand Ta Allows lookup of paths within a dataset given an
3150 object number, and the ability to create snapshots necessary to 'zfs diff'
3151 .It hold Ta subcommand Ta Allows adding a user hold to a snapshot
3152 .It mount Ta subcommand Ta Allows mount/umount of Tn ZFS No datasets
3153 .It promote Ta subcommand Ta Must Xo
3154 also have the 'mount' and 'promote' ability in the origin file system
3156 .It receive Ta subcommand Ta Must also have the 'mount' and 'create' ability
3157 .It release Ta subcommand Ta Allows Xo
3158 releasing a user hold which might destroy the snapshot
3160 .It rename Ta subcommand Ta Must Xo
3161 also have the 'mount' and 'create' ability in the new parent
3163 .It rollback Ta subcommand Ta Must also have the 'mount' ability
3164 .It send Ta subcommand
3165 .It share Ta subcommand Ta Allows Xo
3166 sharing file systems over the
3170 .It snapshot Ta subcommand Ta Must also have the 'mount' ability
3171 .It groupquota Ta other Ta Allows accessing any groupquota@... property
3172 .It groupused Ta other Ta Allows reading any groupused@... property
3173 .It userprop Ta other Ta Allows changing any user property
3174 .It userquota Ta other Ta Allows accessing any userquota@... property
3175 .It userused Ta other Ta Allows reading any userused@... property
3176 .It aclinherit Ta property
3177 .It aclmode Ta property
3178 .It atime Ta property
3179 .It canmount Ta property
3180 .It casesensitivity Ta property
3181 .It checksum Ta property
3182 .It compression Ta property
3183 .It copies Ta property
3184 .It dedup Ta property
3185 .It devices Ta property
3186 .It exec Ta property
3187 .It filesystem_limit Ta property
3188 .It logbias Ta property
3189 .It jailed Ta property
3190 .It mlslabel Ta property
3191 .It mountpoint Ta property
3192 .It nbmand Ta property
3193 .It normalization Ta property
3194 .It primarycache Ta property
3195 .It quota Ta property
3196 .It readonly Ta property
3197 .It recordsize Ta property
3198 .It refquota Ta property
3199 .It refreservation Ta property
3200 .It reservation Ta property
3201 .It secondarycache Ta property
3202 .It setuid Ta property
3203 .It sharenfs Ta property
3204 .It sharesmb Ta property
3205 .It snapdir Ta property
3206 .It snapshot_limit Ta property
3207 .It sync Ta property
3208 .It utf8only Ta property
3209 .It version Ta property
3210 .It volblocksize Ta property
3211 .It volsize Ta property
3212 .It vscan Ta property
3213 .It xattr Ta property
3219 .Ar perm Ns | Ns Ar @setname Ns Op Ns , Ns Ar perm Ns | Ns Ar @setname Ns
3221 .Ar filesystem Ns | Ns Ar volume
3224 Sets "create time" permissions. These permissions are granted (locally) to the
3225 creator of any newly-created descendent file system.
3231 .Ar perm Ns | Ns Ar @setname Ns Op Ns , Ns Ar perm Ns | Ns Ar @setname Ns
3233 .Ar filesystem Ns | Ns Ar volume
3236 Defines or adds permissions to a permission set. The set can be used by other
3238 commands for the specified file system and its descendents. Sets are evaluated
3239 dynamically, so changes to a set are immediately reflected. Permission sets
3240 follow the same naming restrictions as ZFS file systems, but the name must
3241 begin with an "at sign"
3243 and can be no more than 64 characters long.
3248 .Ar user Ns | Ns Ar group Ns Oo Ns , Ns Ar user Ns | Ns Ar group Oc Ns ...
3249 .Oo Ar perm Ns | Ns Ar @setname Ns Op , Ns Ar perm Ns | Ns Ar @setname Ns
3251 .Ar filesystem Ns | Ns Ar volume
3257 .Fl e Ns | Ns Cm everyone
3258 .Oo Ar perm Ns | Ns Ar @setname Ns Op , Ns Ar perm Ns | Ns Ar @setname Ns
3260 .Ar filesystem Ns | Ns Ar volume
3267 .Oo Ar perm Ns | Ns Ar @setname Ns Op , Ns Ar perm Ns | Ns Ar @setname Ns
3269 .Ar filesystem Ns | Ns Ar volume
3272 Removes permissions that were granted with the
3274 command. No permissions are explicitly denied, so other permissions granted are
3275 still in effect. For example, if the permission is granted by an ancestor. If
3276 no permissions are specified, then all permissions for the specified
3277 .Ar user , group , No or everyone
3278 are removed. Specifying
3280 .Po or using the Fl e
3282 .Pc only removes the permissions that were granted to everyone ,
3283 not all permissions for every user and group. See the
3285 command for a description of the
3288 .Bl -tag -width indent
3290 Recursively remove the permissions from this file system and all descendents.
3298 .Oo Ar perm Ns | Ns Ar @setname Ns Op , Ns Ar perm Ns | Ns Ar @setname Ns
3300 .Ar filesystem Ns | Ns Ar volume
3303 Removes permissions from a permission set. If no permissions are specified,
3304 then all permissions are removed, thus removing the set entirely.
3309 .Ar tag snapshot Ns ...
3312 Adds a single reference, named with the
3314 argument, to the specified snapshot or snapshots. Each snapshot has its own tag
3315 namespace, and tags must be unique within that space.
3317 If a hold exists on a snapshot, attempts to destroy that snapshot by using the
3321 .Bl -tag -width indent
3323 Specifies that a hold with the given tag is applied recursively to the
3324 snapshots of all descendent file systems.
3330 .Op Fl r Ns | Ns Fl d Ar depth
3331 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns
3335 Lists all existing user references for the given dataset or datasets.
3336 .Bl -tag -width indent
3338 Used for scripting mode. Do not print headers and separate fields by a single
3339 tab instead of arbitrary white space.
3341 Display numbers in parsable (exact) values.
3343 Lists the holds that are set on the descendent snapshots of the named datasets
3344 or snapshots, in addition to listing the holds on the named snapshots, if any.
3346 Recursively display any holds on the named snapshots, or descendent snapshots of
3347 the named datasets or snapshots, limiting the recursion to
3354 .Ar tag snapshot Ns ...
3357 Removes a single reference, named with the
3359 argument, from the specified snapshot or snapshots. The tag must already exist
3361 .Bl -tag -width indent
3363 Recursively releases a hold with the given tag on the snapshots of all
3364 descendent file systems.
3371 .Op Ar snapshot Ns | Ns Ar filesystem
3374 Display the difference between a snapshot of a given filesystem and another
3375 snapshot of that filesystem from a later time or the current contents of the
3376 filesystem. The first column is a character indicating the type of change,
3377 the other columns indicate pathname, new pathname
3378 .Pq in case of rename ,
3379 change in link count, and optionally file type and/or change time.
3381 The types of change are:
3382 .Bl -column -offset 2n indent
3383 .It \&- Ta path was removed
3384 .It \&+ Ta path was added
3385 .It \&M Ta path was modified
3386 .It \&R Ta path was renamed
3388 .Bl -tag -width indent
3390 Display an indication of the type of file, in a manner similar to the
3394 .Bl -column -offset 2n indent
3395 .It \&B Ta block device
3396 .It \&C Ta character device
3397 .It \&F Ta regular file
3398 .It \&/ Ta directory
3399 .It \&@ Ta symbolic link
3401 .It \&> Ta door (not supported on Fx )
3402 .It \&| Ta named pipe (not supported on Fx )
3403 .It \&P Ta event port (not supported on Fx )
3406 Give more parsable tab-separated output, without header lines and without
3409 Display the path's inode change time as the first column of output.
3416 .Op Fl m Ar memory_limit
3423 as a ZFS channel program on
3426 program interface allows ZFS administrative operations to be run
3427 programmatically via a Lua script.
3428 The entire script is executed atomically, with no other administrative
3429 operations taking effect concurrently.
3430 A library of ZFS calls is made available to channel program scripts.
3431 Channel programs may only be run with root privileges.
3433 For full documentation of the ZFS channel program interface, see the manual
3436 .Bl -tag -width indent
3438 Display channel program output in JSON format.
3439 When this flag is specified and standard output is empty -
3440 channel program encountered an error.
3441 The details of such an error will be printed to standard error in plain text.
3443 Executes a read-only channel program, which runs faster.
3444 The program cannot change on-disk state by calling functions from
3445 the zfs.sync submodule.
3446 The program can be used to gather information such as properties and
3447 determining if changes would succeed (zfs.check.*).
3448 Without this flag, all pending changes must be synced to disk before
3449 a channel program can complete.
3451 Execution time limit, in milliseconds.
3452 If a channel program executes for longer than the provided timeout, it will
3453 be stopped and an error will be returned.
3454 The default timeout is 1000 ms, and can be set to a maximum of 10000 ms.
3455 .It Fl m Ar memory-limit
3456 Memory limit, in bytes.
3457 If a channel program attempts to allocate more memory than the given limit,
3458 it will be stopped and an error returned.
3459 The default memory limit is 10 MB, and can be set to a maximum of 100 MB.
3461 All remaining argument strings are passed directly to the channel program as
3465 for more information.
3470 .Ar jailid filesystem
3473 Attaches the specified
3475 to the jail identified by JID
3477 From now on this file system tree can be managed from within a jail if the
3479 property has been set. To use this functionality, the jail needs the
3483 parameters set to 1 and the
3485 parameter set to a value lower than 2.
3489 for more information on managing jails and configuring the parameters above.
3493 .Ar jailid filesystem
3496 Detaches the specified
3498 from the jail identified by JID
3502 The following exit values are returned:
3503 .Bl -tag -offset 2n -width 2n
3505 Successful completion.
3509 Invalid command line options were specified.
3513 .It Sy Example 1 No Creating a Tn ZFS No File System Hierarchy
3515 The following commands create a file system named
3517 and a file system named
3521 is set for the parent file system, and is automatically inherited by the child
3523 .Bd -literal -offset 2n
3524 .Li # Ic zfs create pool/home
3525 .Li # Ic zfs set mountpoint=/home pool/home
3526 .Li # Ic zfs create pool/home/bob
3528 .It Sy Example 2 No Creating a Tn ZFS No Snapshot
3530 The following command creates a snapshot named
3532 This snapshot is mounted on demand in the
3534 directory at the root of the
3537 .Bd -literal -offset 2n
3538 .Li # Ic zfs snapshot pool/home/bob@yesterday
3540 .It Sy Example 3 No Creating and Destroying Multiple Snapshots
3542 The following command creates snapshots named
3546 and all of its descendent file systems. Each snapshot is mounted on demand in
3549 directory at the root of its file system. The second command destroys the newly
3551 .Bd -literal -offset 2n
3552 .Li # Ic zfs snapshot -r pool/home@yesterday
3553 .Li # Ic zfs destroy -r pool/home@yesterday
3555 .It Sy Example 4 No Disabling and Enabling File System Compression
3557 The following command disables the
3559 property for all file systems under
3561 The next command explicitly enables
3564 .Em pool/home/anne .
3565 .Bd -literal -offset 2n
3566 .Li # Ic zfs set compression=off pool/home
3567 .Li # Ic zfs set compression=on pool/home/anne
3569 .It Sy Example 5 No Listing Tn ZFS No Datasets
3571 The following command lists all active file systems and volumes in the system.
3572 Snapshots are displayed if the
3580 for more information on pool properties.
3581 .Bd -literal -offset 2n
3583 NAME USED AVAIL REFER MOUNTPOINT
3584 pool 450K 457G 18K /pool
3585 pool/home 315K 457G 21K /home
3586 pool/home/anne 18K 457G 18K /home/anne
3587 pool/home/bob 276K 457G 276K /home/bob
3589 .It Sy Example 6 No Setting a Quota on a Tn ZFS No File System
3591 The following command sets a quota of 50 Gbytes for
3593 .Bd -literal -offset 2n
3594 .Li # Ic zfs set quota=50G pool/home/bob
3596 .It Sy Example 7 No Listing Tn ZFS No Properties
3598 The following command lists all properties for
3600 .Bd -literal -offset 2n
3601 .Li # Ic zfs get all pool/home/bob
3602 NAME PROPERTY VALUE SOURCE
3603 pool/home/bob type filesystem -
3604 pool/home/bob creation Tue Jul 21 15:53 2009 -
3605 pool/home/bob used 21K -
3606 pool/home/bob available 20.0G -
3607 pool/home/bob referenced 21K -
3608 pool/home/bob compressratio 1.00x -
3609 pool/home/bob mounted yes -
3610 pool/home/bob quota 20G local
3611 pool/home/bob reservation none default
3612 pool/home/bob recordsize 128K default
3613 pool/home/bob mountpoint /home/bob default
3614 pool/home/bob sharenfs off default
3615 pool/home/bob checksum on default
3616 pool/home/bob compression on local
3617 pool/home/bob atime on default
3618 pool/home/bob devices on default
3619 pool/home/bob exec on default
3620 pool/home/bob filesystem_limit none default
3621 pool/home/bob setuid on default
3622 pool/home/bob readonly off default
3623 pool/home/bob jailed off default
3624 pool/home/bob snapdir hidden default
3625 pool/home/bob snapshot_limit none default
3626 pool/home/bob aclmode discard default
3627 pool/home/bob aclinherit restricted default
3628 pool/home/bob canmount on default
3629 pool/home/bob xattr on default
3630 pool/home/bob copies 1 default
3631 pool/home/bob version 5 -
3632 pool/home/bob utf8only off -
3633 pool/home/bob normalization none -
3634 pool/home/bob casesensitivity sensitive -
3635 pool/home/bob vscan off default
3636 pool/home/bob nbmand off default
3637 pool/home/bob sharesmb off default
3638 pool/home/bob refquota none default
3639 pool/home/bob refreservation none default
3640 pool/home/bob primarycache all default
3641 pool/home/bob secondarycache all default
3642 pool/home/bob usedbysnapshots 0 -
3643 pool/home/bob usedbydataset 21K -
3644 pool/home/bob usedbychildren 0 -
3645 pool/home/bob usedbyrefreservation 0 -
3646 pool/home/bob logbias latency default
3647 pool/home/bob dedup off default
3648 pool/home/bob mlslabel -
3649 pool/home/bob sync standard default
3650 pool/home/bob refcompressratio 1.00x -
3653 The following command gets a single property value.
3654 .Bd -literal -offset 2n
3655 .Li # Ic zfs get -H -o value compression pool/home/bob
3659 The following command lists all properties with local settings for
3661 .Bd -literal -offset 2n
3662 .Li # Ic zfs get -s local -o name,property,value all pool/home/bob
3664 pool/home/bob quota 20G
3665 pool/home/bob compression on
3667 .It Sy Example 8 No Rolling Back a Tn ZFS No File System
3669 The following command reverts the contents of
3671 to the snapshot named
3673 deleting all intermediate snapshots.
3674 .Bd -literal -offset 2n
3675 .Li # Ic zfs rollback -r pool/home/anne@yesterday
3677 .It Sy Example 9 No Creating a Tn ZFS No Clone
3679 The following command creates a writable file system whose initial contents are
3681 .Em pool/home/bob@yesterday .
3682 .Bd -literal -offset 2n
3683 .Li # Ic zfs clone pool/home/bob@yesterday pool/clone
3685 .It Sy Example 10 No Promoting a Tn ZFS No Clone
3687 The following commands illustrate how to test out changes to a file system, and
3688 then replace the original file system with the changed one, using clones, clone
3689 promotion, and renaming:
3690 .Bd -literal -offset 2n
3691 .Li # Ic zfs create pool/project/production
3695 .Pa /pool/project/production
3696 with data and continue with the following commands:
3697 .Bd -literal -offset 2n
3698 .Li # Ic zfs snapshot pool/project/production@today
3699 .Li # Ic zfs clone pool/project/production@today pool/project/beta
3703 .Pa /pool/project/beta
3704 and continue with the following commands:
3705 .Bd -literal -offset 2n
3706 .Li # Ic zfs promote pool/project/beta
3707 .Li # Ic zfs rename pool/project/production pool/project/legacy
3708 .Li # Ic zfs rename pool/project/beta pool/project/production
3711 Once the legacy version is no longer needed, it can be destroyed.
3712 .Bd -literal -offset 2n
3713 .Li # Ic zfs destroy pool/project/legacy
3715 .It Sy Example 11 No Inheriting Tn ZFS No Properties
3717 The following command causes
3723 property from their parent.
3724 .Bd -literal -offset 2n
3725 .Li # Ic zfs inherit checksum pool/home/bob pool/home/anne
3727 .It Sy Example 12 No Remotely Replicating Tn ZFS No Data
3729 The following commands send a full stream and then an incremental stream to a
3730 remote machine, restoring them into
3731 .Sy poolB/received/fs@a
3733 .Sy poolB/received/fs@b ,
3736 must contain the file system
3737 .Sy poolB/received ,
3738 and must not initially contain
3739 .Sy poolB/received/fs .
3740 .Bd -literal -offset 2n
3741 .Li # Ic zfs send pool/fs@a | ssh host zfs receive poolB/received/fs@a
3742 .Li # Ic zfs send -i a pool/fs@b | ssh host zfs receive poolB/received/fs
3751 The following command sends a full stream of
3752 .Sy poolA/fsA/fsB@snap
3753 to a remote machine, receiving it into
3754 .Sy poolB/received/fsA/fsB@snap .
3757 portion of the received snapshot's name is determined from the name of the sent
3760 must contain the file system
3761 .Sy poolB/received .
3763 .Sy poolB/received/fsA
3764 does not exist, it is created as an empty file system.
3765 .Bd -literal -offset 2n
3766 .Li # Ic zfs send poolA/fsA/fsB@snap | ssh host zfs receive -d poolB/received
3768 .It Sy Example 14 No Setting User Properties
3770 The following example sets the user-defined
3771 .Sy com.example:department
3772 property for a dataset.
3773 .Bd -literal -offset 2n
3774 .Li # Ic zfs set com.example:department=12345 tank/accounting
3776 .It Sy Example 15 No Performing a Rolling Snapshot
3778 The following example shows how to maintain a history of snapshots with a
3779 consistent naming scheme. To keep a week's worth of snapshots, the user
3780 destroys the oldest snapshot, renames the remaining snapshots, and then creates
3781 a new snapshot, as follows:
3782 .Bd -literal -offset 2n
3783 .Li # Ic zfs destroy -r pool/users@7daysago
3784 .Li # Ic zfs rename -r pool/users@6daysago @7daysago
3785 .Li # Ic zfs rename -r pool/users@5daysago @6daysago
3786 .Li # Ic zfs rename -r pool/users@4daysago @5daysago
3787 .Li # Ic zfs rename -r pool/users@3daysago @4daysago
3788 .Li # Ic zfs rename -r pool/users@2daysago @3daysago
3789 .Li # Ic zfs rename -r pool/users@yesterday @2daysago
3790 .Li # Ic zfs rename -r pool/users@today @yesterday
3791 .Li # Ic zfs snapshot -r pool/users@today
3797 Property Options on a ZFS File System
3800 The following command shows how to set
3802 property options to enable root access for a specific network on the
3804 file system. The contents of the
3809 .Bd -literal -offset 2n
3810 .Li # Ic zfs set sharenfs="maproot=root,network 192.168.0.0/24" tank/home
3813 Another way to write this command with the same result is:
3814 .Bd -literal -offset 2n
3815 .Li # Ic set zfs sharenfs="-maproot=root -network 192.168.0.0/24" tank/home
3821 Administration Permissions on a
3826 The following example shows how to set permissions so that user
3828 can create, destroy, mount, and take snapshots on
3833 .Bd -literal -offset 2n
3834 .Li # Ic zfs allow cindys create,destroy,mount,snapshot tank/cindys
3835 .Li # Ic zfs allow tank/cindys
3836 ---- Permissions on tank/cindys --------------------------------------
3837 Local+Descendent permissions:
3838 user cindys create,destroy,mount,snapshot
3840 .It Sy Example 18 No Delegating Create Time Permissions on a Tn ZFS No Dataset
3842 The following example shows how to grant anyone in the group
3844 to create file systems in
3846 This syntax also allows staff members to destroy their own file systems, but
3847 not destroy anyone else's file system. The permissions on
3850 .Bd -literal -offset 2n
3851 .Li # Ic zfs allow staff create,mount tank/users
3852 .Li # Ic zfs allow -c destroy tank/users
3853 .Li # Ic zfs allow tank/users
3854 ---- Permissions on tank/users ---------------------------------------
3857 Local+Descendent permissions:
3858 group staff create,mount
3862 Defining and Granting a Permission Set on a
3867 The following example shows how to define and grant a permission set on the
3869 file system. The permissions on
3872 .Bd -literal -offset 2n
3873 .Li # Ic zfs allow -s @pset create,destroy,snapshot,mount tank/users
3874 .Li # Ic zfs allow staff @pset tank/users
3875 .Li # Ic zfs allow tank/users
3876 ---- Permissions on tank/users ---------------------------------------
3878 @pset create,destroy,mount,snapshot
3879 Local+Descendent permissions:
3882 .It Sy Example 20 No Delegating Property Permissions on a Tn ZFS No Dataset
3884 The following example shows to grant the ability to set quotas and reservations
3887 file system. The permissions on
3890 .Bd -literal -offset 2n
3891 .Li # Ic zfs allow cindys quota,reservation users/home
3892 .Li # Ic zfs allow users/home
3893 ---- Permissions on users/home ---------------------------------------
3894 Local+Descendent permissions:
3895 user cindys quota,reservation
3896 .Li # Ic su - cindys
3897 .Li cindys% Ic zfs set quota=10G users/home/marks
3898 .Li cindys% Ic zfs get quota users/home/marks
3899 NAME PROPERTY VALUE SOURCE
3900 users/home/marks quota 10G local
3902 .It Sy Example 21 No Removing ZFS Delegated Permissions on a Tn ZFS No Dataset
3904 The following example shows how to remove the snapshot permission from the
3908 file system. The permissions on
3911 .Bd -literal -offset 2n
3912 .Li # Ic zfs unallow staff snapshot tank/users
3913 .Li # Ic zfs allow tank/users
3914 ---- Permissions on tank/users ---------------------------------------
3916 @pset create,destroy,mount,snapshot
3917 Local+Descendent permissions:
3920 .It Sy Example 22 Showing the differences between a snapshot and a ZFS Dataset
3922 The following example shows how to see what has changed between a prior
3923 snapshot of a ZFS Dataset and its current state. The
3925 option is used to indicate type information for the files affected.
3926 .Bd -literal -offset 2n
3927 .Li # Ic zfs diff tank/test@before tank/test
3929 M F /tank/test/linked (+1)
3930 R F /tank/test/oldname -> /tank/test/newname
3931 - F /tank/test/deleted
3932 + F /tank/test/created
3933 M F /tank/test/modified
3948 This manual page is a
3950 reimplementation of the
3954 modified and customized for
3956 and licensed under the
3957 Common Development and Distribution License
3962 implementation of this manual page was initially written by
3963 .An Martin Matuska Aq mm@FreeBSD.org .
projects / FreeBSD / FreeBSD.git / blob