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38 .Nd configures ZFS file systems
45 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
51 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
52 .Fl V Ar size Ar volume
56 .Ar filesystem Ns | Ns Ar volume
60 .Ar filesystem Ns | Ns Ar volume Ns @ Ns Ar snap Ns
61 .Oo % Ns Ar snap Ns Oo , Ns Ar snap Ns Oo % Ns Ar snap Oc Oc Oc Ns ...
64 .Ar filesystem Ns | Ns Ar volume Ns # Ns Ar bookmark
68 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
69 .Ar filesystem Ns @ Ns Ar snapname Ns | Ns Ar volume Ns @ Ns Ar snapname Ns ...
77 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
78 .Ar snapshot Ar filesystem Ns | Ns Ar volume
85 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
86 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
90 .Ar filesystem Ns | Ns Ar volume
91 .Ar filesystem Ns | Ns Ar volume
95 .Ar snapshot Ar snapshot
98 .Op Fl r Ns | Ns Fl d Ar depth
100 .Oo Fl o Ar property Ns Oo , Ns Ar property Oc Ns ... Oc
101 .Oo Fl s Ar property Oc Ns ...
102 .Oo Fl S Ar property Oc Ns ...
103 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
104 .Oo Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Oc Ns ...
107 .Ar filesystem Ns | Ns Ar volume
110 .Ar property Ns = Ns Ar value Oo Ar property Ns = Ns Ar value Oc Ns ...
111 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
114 .Op Fl r Ns | Ns Fl d Ar depth
116 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
117 .Oo Fl s Ar source Ns Oo , Ns Ar source Oc Ns ... Oc
118 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
119 .Cm all | Ar property Ns Oo , Ns Ar property Oc Ns ...
120 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns | Ns Ar bookmark Ns ...
124 .Ar property Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
134 .Fl a | Ar filesystem
138 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
139 .Oo Fl s Ar field Oc Ns ...
140 .Oo Fl S Ar field Oc Ns ...
141 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
142 .Ar filesystem Ns | Ns Ar snapshot
146 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
147 .Oo Fl s Ar field Oc Ns ...
148 .Oo Fl S Ar field Oc Ns ...
149 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
150 .Ar filesystem Ns | Ns Ar snapshot
154 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
155 .Oo Fl s Ar field Oc Ns ...
156 .Oo Fl S Ar field Oc Ns ...
157 .Ar filesystem Ns | Ns Ar snapshot
160 .Oo Fl d Ns | Ns Fl r Ns Oc
161 .Ar file Ns | Ns Ar directory Ns ...
166 .Ar file Ns | Ns Ar directory Ns ...
171 .Oo Fl d Ns | Ns Fl r Ns Oc
173 .Ar file Ns | Ns Ar directory Ns ...
178 .Ar file Ns | Ns Ar directory Ns ...
185 .Fl a | Ar filesystem
189 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
192 .Fl a | Ar filesystem
195 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
198 .Ar snapshot bookmark
202 .Op Oo Fl I Ns | Ns Fl i Oc Ar snapshot
207 .Op Fl i Ar snapshot Ns | Ns Ar bookmark
208 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
212 .Fl t Ar receive_resume_token
216 .Op Fl o Sy origin Ns = Ns Ar snapshot
217 .Op Fl o Ar property Ns = Ns Ar value
219 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
223 .Op Fl d Ns | Ns Fl e
224 .Op Fl o Sy origin Ns = Ns Ar snapshot
225 .Op Fl o Ar property Ns = Ns Ar value
231 .Ar filesystem Ns | Ns Ar volume
234 .Ar filesystem Ns | Ns Ar volume
238 .Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
239 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
240 .Ar setname Oc Ns ...
241 .Ar filesystem Ns | Ns Ar volume
245 .Fl e Ns | Ns Sy everyone
246 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
247 .Ar setname Oc Ns ...
248 .Ar filesystem Ns | Ns Ar volume
252 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
253 .Ar setname Oc Ns ...
254 .Ar filesystem Ns | Ns Ar volume
257 .Fl s No @ Ns Ar setname
258 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
259 .Ar setname Oc Ns ...
260 .Ar filesystem Ns | Ns Ar volume
264 .Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
265 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
266 .Ar setname Oc Ns ... Oc
267 .Ar filesystem Ns | Ns Ar volume
271 .Fl e Ns | Ns Sy everyone
272 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
273 .Ar setname Oc Ns ... Oc
274 .Ar filesystem Ns | Ns Ar volume
279 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
280 .Ar setname Oc Ns ... Oc
281 .Ar filesystem Ns | Ns Ar volume
285 .Fl s @ Ns Ar setname
286 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
287 .Ar setname Oc Ns ... Oc
288 .Ar filesystem Ns | Ns Ar volume
292 .Ar tag Ar snapshot Ns ...
300 .Ar tag Ar snapshot Ns ...
304 .Ar snapshot Ar snapshot Ns | Ns Ar filesystem
309 .Op Fl m Ar memory_limit
315 .Op Fl L Ar keylocation
316 .Fl a | Ar filesystem
320 .Fl a | Ar filesystem
324 .Op Fl o Ar keylocation Ns = Ns Ar value
325 .Op Fl o Ar keyformat Ns = Ns Ar value
326 .Op Fl o Ar pbkdf2iters Ns = Ns Ar value
336 command configures ZFS datasets within a ZFS storage pool, as described in
338 A dataset is identified by a unique path within the ZFS namespace.
341 pool/{filesystem,volume,snapshot}
344 where the maximum length of a dataset name is
348 A dataset can be one of the following:
349 .Bl -tag -width "file system"
351 A ZFS dataset of type
353 can be mounted within the standard system namespace and behaves like other file
355 While ZFS file systems are designed to be POSIX compliant, known issues exist
356 that prevent compliance in some cases.
357 Applications that depend on standards conformance might fail due to non-standard
358 behavior when checking file system free space.
360 A logical volume exported as a raw or block device.
361 This type of dataset should only be used under special circumstances.
362 File systems are typically used in most environments.
364 A read-only version of a file system or volume at a given point in time.
366 .Ar filesystem Ns @ Ns Ar name
368 .Ar volume Ns @ Ns Ar name .
372 but without the hold on on-disk data. It can be used as the source of a send
373 (but not for a receive). It is specified as
374 .Ar filesystem Ns # Ns Ar name
376 .Ar volume Ns # Ns Ar name .
378 .Ss ZFS File System Hierarchy
379 A ZFS storage pool is a logical collection of devices that provide space for
381 A storage pool is also the root of the ZFS file system hierarchy.
383 The root of the pool can be accessed as a file system, such as mounting and
384 unmounting, taking snapshots, and setting properties.
385 The physical storage characteristics, however, are managed by the
391 for more information on creating and administering pools.
393 A snapshot is a read-only copy of a file system or volume.
394 Snapshots can be created extremely quickly, and initially consume no additional
395 space within the pool.
396 As data within the active dataset changes, the snapshot consumes more data than
397 would otherwise be shared with the active dataset.
399 Snapshots can have arbitrary names.
400 Snapshots of volumes can be cloned or rolled back, visibility is determined
403 property of the parent volume.
405 File system snapshots can be accessed under the
407 directory in the root of the file system.
408 Snapshots are automatically mounted on demand and may be unmounted at regular
410 The visibility of the
412 directory can be controlled by the
416 A bookmark is like a snapshot, a read-only copy of a file system or volume.
417 Bookmarks can be created extremely quickly, compared to snapshots, and they
418 consume no additional space within the pool. Bookmarks can also have arbitrary
419 names, much like snapshots.
421 Unlike snapshots, bookmarks can not be accessed through the filesystem in any
422 way. From a storage standpoint a bookmark just provides a way to reference
423 when a snapshot was created as a distinct object. Bookmarks are initially
424 tied to a snapshot, not the filesystem or volume, and they will survive if the
425 snapshot itself is destroyed. Since they are very light weight there's little
426 incentive to destroy them.
428 A clone is a writable volume or file system whose initial contents are the same
430 As with snapshots, creating a clone is nearly instantaneous, and initially
431 consumes no additional space.
433 Clones can only be created from a snapshot.
434 When a snapshot is cloned, it creates an implicit dependency between the parent
436 Even though the clone is created somewhere else in the dataset hierarchy, the
437 original snapshot cannot be destroyed as long as a clone exists.
440 property exposes this dependency, and the
442 command lists any such dependencies, if they exist.
444 The clone parent-child dependency relationship can be reversed by using the
449 file system to become a clone of the specified file system, which makes it
450 possible to destroy the file system that the clone was created from.
452 Creating a ZFS file system is a simple operation, so the number of file systems
453 per system is likely to be numerous.
454 To cope with this, ZFS automatically manages mounting and unmounting file
455 systems without the need to edit the
458 All automatically managed file systems are mounted by ZFS at boot time.
460 By default, file systems are mounted under
464 is the name of the file system in the ZFS namespace.
465 Directories are created and destroyed as needed.
467 A file system can also have a mount point set in the
470 This directory is created as needed, and ZFS automatically mounts the file
472 .Nm zfs Cm mount Fl a
479 property can be inherited, so if
485 automatically inherits a mount point of
486 .Pa /export/stuff/user .
492 prevents the file system from being mounted.
494 If needed, ZFS file systems can also be managed with traditional tools
500 If a file system's mount point is set to
502 ZFS makes no attempt to manage the file system, and the administrator is
503 responsible for mounting and unmounting the file system. Because pools must
504 be imported before a legacy mount can succeed, administrators should ensure
505 that legacy mounts are only attempted after the zpool import process
506 finishes at boot time. For example, on machines using systemd, the mount
509 .Nm x-systemd.requires=zfs-import.target
511 will ensure that the zfs-import completes before systemd attempts mounting
512 the filesystem. See systemd.mount(5) for details.
514 Deduplication is the process for removing redundant data at the block level,
515 reducing the total amount of data stored. If a file system has the
517 property enabled, duplicate data blocks are removed synchronously. The result
518 is that only unique data is stored and common components are shared among files.
520 Deduplicating data is a very resource-intensive operation. It is generally
521 recommended that you have at least 1.25 GiB of RAM per 1 TiB of storage when
522 you enable deduplication. Calculating the exact requirement depends heavily
523 on the type of data stored in the pool.
525 Enabling deduplication on an improperly-designed system can result in
526 performance issues (slow IO and administrative operations). It can potentially
527 lead to problems importing a pool due to memory exhaustion. Deduplication
528 can consume significant processing power (CPU) and memory as well as generate
531 Before creating a pool with deduplication enabled, ensure that you have planned
532 your hardware requirements appropriately and implemented appropriate recovery
533 practices, such as regular backups. As an alternative to deduplication
536 as a less resource-intensive alternative.
537 .Ss Native Properties
538 Properties are divided into two types, native properties and user-defined
543 Native properties either export internal statistics or control ZFS behavior.
544 In addition, native properties are either editable or read-only.
545 User properties have no effect on ZFS behavior, but you can use them to annotate
546 datasets in a way that is meaningful in your environment.
547 For more information about user properties, see the
551 Every dataset has a set of properties that export statistics about the dataset
552 as well as control various behaviors.
553 Properties are inherited from the parent unless overridden by the child.
554 Some properties apply only to certain types of datasets
555 .Pq file systems, volumes, or snapshots .
557 The values of numeric properties can be specified using human-readable suffixes
567 The following are all valid
570 .Li 1536M, 1.5g, 1.50GB .
572 The values of non-numeric properties are case sensitive and must be lowercase,
579 The following native properties consist of read-only statistics about the
581 These properties can be neither set, nor inherited.
582 Native properties apply to all dataset types unless otherwise noted.
583 .Bl -tag -width "usedbyrefreservation"
585 The amount of space available to the dataset and all its children, assuming that
586 there is no other activity in the pool.
587 Because space is shared within a pool, availability can be limited by any number
588 of factors, including physical pool size, quotas, reservations, or other
589 datasets within the pool.
591 This property can also be referred to by its shortened column name,
594 For non-snapshots, the compression ratio achieved for the
596 space of this dataset, expressed as a multiplier.
599 property includes descendant datasets, and, for clones, does not include the
600 space shared with the origin snapshot.
606 Compression can be turned on by running:
607 .Nm zfs Cm set Sy compression Ns = Ns Sy on Ar dataset .
611 The transaction group (txg) in which the dataset was created. Bookmarks have
614 as the snapshot they are initially tied to. This property is suitable for
615 ordering a list of snapshots, e.g. for incremental send and receive.
617 The time this dataset was created.
619 For snapshots, this property is a comma-separated list of filesystems or volumes
620 which are clones of this snapshot.
623 property is this snapshot.
626 property is not empty, then this snapshot can not be destroyed
633 The roles of origin and clone can be swapped by promoting the clone with the
639 if the snapshot has been marked for deferred destroy by using the
640 .Nm zfs Cm destroy Fl d
642 Otherwise, the property is
644 .It Sy encryptionroot
645 For encrypted datasets, indicates where the dataset is currently inheriting its
646 encryption key from. Loading or unloading a key for the
648 will implicitly load / unload the key for any inheriting datasets (see
651 .Nm zfs Cm unload-key
653 Clones will always share an
654 encryption key with their origin. See the
657 .It Sy filesystem_count
658 The total number of filesystems and volumes that exist under this location in
660 This value is only available when a
662 has been set somewhere in the tree under which the dataset resides.
664 Indicates if an encryption key is currently loaded into ZFS. The possible
673 .Nm zfs Cm unload-key .
675 The 64 bit GUID of this dataset or bookmark which does not change over its
676 entire lifetime. When a snapshot is sent to another pool, the received
677 snapshot has the same GUID. Thus, the
679 is suitable to identify a snapshot across pools.
680 .It Sy logicalreferenced
681 The amount of space that is
683 accessible by this dataset.
687 The logical space ignores the effect of the
691 properties, giving a quantity closer to the amount of data that applications
693 However, it does include space consumed by metadata.
695 This property can also be referred to by its shortened column name,
698 The amount of space that is
700 consumed by this dataset and all its descendents.
704 The logical space ignores the effect of the
708 properties, giving a quantity closer to the amount of data that applications
710 However, it does include space consumed by metadata.
712 This property can also be referred to by its shortened column name,
715 For file systems, indicates whether the file system is currently mounted.
716 This property can be either
721 For cloned file systems or volumes, the snapshot from which the clone was
726 .It Sy receive_resume_token
727 For filesystems or volumes which have saved partially-completed state from
729 this opaque token can be provided to
731 to resume and complete the
734 The amount of data that is accessible by this dataset, which may or may not be
735 shared with other datasets in the pool.
736 When a snapshot or clone is created, it initially references the same amount of
737 space as the file system or snapshot it was created from, since its contents are
740 This property can also be referred to by its shortened column name,
742 .It Sy refcompressratio
743 The compression ratio achieved for the
745 space of this dataset, expressed as a multiplier.
749 .It Sy snapshot_count
750 The total number of snapshots that exist under this location in the dataset
752 This value is only available when a
754 has been set somewhere in the tree under which the dataset resides.
762 The amount of space consumed by this dataset and all its descendents.
763 This is the value that is checked against this dataset's quota and reservation.
764 The space used does not include this dataset's reservation, but does take into
765 account the reservations of any descendent datasets.
766 The amount of space that a dataset consumes from its parent, as well as the
767 amount of space that is freed if this dataset is recursively destroyed, is the
768 greater of its space used and its reservation.
770 The used space of a snapshot
775 is space that is referenced exclusively by this snapshot.
776 If this snapshot is destroyed, the amount of
779 Space that is shared by multiple snapshots isn't accounted for in this metric.
780 When a snapshot is destroyed, space that was previously shared with this
781 snapshot can become unique to snapshots adjacent to it, thus changing the used
782 space of those snapshots.
783 The used space of the latest snapshot can also be affected by changes in the
787 space of a snapshot is a subset of the
789 space of the snapshot.
791 The amount of space used, available, or referenced does not take into account
793 Pending changes are generally accounted for within a few seconds.
794 Committing a change to a disk using
798 does not necessarily guarantee that the space usage information is updated
803 properties decompose the
805 properties into the various reasons that space is used.
808 .Sy usedbychildren No +
809 .Sy usedbydataset No +
810 .Sy usedbyrefreservation No +
811 .Sy usedbysnapshots .
812 These properties are only available for datasets created on
816 .It Sy usedbychildren
817 The amount of space used by children of this dataset, which would be freed if
818 all the dataset's children were destroyed.
820 The amount of space used by this dataset itself, which would be freed if the
821 dataset were destroyed
822 .Po after first removing any
824 and destroying any necessary snapshots or descendents
826 .It Sy usedbyrefreservation
827 The amount of space used by a
829 set on this dataset, which would be freed if the
832 .It Sy usedbysnapshots
833 The amount of space consumed by snapshots of this dataset.
834 In particular, it is the amount of space that would be freed if all of this
835 dataset's snapshots were destroyed.
836 Note that this is not simply the sum of the snapshots'
838 properties because space can be shared by multiple snapshots.
839 .It Sy userused Ns @ Ns Em user
840 The amount of space consumed by the specified user in this dataset.
841 Space is charged to the owner of each file, as displayed by
843 The amount of space charged is displayed by
849 subcommand for more information.
851 Unprivileged users can access only their own space usage.
852 The root user, or a user who has been granted the
856 can access everyone's usage.
859 .Sy userused Ns @ Ns Em ...
860 properties are not displayed by
861 .Nm zfs Cm get Sy all .
862 The user's name must be appended after the @ symbol, using one of the following
864 .Bl -bullet -width ""
878 .Sy joe.smith@mydomain
887 Files created on Linux always have POSIX owners.
888 .It Sy userobjused Ns @ Ns Em user
891 property is similar to
893 but instead it counts the number of objects consumed by a user. This property
894 counts all objects allocated on behalf of the user, it may differ from the
895 results of system tools such as
900 is set on a file system additional objects will be created per-file to store
901 extended attributes. These additional objects are reflected in the
903 value and are counted against the user's
905 When a file system is configured to use
907 no additional internal objects are normally required.
909 This property is set to the number of user holds on this snapshot.
910 User holds are set by using the
913 .It Sy groupused Ns @ Ns Em group
914 The amount of space consumed by the specified group in this dataset.
915 Space is charged to the group of each file, as displayed by
918 .Sy userused Ns @ Ns Em user
919 property for more information.
921 Unprivileged users can only access their own groups' space usage.
922 The root user, or a user who has been granted the
926 can access all groups' usage.
927 .It Sy groupobjused Ns @ Ns Em group
928 The number of objects consumed by the specified group in this dataset.
929 Multiple objects may be charged to the group for each file when extended
930 attributes are in use. See the
931 .Sy userobjused Ns @ Ns Em user
932 property for more information.
934 Unprivileged users can only access their own groups' space usage.
935 The root user, or a user who has been granted the
939 can access all groups' usage.
940 .It Sy projectused Ns @ Ns Em project
941 The amount of space consumed by the specified project in this dataset. Project
942 is identified via the project identifier (ID) that is object-based numeral
943 attribute. An object can inherit the project ID from its parent object (if the
944 parent has the flag of inherit project ID that can be set and changed via
947 .Nm zfs project Fl s )
948 when being created. The privileged user can set and change object's project
953 anytime. Space is charged to the project of each file, as displayed by
958 .Sy userused Ns @ Ns Em user
959 property for more information.
961 The root user, or a user who has been granted the
965 can access all projects' usage.
966 .It Sy projectobjused Ns @ Ns Em project
971 but instead it counts the number of objects consumed by project. When the
974 is set on a fileset, ZFS will create additional objects per-file to store
975 extended attributes. These additional objects are reflected in the
977 value and are counted against the project's
978 .Sy projectobjquota .
979 When a filesystem is configured to use
981 no additional internal objects are required. See the
982 .Sy userobjused Ns @ Ns Em user
983 property for more information.
985 The root user, or a user who has been granted the
989 can access all projects' objects usage.
991 For volumes, specifies the block size of the volume.
994 cannot be changed once the volume has been written, so it should be set at
995 volume creation time.
998 for volumes is 8 Kbytes.
999 Any power of 2 from 512 bytes to 128 Kbytes is valid.
1001 This property can also be referred to by its shortened column name,
1006 by this dataset, that was written since the previous snapshot
1007 .Pq i.e. that is not referenced by the previous snapshot .
1008 .It Sy written Ns @ Ns Em snapshot
1011 space written to this dataset since the specified snapshot.
1012 This is the space that is referenced by this dataset but was not referenced by
1013 the specified snapshot.
1017 may be specified as a short snapshot name
1018 .Po just the part after the
1021 in which case it will be interpreted as a snapshot in the same filesystem as
1025 may be a full snapshot name
1026 .Po Em filesystem Ns @ Ns Em snapshot Pc ,
1027 which for clones may be a snapshot in the origin's filesystem
1028 .Pq or the origin of the origin's filesystem, etc.
1031 The following native properties can be used to change the behavior of a ZFS
1035 .Sy aclinherit Ns = Ns Sy discard Ns | Ns Sy noallow Ns | Ns
1036 .Sy restricted Ns | Ns Sy passthrough Ns | Ns Sy passthrough-x
1038 Controls how ACEs are inherited when files and directories are created.
1039 .Bl -tag -width "passthrough-x"
1041 does not inherit any ACEs.
1043 only inherits inheritable ACEs that specify
1047 default, removes the
1051 permissions when the ACE is inherited.
1053 inherits all inheritable ACEs without any modifications.
1054 .It Sy passthrough-x
1062 ACEs inherit the execute permission only if the file creation mode also requests
1066 When the property value is set to
1068 files are created with a mode determined by the inheritable ACEs.
1069 If no inheritable ACEs exist that affect the mode, then the mode is set in
1070 accordance to the requested mode from the application.
1074 property does not apply to posix ACLs.
1075 .It Sy acltype Ns = Ns Sy off Ns | Ns Sy noacl Ns | Ns Sy posixacl
1076 Controls whether ACLs are enabled and if so what type of ACL to use.
1077 .Bl -tag -width "posixacl"
1079 default, when a file system has the
1081 property set to off then ACLs are disabled.
1086 indicates posix ACLs should be used. Posix ACLs are specific to Linux and are
1087 not functional on other platforms. Posix ACLs are stored as an extended
1088 attribute and therefore will not overwrite any existing NFSv4 ACLs which
1092 To obtain the best performance when setting
1094 users are strongly encouraged to set the
1096 property. This will result in the posix ACL being stored more efficiently on
1097 disk. But as a consequence of this all new extended attributes will only be
1098 accessible from OpenZFS implementations which support the
1102 property for more details.
1103 .It Sy atime Ns = Ns Sy on Ns | Ns Sy off
1104 Controls whether the access time for files is updated when they are read.
1105 Turning this property off avoids producing write traffic when reading files and
1106 can result in significant performance gains, though it might confuse mailers
1107 and other similar utilities. The values
1111 are equivalent to the
1115 mount options. The default value is
1120 .It Sy canmount Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy noauto
1121 If this property is set to
1123 the file system cannot be mounted, and is ignored by
1124 .Nm zfs Cm mount Fl a .
1125 Setting this property to
1127 is similar to setting the
1131 except that the dataset still has a normal
1133 property, which can be inherited.
1134 Setting this property to
1136 allows datasets to be used solely as a mechanism to inherit properties.
1137 One example of setting
1138 .Sy canmount Ns = Ns Sy off
1139 is to have two datasets with the same
1141 so that the children of both datasets appear in the same directory, but might
1142 have different inherited characteristics.
1146 a dataset can only be mounted and unmounted explicitly.
1147 The dataset is not mounted automatically when the dataset is created or
1148 imported, nor is it mounted by the
1149 .Nm zfs Cm mount Fl a
1150 command or unmounted by the
1151 .Nm zfs Cm unmount Fl a
1154 This property is not inherited.
1156 .Sy checksum Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy fletcher2 Ns | Ns
1157 .Sy fletcher4 Ns | Ns Sy sha256 Ns | Ns Sy noparity Ns | Ns
1158 .Sy sha512 Ns | Ns Sy skein Ns | Ns Sy edonr
1160 Controls the checksum used to verify data integrity.
1161 The default value is
1163 which automatically selects an appropriate algorithm
1166 but this may change in future releases
1170 disables integrity checking on user data.
1173 not only disables integrity but also disables maintaining parity for user data.
1174 This setting is used internally by a dump device residing on a RAID-Z pool and
1175 should not be used by any other dataset.
1176 Disabling checksums is
1178 a recommended practice.
1185 checksum algorithms require enabling the appropriate features on the pool.
1187 .Xr zpool-features 5
1188 for more information on these algorithms.
1190 Changing this property affects only newly-written data.
1192 Salted checksum algorithms
1193 .Pq Cm edonr , skein
1194 are currently not supported for any filesystem on the boot pools.
1196 .Sy compression Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy gzip Ns | Ns
1197 .Sy gzip- Ns Em N Ns | Ns Sy lz4 Ns | Ns Sy lzjb Ns | Ns Sy zle
1199 Controls the compression algorithm used for this dataset.
1201 Setting compression to
1203 indicates that the current default compression algorithm should be used.
1204 The default balances compression and decompression speed, with compression ratio
1205 and is expected to work well on a wide variety of workloads.
1206 Unlike all other settings for this property,
1208 does not select a fixed compression type.
1209 As new compression algorithms are added to ZFS and enabled on a pool, the
1210 default compression algorithm may change.
1211 The current default compression algorithm is either
1220 compression algorithm is a high-performance replacement for the
1223 It features significantly faster compression and decompression, as well as a
1224 moderately higher compression ratio than
1226 but can only be used on pools with the
1231 .Xr zpool-features 5
1232 for details on ZFS feature flags and the
1238 compression algorithm is optimized for performance while providing decent data
1243 compression algorithm uses the same compression as the
1248 level by using the value
1252 is an integer from 1
1255 .Pq best compression ratio .
1260 .Po which is also the default for
1266 compression algorithm compresses runs of zeros.
1268 This property can also be referred to by its shortened column name
1270 Changing this property affects only newly-written data.
1272 .Sy context Ns = Ns Sy none Ns | Ns
1273 .Em SELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level
1275 This flag sets the SELinux context for all files in the file system under
1276 a mount point for that file system. See
1278 for more information.
1280 .Sy fscontext Ns = Ns Sy none Ns | Ns
1281 .Em SELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level
1283 This flag sets the SELinux context for the file system file system being
1286 for more information.
1288 .Sy defcontext Ns = Ns Sy none Ns | Ns
1289 .Em SELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level
1291 This flag sets the SELinux default context for unlabeled files. See
1293 for more information.
1295 .Sy rootcontext Ns = Ns Sy none Ns | Ns
1296 .Em SELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level
1298 This flag sets the SELinux context for the root inode of the file system. See
1300 for more information.
1301 .It Sy copies Ns = Ns Sy 1 Ns | Ns Sy 2 Ns | Ns Sy 3
1302 Controls the number of copies of data stored for this dataset.
1303 These copies are in addition to any redundancy provided by the pool, for
1304 example, mirroring or RAID-Z.
1305 The copies are stored on different disks, if possible.
1306 The space used by multiple copies is charged to the associated file and dataset,
1309 property and counting against quotas and reservations.
1311 Changing this property only affects newly-written data.
1312 Therefore, set this property at file system creation time by using the
1313 .Fl o Sy copies Ns = Ns Ar N
1316 Remember that ZFS will not import a pool with a missing top-level vdev. Do
1318 create, for example a two-disk striped pool and set
1320 on some datasets thinking you have setup redundancy for them. When a disk
1321 fails you will not be able to import the pool and will have lost all of your
1323 .It Sy devices Ns = Ns Sy on Ns | Ns Sy off
1324 Controls whether device nodes can be opened on this file system.
1325 The default value is
1331 are equivalent to the
1337 .Sy dedup Ns = Ns Sy off Ns | Ns Sy on Ns | Ns Sy verify Ns | Ns
1338 .Sy sha256[,verify] Ns | Ns Sy sha512[,verify] Ns | Ns Sy skein[,verify] Ns | Ns
1341 Configures deduplication for a dataset. The default value is
1343 The default deduplication checksum is
1345 (this may change in the future). When
1347 is enabled, the checksum defined here overrides the
1349 property. Setting the value to
1351 has the same effect as the setting
1356 ZFS will do a byte-to-byte comparsion in case of two blocks having the same
1357 signature to make sure the block contents are identical. Specifying
1359 is mandatory for the
1363 Unless necessary, deduplication should NOT be enabled on a system. See
1367 .Sy dnodesize Ns = Ns Sy legacy Ns | Ns Sy auto Ns | Ns Sy 1k Ns | Ns
1368 .Sy 2k Ns | Ns Sy 4k Ns | Ns Sy 8k Ns | Ns Sy 16k
1370 Specifies a compatibility mode or literal value for the size of dnodes in the
1371 file system. The default value is
1373 Setting this property to a value other than
1375 requires the large_dnode pool feature to be enabled.
1381 if the dataset uses the
1383 property setting and the workload makes heavy use of extended attributes. This
1384 may be applicable to SELinux-enabled systems, Lustre servers, and Samba
1385 servers, for example. Literal values are supported for cases where the optimal
1386 size is known in advance and for performance testing.
1392 if you need to receive a send stream of this dataset on a pool that doesn't
1393 enable the large_dnode feature, or if you need to import this pool on a system
1394 that doesn't support the large_dnode feature.
1396 This property can also be referred to by its shortened column name,
1399 .Sy encryption Ns = Ns Sy off Ns | Ns Sy on Ns | Ns Sy aes-128-ccm Ns | Ns
1400 .Sy aes-192-ccm Ns | Ns Sy aes-256-ccm Ns | Ns Sy aes-128-gcm Ns | Ns
1401 .Sy aes-192-gcm Ns | Ns Sy aes-256-gcm
1403 Controls the encryption cipher suite (block cipher, key length, and mode) used
1404 for this dataset. Requires the
1406 feature to be enabled on the pool.
1409 to be set at dataset creation time.
1412 .Sy encryption Ns = Ns Sy on
1413 when creating a dataset indicates that the default encryption suite will be
1414 selected, which is currently
1416 In order to provide consistent data protection, encryption must be specified at
1417 dataset creation time and it cannot be changed afterwards.
1419 For more details and caveats about encryption see the
1422 .It Sy keyformat Ns = Ns Sy raw Ns | Ns Sy hex Ns | Ns Sy passphrase
1423 Controls what format the user's encryption key will be provided as. This
1424 property is only set when the dataset is encrypted.
1426 Raw keys and hex keys must be 32 bytes long (regardless of the chosen
1427 encryption suite) and must be randomly generated. A raw key can be generated
1428 with the following command:
1430 # dd if=/dev/urandom of=/path/to/output/key bs=32 count=1
1433 Passphrases must be between 8 and 512 bytes long and will be processed through
1434 PBKDF2 before being used (see the
1436 property). Even though the
1437 encryption suite cannot be changed after dataset creation, the keyformat can be
1439 .Nm zfs Cm change-key .
1441 .Sy keylocation Ns = Ns Sy prompt Ns | Ns Sy file:// Ns Em </absolute/file/path>
1443 Controls where the user's encryption key will be loaded from by default for
1447 .Nm zfs Cm mount Cm -l .
1448 This property is only set for encrypted datasets which are encryption roots. If
1449 unspecified, the default is
1452 Even though the encryption suite cannot be changed after dataset creation, the
1453 keylocation can be with either
1456 .Nm zfs Cm change-key .
1459 is selected ZFS will ask for the key at the command prompt when it is required
1460 to access the encrypted data (see
1462 for details). This setting will also allow the key to be passed in via STDIN,
1463 but users should be careful not to place keys which should be kept secret on
1464 the command line. If a file URI is selected, the key will be loaded from the
1465 specified absolute file path.
1466 .It Sy pbkdf2iters Ns = Ns Ar iterations
1467 Controls the number of PBKDF2 iterations that a
1469 encryption key should be run through when processing it into an encryption key.
1470 This property is only defined when encryption is enabled and a keyformat of
1472 is selected. The goal of PBKDF2 is to significantly increase the
1473 computational difficulty needed to brute force a user's passphrase. This is
1474 accomplished by forcing the attacker to run each passphrase through a
1475 computationally expensive hashing function many times before they arrive at the
1476 resulting key. A user who actually knows the passphrase will only have to pay
1477 this cost once. As CPUs become better at processing, this number should be
1478 raised to ensure that a brute force attack is still not possible. The current
1483 This property may be changed with
1484 .Nm zfs Cm change-key .
1485 .It Sy exec Ns = Ns Sy on Ns | Ns Sy off
1486 Controls whether processes can be executed from within this file system.
1487 The default value is
1493 are equivalent to the
1498 .It Sy filesystem_limit Ns = Ns Em count Ns | Ns Sy none
1499 Limits the number of filesystems and volumes that can exist under this point in
1501 The limit is not enforced if the user is allowed to change the limit.
1503 .Sy filesystem_limit
1506 a descendent of a filesystem that already has a
1507 .Sy filesystem_limit
1508 does not override the ancestor's
1509 .Sy filesystem_limit ,
1510 but rather imposes an additional limit.
1511 This feature must be enabled to be used
1513 .Xr zpool-features 5
1515 .It Sy mountpoint Ns = Ns Pa path Ns | Ns Sy none Ns | Ns Sy legacy
1516 Controls the mount point used for this file system.
1519 section for more information on how this property is used.
1523 property is changed for a file system, the file system and any children that
1524 inherit the mount point are unmounted.
1527 then they remain unmounted.
1528 Otherwise, they are automatically remounted in the new location if the property
1533 or if they were mounted before the property was changed.
1534 In addition, any shared file systems are unshared and shared in the new
1536 .It Sy nbmand Ns = Ns Sy on Ns | Ns Sy off
1537 Controls whether the file system should be mounted with
1539 .Pq Non Blocking mandatory locks .
1540 This is used for SMB clients.
1541 Changes to this property only take effect when the file system is umounted and
1545 for more information on
1547 mounts. This property is not used on Linux.
1548 .It Sy overlay Ns = Ns Sy off Ns | Ns Sy on
1549 Allow mounting on a busy directory or a directory which already contains
1550 files or directories. This is the default mount behavior for Linux file systems.
1551 For consistency with OpenZFS on other platforms overlay mounts are
1555 to enable overlay mounts.
1556 .It Sy primarycache Ns = Ns Sy all Ns | Ns Sy none Ns | Ns Sy metadata
1557 Controls what is cached in the primary cache
1559 If this property is set to
1561 then both user data and metadata is cached.
1562 If this property is set to
1564 then neither user data nor metadata is cached.
1565 If this property is set to
1567 then only metadata is cached.
1568 The default value is
1570 .It Sy quota Ns = Ns Em size Ns | Ns Sy none
1571 Limits the amount of space a dataset and its descendents can consume.
1572 This property enforces a hard limit on the amount of space used.
1573 This includes all space consumed by descendents, including file systems and
1575 Setting a quota on a descendent of a dataset that already has a quota does not
1576 override the ancestor's quota, but rather imposes an additional limit.
1578 Quotas cannot be set on volumes, as the
1580 property acts as an implicit quota.
1581 .It Sy snapshot_limit Ns = Ns Em count Ns | Ns Sy none
1582 Limits the number of snapshots that can be created on a dataset and its
1586 on a descendent of a dataset that already has a
1588 does not override the ancestor's
1589 .Sy snapshot_limit ,
1590 but rather imposes an additional limit.
1591 The limit is not enforced if the user is allowed to change the limit.
1592 For example, this means that recursive snapshots taken from the global zone are
1593 counted against each delegated dataset within a zone.
1594 This feature must be enabled to be used
1596 .Xr zpool-features 5
1598 .It Sy userquota@ Ns Em user Ns = Ns Em size Ns | Ns Sy none
1599 Limits the amount of space consumed by the specified user.
1600 User space consumption is identified by the
1601 .Sy userspace@ Ns Em user
1604 Enforcement of user quotas may be delayed by several seconds.
1605 This delay means that a user might exceed their quota before the system notices
1606 that they are over quota and begins to refuse additional writes with the
1610 .Nm zfs Cm userspace
1611 subcommand for more information.
1613 Unprivileged users can only access their own groups' space usage.
1614 The root user, or a user who has been granted the
1618 can get and set everyone's quota.
1620 This property is not available on volumes, on file systems before version 4, or
1621 on pools before version 15.
1623 .Sy userquota@ Ns Em ...
1624 properties are not displayed by
1625 .Nm zfs Cm get Sy all .
1626 The user's name must be appended after the
1628 symbol, using one of the following forms:
1636 .Em POSIX numeric ID
1643 .Sy joe.smith@mydomain
1652 Files created on Linux always have POSIX owners.
1653 .It Sy userobjquota@ Ns Em user Ns = Ns Em size Ns | Ns Sy none
1658 but it limits the number of objects a user can create. Please refer to
1660 for more information about how objects are counted.
1661 .It Sy groupquota@ Ns Em group Ns = Ns Em size Ns | Ns Sy none
1662 Limits the amount of space consumed by the specified group.
1663 Group space consumption is identified by the
1664 .Sy groupused@ Ns Em group
1667 Unprivileged users can access only their own groups' space usage.
1668 The root user, or a user who has been granted the
1672 can get and set all groups' quotas.
1673 .It Sy groupobjquota@ Ns Em group Ns = Ns Em size Ns | Ns Sy none
1678 but it limits number of objects a group can consume. Please refer to
1680 for more information about how objects are counted.
1681 .It Sy projectquota@ Ns Em project Ns = Ns Em size Ns | Ns Sy none
1682 Limits the amount of space consumed by the specified project. Project
1683 space consumption is identified by the
1684 .Sy projectused@ Ns Em project
1685 property. Please refer to
1687 for more information about how project is identified and set/changed.
1689 The root user, or a user who has been granted the
1693 can access all projects' quota.
1694 .It Sy projectobjquota@ Ns Em project Ns = Ns Em size Ns | Ns Sy none
1699 but it limits number of objects a project can consume. Please refer to
1701 for more information about how objects are counted.
1702 .It Sy readonly Ns = Ns Sy on Ns | Ns Sy off
1703 Controls whether this dataset can be modified.
1704 The default value is
1710 are equivalent to the
1716 This property can also be referred to by its shortened column name,
1718 .It Sy recordsize Ns = Ns Em size
1719 Specifies a suggested block size for files in the file system.
1720 This property is designed solely for use with database workloads that access
1721 files in fixed-size records.
1722 ZFS automatically tunes block sizes according to internal algorithms optimized
1723 for typical access patterns.
1725 For databases that create very large files but access them in small random
1726 chunks, these algorithms may be suboptimal.
1729 greater than or equal to the record size of the database can result in
1730 significant performance gains.
1731 Use of this property for general purpose file systems is strongly discouraged,
1732 and may adversely affect performance.
1734 The size specified must be a power of two greater than or equal to 512 and less
1735 than or equal to 128 Kbytes.
1738 feature is enabled on the pool, the size may be up to 1 Mbyte.
1740 .Xr zpool-features 5
1741 for details on ZFS feature flags.
1743 Changing the file system's
1745 affects only files created afterward; existing files are unaffected.
1747 This property can also be referred to by its shortened column name,
1749 .It Sy redundant_metadata Ns = Ns Sy all Ns | Ns Sy most
1750 Controls what types of metadata are stored redundantly.
1751 ZFS stores an extra copy of metadata, so that if a single block is corrupted,
1752 the amount of user data lost is limited.
1753 This extra copy is in addition to any redundancy provided at the pool level
1754 .Pq e.g. by mirroring or RAID-Z ,
1755 and is in addition to an extra copy specified by the
1758 .Pq up to a total of 3 copies .
1759 For example if the pool is mirrored,
1760 .Sy copies Ns = Ns 2 ,
1762 .Sy redundant_metadata Ns = Ns Sy most ,
1763 then ZFS stores 6 copies of most metadata, and 4 copies of data and some
1768 ZFS stores an extra copy of all metadata.
1769 If a single on-disk block is corrupt, at worst a single block of user data
1778 ZFS stores an extra copy of most types of metadata.
1779 This can improve performance of random writes, because less metadata must be
1781 In practice, at worst about 100 blocks
1786 of user data can be lost if a single on-disk block is corrupt.
1787 The exact behavior of which metadata blocks are stored redundantly may change in
1790 The default value is
1792 .It Sy refquota Ns = Ns Em size Ns | Ns Sy none
1793 Limits the amount of space a dataset can consume.
1794 This property enforces a hard limit on the amount of space used.
1795 This hard limit does not include space used by descendents, including file
1796 systems and snapshots.
1797 .It Sy refreservation Ns = Ns Em size Ns | Ns Sy none Ns | Ns Sy auto
1798 The minimum amount of space guaranteed to a dataset, not including its
1800 When the amount of space used is below this value, the dataset is treated as if
1801 it were taking up the amount of space specified by
1802 .Sy refreservation .
1805 reservation is accounted for in the parent datasets' space used, and counts
1806 against the parent datasets' quotas and reservations.
1810 is set, a snapshot is only allowed if there is enough free pool space outside of
1811 this reservation to accommodate the current number of
1813 bytes in the dataset.
1819 a volume is thick provisioned
1823 .Sy refreservation Ns = Ns Sy auto
1824 is only supported on volumes.
1828 .Sx Native Properties
1829 section for more information about sparse volumes.
1831 This property can also be referred to by its shortened column name,
1833 .It Sy relatime Ns = Ns Sy on Ns | Ns Sy off
1834 Controls the manner in which the access time is updated when
1836 is set. Turning this property on causes the access time to be updated relative
1837 to the modify or change time. Access time is only updated if the previous
1838 access time was earlier than the current modify or change time or if the
1839 existing access time hasn't been updated within the past 24 hours. The default
1846 are equivalent to the
1851 .It Sy reservation Ns = Ns Em size Ns | Ns Sy none
1852 The minimum amount of space guaranteed to a dataset and its descendants.
1853 When the amount of space used is below this value, the dataset is treated as if
1854 it were taking up the amount of space specified by its reservation.
1855 Reservations are accounted for in the parent datasets' space used, and count
1856 against the parent datasets' quotas and reservations.
1858 This property can also be referred to by its shortened column name,
1860 .It Sy secondarycache Ns = Ns Sy all Ns | Ns Sy none Ns | Ns Sy metadata
1861 Controls what is cached in the secondary cache
1863 If this property is set to
1865 then both user data and metadata is cached.
1866 If this property is set to
1868 then neither user data nor metadata is cached.
1869 If this property is set to
1871 then only metadata is cached.
1872 The default value is
1874 .It Sy setuid Ns = Ns Sy on Ns | Ns Sy off
1875 Controls whether the setuid bit is respected for the file system.
1876 The default value is
1882 are equivalent to the
1887 .It Sy sharesmb Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Em opts
1888 Controls whether the file system is shared by using
1889 .Sy Samba USERSHARES
1890 and what options are to be used. Otherwise, the file system is automatically
1891 shared and unshared with the
1895 commands. If the property is set to on, the
1897 command is invoked to create a
1900 Because SMB shares requires a resource name, a unique resource name is
1901 constructed from the dataset name. The constructed name is a copy of the
1902 dataset name except that the characters in the dataset name, which would be
1903 invalid in the resource name, are replaced with underscore (_) characters.
1904 Linux does not currently support additional options which might be available
1911 the file systems are unshared.
1913 The share is created with the ACL (Access Control List) "Everyone:F" ("F"
1914 stands for "full permissions", ie. read and write permissions) and no guest
1915 access (which means Samba must be able to authenticate a real user, system
1916 passwd/shadow, LDAP or smbpasswd based) by default. This means that any
1917 additional access control (disallow specific user specific access etc) must
1918 be done on the underlying file system.
1919 .It Sy sharenfs Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Em opts
1920 Controls whether the file system is shared via NFS, and what options are to be
1922 A file system with a
1928 command and entries in the
1931 Otherwise, the file system is automatically shared and unshared with the
1936 If the property is set to
1938 the dataset is shared using the default options:
1940 .Em sec=sys,rw,crossmnt,no_subtree_check,no_root_squash
1944 for the meaning of the default options. Otherwise, the
1946 command is invoked with options equivalent to the contents of this property.
1950 property is changed for a dataset, the dataset and any children inheriting the
1951 property are re-shared with the new options, only if the property was previously
1953 or if they were shared before the property was changed.
1954 If the new property is
1956 the file systems are unshared.
1957 .It Sy logbias Ns = Ns Sy latency Ns | Ns Sy throughput
1958 Provide a hint to ZFS about handling of synchronous requests in this dataset.
1964 ZFS will use pool log devices
1966 to handle the requests at low latency.
1971 ZFS will not use configured pool log devices.
1972 ZFS will instead optimize synchronous operations for global pool throughput and
1973 efficient use of resources.
1974 .It Sy snapdev Ns = Ns Sy hidden Ns | Ns Sy visible
1975 Controls whether the volume snapshot devices under
1976 .Em /dev/zvol/<pool>
1977 are hidden or visible. The default value is
1979 .It Sy snapdir Ns = Ns Sy hidden Ns | Ns Sy visible
1980 Controls whether the
1982 directory is hidden or visible in the root of the file system as discussed in
1986 The default value is
1988 .It Sy sync Ns = Ns Sy standard Ns | Ns Sy always Ns | Ns Sy disabled
1989 Controls the behavior of synchronous requests
1990 .Pq e.g. fsync, O_DSYNC .
1994 specified behavior of ensuring all synchronous requests are written to stable
1995 storage and all devices are flushed to ensure data is not cached by device
1997 .Pq this is the default .
1999 causes every file system transaction to be written and flushed before its
2000 system call returns.
2001 This has a large performance penalty.
2003 disables synchronous requests.
2004 File system transactions are only committed to stable storage periodically.
2005 This option will give the highest performance.
2006 However, it is very dangerous as ZFS would be ignoring the synchronous
2007 transaction demands of applications such as databases or NFS.
2008 Administrators should only use this option when the risks are understood.
2009 .It Sy version Ns = Ns Em N Ns | Ns Sy current
2010 The on-disk version of this file system, which is independent of the pool
2012 This property can only be set to later supported versions.
2016 .It Sy volsize Ns = Ns Em size
2017 For volumes, specifies the logical size of the volume.
2018 By default, creating a volume establishes a reservation of equal size.
2019 For storage pools with a version number of 9 or higher, a
2024 are reflected in an equivalent change to the reservation
2030 can only be set to a multiple of
2034 The reservation is kept equal to the volume's logical size to prevent unexpected
2035 behavior for consumers.
2036 Without the reservation, the volume could run out of space, resulting in
2037 undefined behavior or data corruption, depending on how the volume is used.
2038 These effects can also occur when the volume size is changed while it is in use
2039 .Pq particularly when shrinking the size .
2040 Extreme care should be used when adjusting the volume size.
2042 Though not recommended, a
2045 .Qq thin provisioned
2047 can be created by specifying the
2050 .Nm zfs Cm create Fl V
2051 command, or by changing the value of the
2056 property on pool version 8 or earlier
2058 after the volume has been created.
2061 is a volume where the value of
2063 is less than the size of the volume plus the space required to store its
2065 Consequently, writes to a sparse volume can fail with
2067 when the pool is low on space.
2068 For a sparse volume, changes to
2070 are not reflected in the
2072 A volume that is not sparse is said to be
2073 .Qq thick provisioned .
2074 A sparse volume can become thick provisioned by setting
2078 .It Sy volmode Ns = Ns Cm default | full | geom | dev | none
2079 This property specifies how volumes should be exposed to the OS.
2082 exposes volumes as fully fledged block devices, providing maximal
2083 functionality. The value
2085 is just an alias for
2087 and is kept for compatibility.
2090 hides its partitions.
2091 Volumes with property set to
2093 are not exposed outside ZFS, but can be snapshoted, cloned, replicated, etc,
2094 that can be suitable for backup purposes.
2097 means that volumes exposition is controlled by system-wide tunable
2104 are encoded as 1, 2 and 3 respectively.
2105 The default values is
2107 .It Sy vscan Ns = Ns Sy on Ns | Ns Sy off
2108 Controls whether regular files should be scanned for viruses when a file is
2110 In addition to enabling this property, the virus scan service must also be
2111 enabled for virus scanning to occur.
2112 The default value is
2114 This property is not used on Linux.
2115 .It Sy xattr Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy sa
2116 Controls whether extended attributes are enabled for this file system. Two
2117 styles of extended attributes are supported either directory based or system
2120 The default value of
2122 enables directory based extended attributes. This style of extended attribute
2123 imposes no practical limit on either the size or number of attributes which
2124 can be set on a file. Although under Linux the
2128 system calls limit the maximum size to 64K. This is the most compatible
2129 style of extended attribute and is supported by all OpenZFS implementations.
2131 System attribute based xattrs can be enabled by setting the value to
2133 The key advantage of this type of xattr is improved performance. Storing
2134 extended attributes as system attributes significantly decreases the amount of
2135 disk IO required. Up to 64K of data may be stored per-file in the space
2136 reserved for system attributes. If there is not enough space available for
2137 an extended attribute then it will be automatically written as a directory
2138 based xattr. System attribute based extended attributes are not accessible
2139 on platforms which do not support the
2143 The use of system attribute based xattrs is strongly encouraged for users of
2144 SELinux or posix ACLs. Both of these features heavily rely of extended
2145 attributes and benefit significantly from the reduced access time.
2151 are equivalent to the
2156 .It Sy zoned Ns = Ns Sy on Ns | Ns Sy off
2157 Controls whether the dataset is managed from a non-global zone. Zones are a
2158 Solaris feature and are not relevant on Linux. The default value is
2162 The following three properties cannot be changed after the file system is
2163 created, and therefore, should be set when the file system is created.
2164 If the properties are not set with the
2168 commands, these properties are inherited from the parent dataset.
2169 If the parent dataset lacks these properties due to having been created prior to
2170 these features being supported, the new file system will have the default values
2171 for these properties.
2174 .Sy casesensitivity Ns = Ns Sy sensitive Ns | Ns
2175 .Sy insensitive Ns | Ns Sy mixed
2177 Indicates whether the file name matching algorithm used by the file system
2178 should be case-sensitive, case-insensitive, or allow a combination of both
2180 The default value for the
2188 file systems have case-sensitive file names.
2194 property indicates that the file system can support requests for both
2195 case-sensitive and case-insensitive matching behavior.
2196 Currently, case-insensitive matching behavior on a file system that supports
2197 mixed behavior is limited to the SMB server product.
2198 For more information about the
2200 value behavior, see the "ZFS Administration Guide".
2202 .Sy normalization Ns = Ns Sy none Ns | Ns Sy formC Ns | Ns
2203 .Sy formD Ns | Ns Sy formKC Ns | Ns Sy formKD
2205 Indicates whether the file system should perform a
2207 normalization of file names whenever two file names are compared, and which
2208 normalization algorithm should be used.
2209 File names are always stored unmodified, names are normalized as part of any
2211 If this property is set to a legal value other than
2215 property was left unspecified, the
2217 property is automatically set to
2219 The default value of the
2223 This property cannot be changed after the file system is created.
2224 .It Sy utf8only Ns = Ns Sy on Ns | Ns Sy off
2225 Indicates whether the file system should reject file names that include
2226 characters that are not present in the
2229 If this property is explicitly set to
2231 the normalization property must either not be explicitly set or be set to
2233 The default value for the
2237 This property cannot be changed after the file system is created.
2241 .Sy casesensitivity ,
2245 properties are also new permissions that can be assigned to non-privileged users
2246 by using the ZFS delegated administration feature.
2247 .Ss "Temporary Mount Point Properties"
2248 When a file system is mounted, either through
2250 for legacy mounts or the
2252 command for normal file systems, its mount options are set according to its
2254 The correlation between properties and mount options is as follows:
2256 PROPERTY MOUNT OPTION
2258 canmount auto/noauto
2262 relatime relatime/norelatime
2267 In addition, these options can be set on a per-mount basis using the
2269 option, without affecting the property that is stored on disk.
2270 The values specified on the command line override the values stored in the
2274 option is an alias for
2275 .Sy nodevices Ns \&, Ns Sy nosetuid .
2276 These properties are reported as
2281 If the properties are changed while the dataset is mounted, the new setting
2282 overrides any temporary settings.
2283 .Ss "User Properties"
2284 In addition to the standard native properties, ZFS supports arbitrary user
2286 User properties have no effect on ZFS behavior, but applications or
2287 administrators can use them to annotate datasets
2288 .Pq file systems, volumes, and snapshots .
2290 User property names must contain a colon
2292 character to distinguish them from native properties.
2293 They may contain lowercase letters, numbers, and the following punctuation
2302 The expected convention is that the property name is divided into two portions
2304 .Em module Ns \&: Ns Em property ,
2305 but this namespace is not enforced by ZFS.
2306 User property names can be at most 256 characters, and cannot begin with a dash
2309 When making programmatic use of user properties, it is strongly suggested to use
2314 component of property names to reduce the chance that two
2315 independently-developed packages use the same property name for different
2318 The values of user properties are arbitrary strings, are always inherited, and
2319 are never validated.
2320 All of the commands that operate on properties
2321 .Po Nm zfs Cm list ,
2326 can be used to manipulate both native properties and user properties.
2329 command to clear a user property.
2330 If the property is not defined in any parent dataset, it is removed entirely.
2331 Property values are limited to 8192 bytes.
2332 .Ss ZFS Volumes as Swap
2333 ZFS volumes may be used as swap devices. After creating the volume with the
2334 .Nm zfs Cm create Fl V
2335 command set up and enable the swap area using the
2339 commands. Do not swap to a file on a ZFS file system. A ZFS swap file
2340 configuration is not supported.
2344 feature allows for the creation of encrypted filesystems and volumes.
2346 will encrypt all user data including file and zvol data, file attributes,
2347 ACLs, permission bits, directory listings, FUID mappings, and userused /
2350 will not encrypt metadata related to the pool structure, including dataset
2351 names, dataset hierarchy, file size, file holes, and dedup tables. Key rotation
2352 is managed internally by the kernel module and changing the user's key does not
2353 require re-encrypting the entire dataset. Datasets can be scrubbed, resilvered,
2354 renamed, and deleted without the encryption keys being loaded (see the
2356 subcommand for more info on key loading).
2358 Creating an encrypted dataset requires specifying the
2362 properties at creation time, along with an optional
2366 After entering an encryption key, the
2367 created dataset will become an encryption root. Any descendant datasets will
2368 inherit their encryption key from the encryption root by default, meaning that
2369 loading, unloading, or changing the key for the encryption root will implicitly
2370 do the same for all inheriting datasets. If this inheritance is not desired,
2373 when creating the child dataset or use
2374 .Nm zfs Cm change-key
2375 to break an existing relationship, creating a new encryption root on the child.
2376 Note that the child's
2378 may match that of the parent while still creating a new encryption root, and
2381 property alone does not create a new encryption root; this would simply use a
2382 different cipher suite with the same key as its encryption root. The one
2383 exception is that clones will always use their origin's encryption key.
2384 As a result of this exception, some encryption-related properties (namely
2390 do not inherit like other ZFS properties and instead use the value determined
2391 by their encryption root. Encryption root inheritance can be tracked via the
2396 Encryption changes the behavior of a few
2398 operations. Encryption is applied after compression so compression ratios are
2399 preserved. Normally checksums in ZFS are 256 bits long, but for encrypted data
2400 the checksum is 128 bits of the user-chosen checksum and 128 bits of MAC from
2401 the encryption suite, which provides additional protection against maliciously
2402 altered data. Deduplication is still possible with encryption enabled but for
2403 security, datasets will only dedup against themselves, their snapshots, and
2406 There are a few limitations on encrypted datasets. Encrypted data cannot be
2409 feature. Encrypted datasets may not have
2410 .Sy copies Ns = Ns Em 3
2411 since the implementation stores some encryption metadata where the third copy
2412 would normally be. Since compression is applied before encryption datasets may
2413 be vulnerable to a CRIME-like attack if applications accessing the data allow
2414 for it. Deduplication with encryption will leak information about which blocks
2415 are equivalent in a dataset and will incur an extra CPU cost per block written.
2417 All subcommands that modify state are logged persistently to the pool in their
2421 Displays a help message.
2426 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
2429 Creates a new ZFS file system.
2430 The file system is automatically mounted according to the
2432 property inherited from the parent.
2433 .Bl -tag -width "-o"
2434 .It Fl o Ar property Ns = Ns Ar value
2435 Sets the specified property as if the command
2436 .Nm zfs Cm set Ar property Ns = Ns Ar value
2437 was invoked at the same time the dataset was created.
2438 Any editable ZFS property can also be set at creation time.
2441 options can be specified.
2442 An error results if the same property is specified in multiple
2446 Creates all the non-existing parent datasets.
2447 Datasets created in this manner are automatically mounted according to the
2449 property inherited from their parent.
2450 Any property specified on the command line using the
2453 If the target filesystem already exists, the operation completes successfully.
2459 .Op Fl b Ar blocksize
2460 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
2461 .Fl V Ar size Ar volume
2463 Creates a volume of the given size.
2464 The volume is exported as a block device in
2465 .Pa /dev/zvol/path ,
2468 is the name of the volume in the ZFS namespace.
2469 The size represents the logical size as exported by the device.
2470 By default, a reservation of equal size is created.
2473 is automatically rounded up to the nearest 128 Kbytes to ensure that the volume
2474 has an integral number of blocks regardless of
2476 .Bl -tag -width "-b"
2477 .It Fl b Ar blocksize
2479 .Fl o Sy volblocksize Ns = Ns Ar blocksize .
2480 If this option is specified in conjunction with
2481 .Fl o Sy volblocksize ,
2482 the resulting behavior is undefined.
2483 .It Fl o Ar property Ns = Ns Ar value
2484 Sets the specified property as if the
2485 .Nm zfs Cm set Ar property Ns = Ns Ar value
2486 command was invoked at the same time the dataset was created.
2487 Any editable ZFS property can also be set at creation time.
2490 options can be specified.
2491 An error results if the same property is specified in multiple
2495 Creates all the non-existing parent datasets.
2496 Datasets created in this manner are automatically mounted according to the
2498 property inherited from their parent.
2499 Any property specified on the command line using the
2502 If the target filesystem already exists, the operation completes successfully.
2504 Creates a sparse volume with no reservation.
2508 .Sx Native Properties
2509 section for more information about sparse volumes.
2515 .Ar filesystem Ns | Ns Ar volume
2517 Destroys the given dataset.
2518 By default, the command unshares any file systems that are currently shared,
2519 unmounts any file systems that are currently mounted, and refuses to destroy a
2520 dataset that has active dependents
2521 .Pq children or clones .
2522 .Bl -tag -width "-R"
2524 Recursively destroy all dependents, including cloned file systems outside the
2527 Force an unmount of any file systems using the
2530 This option has no effect on non-file systems or unmounted file systems.
2535 No data will be deleted.
2536 This is useful in conjunction with the
2540 flags to determine what data would be deleted.
2542 Print machine-parsable verbose information about the deleted data.
2544 Recursively destroy all children.
2546 Print verbose information about the deleted data.
2549 Extreme care should be taken when applying either the
2553 options, as they can destroy large portions of a pool and cause unexpected
2554 behavior for mounted file systems in use.
2559 .Ar filesystem Ns | Ns Ar volume Ns @ Ns Ar snap Ns
2560 .Oo % Ns Ar snap Ns Oo , Ns Ar snap Ns Oo % Ns Ar snap Oc Oc Oc Ns ...
2562 The given snapshots are destroyed immediately if and only if the
2566 option would have destroyed it.
2567 Such immediate destruction would occur, for example, if the snapshot had no
2568 clones and the user-initiated reference count were zero.
2570 If a snapshot does not qualify for immediate destruction, it is marked for
2572 In this state, it exists as a usable, visible snapshot until both of the
2573 preconditions listed above are met, at which point it is destroyed.
2575 An inclusive range of snapshots may be specified by separating the first and
2576 last snapshots with a percent sign.
2577 The first and/or last snapshots may be left blank, in which case the
2578 filesystem's oldest or newest snapshot will be implied.
2581 .Pq or ranges of snapshots
2582 of the same filesystem or volume may be specified in a comma-separated list of
2584 Only the snapshot's short name
2585 .Po the part after the
2588 should be specified when using a range or comma-separated list to identify
2590 .Bl -tag -width "-R"
2592 Recursively destroy all clones of these snapshots, including the clones,
2593 snapshots, and children.
2594 If this flag is specified, the
2596 flag will have no effect.
2598 Destroy immediately. If a snapshot cannot be destroyed now, mark it for
2599 deferred destruction.
2604 No data will be deleted.
2605 This is useful in conjunction with the
2609 flags to determine what data would be deleted.
2611 Print machine-parsable verbose information about the deleted data.
2614 .Pq or mark for deferred deletion
2615 all snapshots with this name in descendent file systems.
2617 Print verbose information about the deleted data.
2619 Extreme care should be taken when applying either the
2623 options, as they can destroy large portions of a pool and cause unexpected
2624 behavior for mounted file systems in use.
2629 .Ar filesystem Ns | Ns Ar volume Ns # Ns Ar bookmark
2631 The given bookmark is destroyed.
2636 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
2637 .Ar filesystem Ns @ Ns Ar snapname Ns | Ns Ar volume Ns @ Ns Ar snapname Ns ...
2639 Creates snapshots with the given names.
2640 All previous modifications by successful system calls to the file system are
2641 part of the snapshots.
2642 Snapshots are taken atomically, so that all snapshots correspond to the same
2645 can be used as an alias for
2646 .Nm zfs Cm snapshot.
2649 section for details.
2650 .Bl -tag -width "-o"
2651 .It Fl o Ar property Ns = Ns Ar value
2652 Sets the specified property; see
2656 Recursively create snapshots of all descendent datasets
2664 Roll back the given dataset to a previous snapshot.
2665 When a dataset is rolled back, all data that has changed since the snapshot is
2666 discarded, and the dataset reverts to the state at the time of the snapshot.
2667 By default, the command refuses to roll back to a snapshot other than the most
2669 In order to do so, all intermediate snapshots and bookmarks must be destroyed by
2676 options do not recursively destroy the child snapshots of a recursive snapshot.
2677 Only direct snapshots of the specified filesystem are destroyed by either of
2679 To completely roll back a recursive snapshot, you must rollback the individual
2681 .Bl -tag -width "-R"
2683 Destroy any more recent snapshots and bookmarks, as well as any clones of those
2688 option to force an unmount of any clone file systems that are to be destroyed.
2690 Destroy any snapshots and bookmarks more recent than the one specified.
2696 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
2697 .Ar snapshot Ar filesystem Ns | Ns Ar volume
2699 Creates a clone of the given snapshot.
2702 section for details.
2703 The target dataset can be located anywhere in the ZFS hierarchy, and is created
2704 as the same type as the original.
2705 .Bl -tag -width "-o"
2706 .It Fl o Ar property Ns = Ns Ar value
2707 Sets the specified property; see
2711 Creates all the non-existing parent datasets.
2712 Datasets created in this manner are automatically mounted according to the
2714 property inherited from their parent.
2715 If the target filesystem or volume already exists, the operation completes
2721 .Ar clone-filesystem
2723 Promotes a clone file system to no longer be dependent on its
2726 This makes it possible to destroy the file system that the clone was created
2728 The clone parent-child dependency relationship is reversed, so that the origin
2729 file system becomes a clone of the specified file system.
2731 The snapshot that was cloned, and any snapshots previous to this snapshot, are
2732 now owned by the promoted clone.
2733 The space they use moves from the origin file system to the promoted clone, so
2734 enough space must be available to accommodate these snapshots.
2735 No new space is consumed by this operation, but the space accounting is
2737 The promoted clone must not have any conflicting snapshot names of its own.
2740 subcommand can be used to rename any conflicting snapshots.
2745 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2746 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2752 .Ar filesystem Ns | Ns Ar volume
2753 .Ar filesystem Ns | Ns Ar volume
2755 Renames the given dataset.
2756 The new target can be located anywhere in the ZFS hierarchy, with the exception
2758 Snapshots can only be renamed within the parent file system or volume.
2759 When renaming a snapshot, the parent file system of the snapshot does not need
2760 to be specified as part of the second argument.
2761 Renamed file systems can inherit new mount points, in which case they are
2762 unmounted and remounted at the new mount point.
2763 .Bl -tag -width "-a"
2765 Force unmount any filesystems that need to be unmounted in the process.
2767 Creates all the nonexistent parent datasets.
2768 Datasets created in this manner are automatically mounted according to the
2770 property inherited from their parent.
2776 .Ar snapshot Ar snapshot
2778 Recursively rename the snapshots of all descendent datasets.
2779 Snapshots are the only dataset that can be renamed recursively.
2783 .Op Fl r Ns | Ns Fl d Ar depth
2785 .Oo Fl o Ar property Ns Oo , Ns Ar property Oc Ns ... Oc
2786 .Oo Fl s Ar property Oc Ns ...
2787 .Oo Fl S Ar property Oc Ns ...
2788 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2789 .Oo Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Oc Ns ...
2791 Lists the property information for the given datasets in tabular form.
2792 If specified, you can list property information by the absolute pathname or the
2794 By default, all file systems and volumes are displayed.
2795 Snapshots are displayed if the
2802 The following fields are displayed:
2803 .Sy name Ns \&, Sy used Ns \&, Sy available Ns \&, Sy referenced Ns \&, Sy mountpoint Ns .
2804 .Bl -tag -width "-H"
2806 Used for scripting mode.
2807 Do not print headers and separate fields by a single tab instead of arbitrary
2809 .It Fl S Ar property
2812 option, but sorts by property in descending order.
2814 Recursively display any children of the dataset, limiting the recursion to
2820 will display only the dataset and its direct children.
2821 .It Fl o Ar property
2822 A comma-separated list of properties to display.
2823 The property must be:
2826 One of the properties described in the
2827 .Sx Native Properties
2834 to display the dataset name
2838 to display space usage properties on file systems and volumes.
2839 This is a shortcut for specifying
2840 .Fl o Sy name Ns \&, Ns Sy avail Ns \&, Ns Sy used Ns \&, Ns Sy usedsnap Ns \&, Ns
2841 .Sy usedds Ns \&, Ns Sy usedrefreserv Ns \&, Ns Sy usedchild Fl t
2842 .Sy filesystem Ns \&, Ns Sy volume
2846 Display numbers in parsable
2850 Recursively display any children of the dataset on the command line.
2851 .It Fl s Ar property
2852 A property for sorting the output by column in ascending order based on the
2853 value of the property.
2854 The property must be one of the properties described in the
2856 section, or the special value
2858 to sort by the dataset name.
2859 Multiple properties can be specified at one time using multiple
2864 options are evaluated from left to right in decreasing order of importance.
2865 The following is a list of sorting criteria:
2868 Numeric types sort in numeric order.
2870 String types sort in alphabetical order.
2872 Types inappropriate for a row sort that row to the literal bottom, regardless of
2873 the specified ordering.
2876 If no sorting options are specified the existing behavior of
2880 A comma-separated list of types to display, where
2889 For example, specifying
2891 displays only snapshots.
2896 .Ar property Ns = Ns Ar value Oo Ar property Ns = Ns Ar value Oc Ns ...
2897 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
2899 Sets the property or list of properties to the given value(s) for each dataset.
2900 Only some properties can be edited.
2903 section for more information on what properties can be set and acceptable
2905 Numeric values can be specified as exact values, or in a human-readable form
2907 .Sy B , K , M , G , T , P , E , Z
2908 .Po for bytes, kilobytes, megabytes, gigabytes, terabytes, petabytes, exabytes,
2909 or zettabytes, respectively
2911 User properties can be set on snapshots.
2912 For more information, see the
2918 .Op Fl r Ns | Ns Fl d Ar depth
2920 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
2921 .Oo Fl s Ar source Ns Oo , Ns Ar source Oc Ns ... Oc
2922 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2923 .Cm all | Ar property Ns Oo , Ns Ar property Oc Ns ...
2924 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns | Ns Ar bookmark Ns ...
2926 Displays properties for the given datasets.
2927 If no datasets are specified, then the command displays properties for all
2928 datasets on the system.
2929 For each property, the following columns are displayed:
2932 property Property name
2933 value Property value
2934 source Property source. Can either be local, default,
2935 temporary, inherited, or none (-).
2938 All columns are displayed by default, though this can be controlled by using the
2941 This command takes a comma-separated list of properties as described in the
2942 .Sx Native Properties
2949 can be used to display all properties that apply to the given dataset's type
2950 .Pq filesystem, volume, snapshot, or bookmark .
2951 .Bl -tag -width "-H"
2953 Display output in a form more easily parsed by scripts.
2954 Any headers are omitted, and fields are explicitly separated by a single tab
2955 instead of an arbitrary amount of space.
2957 Recursively display any children of the dataset, limiting the recursion to
2961 will display only the dataset and its direct children.
2963 A comma-separated list of columns to display.
2964 .Sy name Ns \&, Ns Sy property Ns \&, Ns Sy value Ns \&, Ns Sy source
2965 is the default value.
2967 Display numbers in parsable
2971 Recursively display properties for any children.
2973 A comma-separated list of sources to display.
2974 Those properties coming from a source other than those in this list are ignored.
2975 Each source must be one of the following:
2982 The default value is all sources.
2984 A comma-separated list of types to display, where
2998 .Ar property Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
3000 Clears the specified property, causing it to be inherited from an ancestor,
3001 restored to default if no ancestor has the property set, or with the
3003 option reverted to the received value if one exists.
3006 section for a listing of default values, and details on which properties can be
3008 .Bl -tag -width "-r"
3010 Recursively inherit the given property for all children.
3012 Revert the property to the received value if one exists; otherwise operate as
3015 option was not specified.
3020 .Ar filesystem Ns | Ns Ar volume
3022 Remap the indirect blocks in the given fileystem or volume so that they no
3023 longer reference blocks on previously removed vdevs and we can eventually
3024 shrink the size of the indirect mapping objects for the previously removed
3025 vdevs. Note that remapping all blocks might not be possible and that
3026 references from snapshots will still exist and cannot be remapped.
3031 Displays a list of file systems that are not the most recent version.
3037 Displays a list of currently supported file system versions.
3043 .Fl a | Ar filesystem
3045 Upgrades file systems to a new on-disk version.
3046 Once this is done, the file systems will no longer be accessible on systems
3047 running older versions of the software.
3049 streams generated from new snapshots of these file systems cannot be accessed on
3050 systems running older versions of the software.
3052 In general, the file system version is independent of the pool version.
3055 for information on the
3056 .Nm zpool Cm upgrade
3059 In some cases, the file system version and the pool version are interrelated and
3060 the pool version must be upgraded before the file system version can be
3062 .Bl -tag -width "-V"
3064 Upgrade to the specified
3068 flag is not specified, this command upgrades to the most recent version.
3070 option can only be used to increase the version number, and only up to the most
3071 recent version supported by this software.
3073 Upgrade all file systems on all imported pools.
3075 Upgrade the specified file system.
3077 Upgrade the specified file system and all descendent file systems.
3083 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
3084 .Oo Fl s Ar field Oc Ns ...
3085 .Oo Fl S Ar field Oc Ns ...
3086 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
3087 .Ar filesystem Ns | Ns Ar snapshot
3089 Displays space consumed by, and quotas on, each user in the specified filesystem
3091 This corresponds to the
3092 .Sy userused@ Ns Em user ,
3093 .Sy userobjused@ Ns Em user ,
3094 .Sy userquota@ Ns Em user,
3096 .Sy userobjquota@ Ns Em user
3098 .Bl -tag -width "-H"
3100 Do not print headers, use tab-delimited output.
3102 Sort by this field in reverse order.
3106 Translate SID to POSIX ID.
3107 The POSIX ID may be ephemeral if no mapping exists.
3108 Normal POSIX interfaces
3113 perform this translation, so the
3115 option allows the output from
3116 .Nm zfs Cm userspace
3117 to be compared directly with those utilities.
3120 may lead to confusion if some files were created by an SMB user before a
3121 SMB-to-POSIX name mapping was established.
3122 In such a case, some files will be owned by the SMB entity and some by the POSIX
3126 option will report that the POSIX entity has the total usage and quota for both.
3128 Print numeric ID instead of user/group name.
3129 .It Fl o Ar field Ns Oo , Ns Ar field Oc Ns ...
3130 Display only the specified fields from the following set:
3135 The default is to display all fields.
3141 Sort output by this field.
3146 flags may be specified multiple times to sort first by one field, then by
3149 .Fl s Sy type Fl s Sy name .
3150 .It Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
3151 Print only the specified types from the following set:
3158 .Fl t Sy posixuser Ns \&, Ns Sy smbuser .
3159 The default can be changed to include group types.
3165 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
3166 .Oo Fl s Ar field Oc Ns ...
3167 .Oo Fl S Ar field Oc Ns ...
3168 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
3169 .Ar filesystem Ns | Ns Ar snapshot
3171 Displays space consumed by, and quotas on, each group in the specified
3172 filesystem or snapshot.
3173 This subcommand is identical to
3174 .Nm zfs Cm userspace ,
3175 except that the default types to display are
3176 .Fl t Sy posixgroup Ns \&, Ns Sy smbgroup .
3181 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
3182 .Oo Fl s Ar field Oc Ns ...
3183 .Oo Fl S Ar field Oc Ns ...
3184 .Ar filesystem Ns | Ns Ar snapshot
3186 Displays space consumed by, and quotas on, each project in the specified
3187 filesystem or snapshot. This subcommand is identical to
3188 .Nm zfs Cm userspace ,
3189 except that the project identifier is numeral, not name. So need neither
3192 for SID to POSIX ID nor
3200 .Oo Fl d Ns | Ns Fl r Ns Oc
3201 .Ar file Ns | Ns Ar directory Ns ...
3203 List project identifier (ID) and inherit flag of file(s) or directories.
3204 .Bl -tag -width "-d"
3206 Show the directory project ID and inherit flag, not its childrens. It will
3207 overwrite the former specified
3211 Show on subdirectories recursively. It will overwrite the former specified
3220 .Ar file Ns | Ns Ar directory Ns ...
3222 Clear project inherit flag and/or ID on the file(s) or directories.
3223 .Bl -tag -width "-k"
3225 Keep the project ID unchanged. If not specified, the project ID will be reset
3228 Clear on subdirectories recursively.
3235 .Oo Fl d Ns | Ns Fl r Ns Oc
3237 .Ar file Ns | Ns Ar directory Ns ...
3239 Check project ID and inherit flag on the file(s) or directories, report the
3240 entries without project inherit flag or with different project IDs from the
3243 option) value or the target directory's project ID.
3244 .Bl -tag -width "-0"
3246 Print file name with a trailing NUL instead of newline (by default), like
3249 Check the directory project ID and inherit flag, not its childrens. It will
3250 overwrite the former specified
3254 Specify the referenced ID for comparing with the target file(s) or directories'
3255 project IDs. If not specified, the target (top) directory's project ID will be
3256 used as the referenced one.
3258 Check on subdirectories recursively. It will overwrite the former specified
3267 .Ar file Ns | Ns Ar directory Ns ...
3269 .Bl -tag -width "-p"
3270 Set project ID and/or inherit flag on the file(s) or directories.
3272 Set the file(s)' or directories' project ID with the given value.
3274 Set on subdirectories recursively.
3276 Set project inherit flag on the given file(s) or directories. It is usually used
3277 for setup tree quota on the directory target with
3279 option specified together. When setup tree quota, by default the directory's
3280 project ID will be set to all its descendants unless you specify the project
3289 Displays all ZFS file systems currently mounted.
3295 .Fl a | Ar filesystem
3297 Mounts ZFS file systems.
3298 .Bl -tag -width "-O"
3300 Perform an overlay mount.
3303 for more information.
3305 Mount all available ZFS file systems.
3306 Invoked automatically as part of the boot process.
3308 Mount the specified filesystem.
3310 An optional, comma-separated list of mount options to use temporarily for the
3311 duration of the mount.
3313 .Sx Temporary Mount Point Properties
3314 section for details.
3316 Load keys for encrypted filesystems as they are being mounted. This is
3317 equivalent to executing
3319 on each encryption root before mounting it. Note that if a filesystem has a
3323 this will cause the terminal to interactively block after asking for the key.
3325 Report mount progress.
3331 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
3333 Unmounts currently mounted ZFS file systems.
3334 .Bl -tag -width "-a"
3336 Unmount all available ZFS file systems.
3337 Invoked automatically as part of the shutdown process.
3338 .It Ar filesystem Ns | Ns Ar mountpoint
3339 Unmount the specified filesystem.
3340 The command can also be given a path to a ZFS file system mount point on the
3343 Forcefully unmount the file system, even if it is currently in use.
3348 .Fl a | Ar filesystem
3350 Shares available ZFS file systems.
3351 .Bl -tag -width "-a"
3353 Share all available ZFS file systems.
3354 Invoked automatically as part of the boot process.
3356 Share the specified filesystem according to the
3361 File systems are shared when the
3370 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
3372 Unshares currently shared ZFS file systems.
3373 .Bl -tag -width "-a"
3375 Unshare all available ZFS file systems.
3376 Invoked automatically as part of the shutdown process.
3377 .It Ar filesystem Ns | Ns Ar mountpoint
3378 Unshare the specified filesystem.
3379 The command can also be given a path to a ZFS file system shared on the system.
3384 .Ar snapshot bookmark
3386 Creates a bookmark of the given snapshot.
3387 Bookmarks mark the point in time when the snapshot was created, and can be used
3388 as the incremental source for a
3392 This feature must be enabled to be used.
3394 .Xr zpool-features 5
3395 for details on ZFS feature flags and the
3402 .Op Oo Fl I Ns | Ns Fl i Oc Ar snapshot
3405 Creates a stream representation of the second
3407 which is written to standard output.
3408 The output can be redirected to a file or to a different system
3409 .Po for example, using
3412 By default, a full stream is generated.
3413 .Bl -tag -width "-D"
3415 Generate a deduplicated stream.
3416 Blocks which would have been sent multiple times in the send stream will only be
3418 The receiving system must also support this feature to receive a deduplicated
3420 This flag can be used regardless of the dataset's
3422 property, but performance will be much better if the filesystem uses a
3423 dedup-capable checksum
3427 .It Fl I Ar snapshot
3428 Generate a stream package that sends all intermediary snapshots from the first
3429 snapshot to the second snapshot.
3433 .Fl i Em @a Em fs@b Ns \&; Fl i Em @b Em fs@c Ns \&; Fl i Em @c Em fs@d .
3434 The incremental source may be specified as with the
3437 .It Fl L, -large-block
3438 Generate a stream which may contain blocks larger than 128KB.
3439 This flag has no effect if the
3441 pool feature is disabled, or if the
3443 property of this filesystem has never been set above 128KB.
3444 The receiving system must have the
3446 pool feature enabled as well.
3448 .Xr zpool-features 5
3449 for details on ZFS feature flags and the
3453 Print machine-parsable verbose information about the stream package generated.
3454 .It Fl R, -replicate
3455 Generate a replication stream package, which will replicate the specified
3456 file system, and all descendent file systems, up to the named snapshot.
3457 When received, all properties, snapshots, descendent file systems, and clones
3464 flags are used in conjunction with the
3466 flag, an incremental replication stream is generated.
3467 The current values of properties, and current snapshot and file system names are
3468 set when the stream is received.
3471 flag is specified when this stream is received, snapshots and file systems that
3472 do not exist on the sending side are destroyed.
3474 Generate a more compact stream by using
3476 records for blocks which are stored more compactly on disk by the
3479 This flag has no effect if the
3481 feature is disabled.
3482 The receiving system must have the
3487 feature is active on the sending system, then the receiving system must have
3488 that feature enabled as well. Datasets that are sent with this flag may not be
3489 received as an encrypted dataset, since encrypted datasets cannot use the
3493 .Xr zpool-features 5
3494 for details on ZFS feature flags and the
3498 Sends only received property values whether or not they are overridden by local
3499 settings, but only if the dataset has ever been received. Use this option when
3502 to restore received properties backed up on the sent dataset and to avoid
3503 sending local settings that may have nothing to do with the source dataset,
3504 but only with how the data is backed up.
3505 .It Fl c, -compressed
3506 Generate a more compact stream by using compressed WRITE records for blocks
3507 which are compressed on disk and in memory
3510 property for details
3514 feature is active on the sending system, then the receiving system must have
3515 that feature enabled as well.
3518 feature is enabled on the sending system but the
3520 option is not supplied in conjunction with
3522 then the data will be decompressed before sending so it can be split into
3523 smaller block sizes.
3525 For encrypted datasets, send data exactly as it exists on disk. This allows
3526 backups to be taken even if encryption keys are not currently loaded. The
3527 backup may then be received on an untrusted machine since that machine will
3528 not have the encryption keys to read the protected data or alter it without
3529 being detected. Upon being received, the dataset will have the same encryption
3530 keys as it did on the send side, although the
3532 property will be defaulted to
3534 if not otherwise provided. For unencrypted datasets, this flag will be
3537 Note that if you do not use this flag for sending encrypted datasets, data will
3538 be sent unencrypted and may be re-encrypted with a different encryption key on
3539 the receiving system, which will disable the ability to do a raw send to that
3540 system for incrementals.
3541 .It Fl i Ar snapshot
3542 Generate an incremental stream from the first
3544 .Pq the incremental source
3547 .Pq the incremental target .
3548 The incremental source can be specified as the last component of the snapshot
3552 character and following
3554 and it is assumed to be from the same file system as the incremental target.
3556 If the destination is a clone, the source may be the origin snapshot, which must
3559 .Em pool/fs@origin ,
3567 Do not generate any actual send data.
3568 This is useful in conjunction with the
3572 flags to determine what data will be sent.
3573 In this case, the verbose output will be written to standard output
3574 .Po contrast with a non-dry-run, where the stream is written to standard output
3575 and the verbose output goes to standard error
3578 Include the dataset's properties in the stream.
3579 This flag is implicit when
3582 The receiving system must also support this feature. Sends of encrypted datasets
3585 when using this flag.
3587 Print verbose information about the stream package generated.
3588 This information includes a per-second report of how much data has been sent.
3590 The format of the stream is committed.
3591 You will be able to receive your streams on future versions of ZFS.
3597 .Op Fl i Ar snapshot Ns | Ns Ar bookmark
3598 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
3600 Generate a send stream, which may be of a filesystem, and may be incremental
3602 If the destination is a filesystem or volume, the pool must be read-only, or the
3603 filesystem must not be mounted.
3604 When the stream generated from a filesystem or volume is received, the default
3605 snapshot name will be
3607 .Bl -tag -width "-L"
3608 .It Fl L, -large-block
3609 Generate a stream which may contain blocks larger than 128KB.
3610 This flag has no effect if the
3612 pool feature is disabled, or if the
3614 property of this filesystem has never been set above 128KB.
3615 The receiving system must have the
3617 pool feature enabled as well.
3619 .Xr zpool-features 5
3620 for details on ZFS feature flags and the
3624 Print machine-parsable verbose information about the stream package generated.
3625 .It Fl c, -compressed
3626 Generate a more compact stream by using compressed WRITE records for blocks
3627 which are compressed on disk and in memory
3630 property for details
3634 feature is active on the sending system, then the receiving system must have
3635 that feature enabled as well.
3638 feature is enabled on the sending system but the
3640 option is not supplied in conjunction with
3642 then the data will be decompressed before sending so it can be split into
3643 smaller block sizes.
3645 For encrypted datasets, send data exactly as it exists on disk. This allows
3646 backups to be taken even if encryption keys are not currently loaded. The
3647 backup may then be received on an untrusted machine since that machine will
3648 not have the encryption keys to read the protected data or alter it without
3649 being detected. Upon being received, the dataset will have the same encryption
3650 keys as it did on the send side, although the
3652 property will be defaulted to
3654 if not otherwise provided. For unencrypted datasets, this flag will be
3657 Note that if you do not use this flag for sending encrypted datasets, data will
3658 be sent unencrypted and may be re-encrypted with a different encryption key on
3659 the receiving system, which will disable the ability to do a raw send to that
3660 system for incrementals.
3662 Generate a more compact stream by using
3664 records for blocks which are stored more compactly on disk by the
3667 This flag has no effect if the
3669 feature is disabled.
3670 The receiving system must have the
3675 feature is active on the sending system, then the receiving system must have
3676 that feature enabled as well. Datasets that are sent with this flag may not be
3677 received as an encrypted dataset, since encrypted datasets cannot use the
3681 .Xr zpool-features 5
3682 for details on ZFS feature flags and the
3685 .It Fl i Ar snapshot Ns | Ns Ar bookmark
3686 Generate an incremental send stream.
3687 The incremental source must be an earlier snapshot in the destination's history.
3688 It will commonly be an earlier snapshot in the destination's file system, in
3689 which case it can be specified as the last component of the name
3694 character and following
3697 If the incremental target is a clone, the incremental source can be the origin
3698 snapshot, or an earlier snapshot in the origin's filesystem, or the origin's
3704 Do not generate any actual send data.
3705 This is useful in conjunction with the
3709 flags to determine what data will be sent.
3710 In this case, the verbose output will be written to standard output
3711 .Po contrast with a non-dry-run, where the stream is written to standard output
3712 and the verbose output goes to standard error
3715 Print verbose information about the stream package generated.
3716 This information includes a per-second report of how much data has been sent.
3723 .Ar receive_resume_token
3725 Creates a send stream which resumes an interrupted receive.
3727 .Ar receive_resume_token
3728 is the value of this property on the filesystem or volume that was being
3730 See the documentation for
3737 .Op Fl o Sy origin Ns = Ns Ar snapshot
3738 .Op Fl o Ar property Ns = Ns Ar value
3739 .Op Fl x Ar property
3740 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
3746 .Op Fl d Ns | Ns Fl e
3747 .Op Fl o Sy origin Ns = Ns Ar snapshot
3748 .Op Fl o Ar property Ns = Ns Ar value
3749 .Op Fl x Ar property
3752 Creates a snapshot whose contents are as specified in the stream provided on
3754 If a full stream is received, then a new file system is created as well.
3755 Streams are created using the
3757 subcommand, which by default creates a full stream.
3759 can be used as an alias for
3762 If an incremental stream is received, then the destination file system must
3763 already exist, and its most recent snapshot must match the incremental stream's
3767 the destination device link is destroyed and recreated, which means the
3769 cannot be accessed during the
3773 When a snapshot replication package stream that is generated by using the
3774 .Nm zfs Cm send Fl R
3775 command is received, any snapshots that do not exist on the sending location are
3776 destroyed by using the
3777 .Nm zfs Cm destroy Fl d
3781 .Fl o Em property Ns = Ns Ar value
3784 is specified, it applies to the effective value of the property throughout
3785 the entire subtree of replicated datasets. Effective property values will be
3790 ) on the topmost in the replicated subtree. In descendant datasets, if the
3791 property is set by the send stream, it will be overridden by forcing the
3792 property to be inherited from the top‐most file system. Received properties
3793 are retained in spite of being overridden and may be restored with
3794 .Nm zfs Cm inherit Fl S .
3796 .Fl o Sy origin Ns = Ns Em snapshot
3797 is a special case because, even if
3799 is a read-only property and cannot be set, it's allowed to receive the send
3800 stream as a clone of the given snapshot.
3802 Raw encrypted send streams (created with
3803 .Nm zfs Cm send Fl w
3804 ) may only be received as is, and cannot be re-encrypted, decrypted, or
3805 recompressed by the receive process. Unencrypted streams can be received as
3806 encrypted datasets, either through inheritance or by specifying encryption
3811 The name of the snapshot
3812 .Pq and file system, if a full stream is received
3813 that this subcommand creates depends on the argument type and the use of the
3819 If the argument is a snapshot name, the specified
3822 If the argument is a file system or volume name, a snapshot with the same name
3823 as the sent snapshot is created within the specified
3831 options are specified, the provided target snapshot name is used exactly as
3838 options cause the file system name of the target snapshot to be determined by
3839 appending a portion of the sent snapshot's name to the specified target
3843 option is specified, all but the first element of the sent snapshot's file
3845 .Pq usually the pool name
3846 is used and any required intermediate file systems within the specified one are
3850 option is specified, then only the last element of the sent snapshot's file
3852 .Pq i.e. the name of the source file system itself
3853 is used as the target file system name.
3854 .Bl -tag -width "-F"
3856 Force a rollback of the file system to the most recent snapshot before
3857 performing the receive operation.
3858 If receiving an incremental replication stream
3859 .Po for example, one generated by
3860 .Nm zfs Cm send Fl R Op Fl i Ns | Ns Fl I
3862 destroy snapshots and file systems that do not exist on the sending side.
3864 Discard the first element of the sent snapshot's file system name, using the
3865 remaining elements to determine the name of the target file system for the new
3866 snapshot as described in the paragraph above.
3868 Discard all but the last element of the sent snapshot's file system name, using
3869 that element to determine the name of the target file system for the new
3870 snapshot as described in the paragraph above.
3872 Do not actually receive the stream.
3873 This can be useful in conjunction with the
3875 option to verify the name the receive operation would use.
3876 .It Fl o Sy origin Ns = Ns Ar snapshot
3877 Forces the stream to be received as a clone of the given snapshot.
3878 If the stream is a full send stream, this will create the filesystem
3879 described by the stream as a clone of the specified snapshot.
3880 Which snapshot was specified will not affect the success or failure of the
3881 receive, as long as the snapshot does exist.
3882 If the stream is an incremental send stream, all the normal verification will be
3884 .It Fl o Em property Ns = Ns Ar value
3885 Sets the specified property as if the command
3886 .Nm zfs Cm set Em property Ns = Ns Ar value
3887 was invoked immediately before the receive. When receiving a stream from
3888 .Nm zfs Cm send Fl R ,
3889 causes the property to be inherited by all descendant datasets, as through
3890 .Nm zfs Cm inherit Em property
3891 was run on any descendant datasets that have this property set on the
3894 Any editable property can be set at receive time. Set-once properties bound
3895 to the received data, such as
3898 .Sy casesensitivity ,
3899 cannot be set at receive time even when the datasets are newly created by
3900 .Nm zfs Cm receive .
3901 Additionally both settable properties
3905 cannot be set at receive time.
3909 option may be specified multiple times, for different properties. An error
3910 results if the same property is specified in multiple
3916 If the receive is interrupted, save the partially received state, rather
3918 Interruption may be due to premature termination of the stream
3919 .Po e.g. due to network failure or failure of the remote system
3920 if the stream is being read over a network connection
3922 a checksum error in the stream, termination of the
3924 process, or unclean shutdown of the system.
3926 The receive can be resumed with a stream generated by
3927 .Nm zfs Cm send Fl t Ar token ,
3931 .Sy receive_resume_token
3932 property of the filesystem or volume which is received into.
3934 To use this flag, the storage pool must have the
3935 .Sy extensible_dataset
3938 .Xr zpool-features 5
3939 for details on ZFS feature flags.
3941 File system that is associated with the received stream is not mounted.
3943 Print verbose information about the stream and the time required to perform the
3945 .It Fl x Em property
3946 Ensures that the effective value of the specified property after the
3947 receive is unaffected by the value of that property in the send stream (if any),
3948 as if the property had been excluded from the send stream.
3950 If the specified property is not present in the send stream, this option does
3953 If a received property needs to be overridden, the effective value will be
3954 set or inherited, depending on whether the property is inheritable or not.
3956 In the case of an incremental update,
3958 leaves any existing local setting or explicit inheritance unchanged.
3962 restrictions on set-once and special properties apply equally to
3969 .Ar filesystem Ns | Ns Ar volume
3971 Abort an interrupted
3972 .Nm zfs Cm receive Fl s ,
3973 deleting its saved partially received state.
3977 .Ar filesystem Ns | Ns Ar volume
3979 Displays permissions that have been delegated on the specified filesystem or
3981 See the other forms of
3983 for more information.
3985 Delegations are supported under Linux with the exception of
3993 These permissions cannot be delegated because the Linux
3995 command restricts modifications of the global namespace to the root user.
4000 .Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
4001 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
4002 .Ar setname Oc Ns ...
4003 .Ar filesystem Ns | Ns Ar volume
4008 .Fl e Ns | Ns Sy everyone
4009 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
4010 .Ar setname Oc Ns ...
4011 .Ar filesystem Ns | Ns Ar volume
4013 Delegates ZFS administration permission for the file systems to non-privileged
4015 .Bl -tag -width "-d"
4017 Allow only for the descendent file systems.
4018 .It Fl e Ns | Ns Sy everyone
4019 Specifies that the permissions be delegated to everyone.
4020 .It Fl g Ar group Ns Oo , Ns Ar group Oc Ns ...
4021 Explicitly specify that permissions are delegated to the group.
4025 only for the specified file system.
4026 .It Fl u Ar user Ns Oo , Ns Ar user Oc Ns ...
4027 Explicitly specify that permissions are delegated to the user.
4028 .It Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
4029 Specifies to whom the permissions are delegated.
4030 Multiple entities can be specified as a comma-separated list.
4033 options are specified, then the argument is interpreted preferentially as the
4036 then as a user name, and lastly as a group name.
4037 To specify a user or group named
4044 To specify a group with the same name as a user, use the
4048 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
4049 .Ar setname Oc Ns ...
4051 The permissions to delegate.
4052 Multiple permissions may be specified as a comma-separated list.
4053 Permission names are the same as ZFS subcommand and property names.
4054 See the property list below.
4055 Property set names, which begin with
4060 form below for details.
4065 options are specified, or both are, then the permissions are allowed for the
4066 file system or volume, and all of its descendents.
4068 Permissions are generally the ability to use a ZFS subcommand or change a ZFS
4070 The following permissions are available:
4073 allow subcommand Must also have the permission that is
4075 clone subcommand Must also have the 'create' ability and
4076 'mount' ability in the origin file system
4077 create subcommand Must also have the 'mount' ability
4078 destroy subcommand Must also have the 'mount' ability
4079 diff subcommand Allows lookup of paths within a dataset
4080 given an object number, and the ability
4081 to create snapshots necessary to
4083 load-key subcommand Allows loading and unloading of encryption key
4084 (see 'zfs load-key' and 'zfs unload-key').
4085 change-key subcommand Allows changing an encryption key via
4087 mount subcommand Allows mount/umount of ZFS datasets
4088 promote subcommand Must also have the 'mount' and 'promote'
4089 ability in the origin file system
4090 receive subcommand Must also have the 'mount' and 'create'
4092 rename subcommand Must also have the 'mount' and 'create'
4093 ability in the new parent
4094 rollback subcommand Must also have the 'mount' ability
4096 share subcommand Allows sharing file systems over NFS
4098 snapshot subcommand Must also have the 'mount' ability
4100 groupquota other Allows accessing any groupquota@...
4102 groupused other Allows reading any groupused@... property
4103 userprop other Allows changing any user property
4104 userquota other Allows accessing any userquota@...
4106 userused other Allows reading any userused@... property
4107 projectobjquota other Allows accessing any projectobjquota@...
4109 projectquota other Allows accessing any projectquota@... property
4110 projectobjused other Allows reading any projectobjused@... property
4111 projectused other Allows reading any projectused@... property
4117 casesensitivity property
4119 compression property
4123 filesystem_limit property
4126 normalization property
4127 primarycache property
4132 refreservation property
4133 reservation property
4134 secondarycache property
4139 snapshot_limit property
4142 volblocksize property
4152 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
4153 .Ar setname Oc Ns ...
4154 .Ar filesystem Ns | Ns Ar volume
4159 These permissions are granted
4161 to the creator of any newly-created descendent file system.
4165 .Fl s No @ Ns Ar setname
4166 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
4167 .Ar setname Oc Ns ...
4168 .Ar filesystem Ns | Ns Ar volume
4170 Defines or adds permissions to a permission set.
4171 The set can be used by other
4173 commands for the specified file system and its descendents.
4174 Sets are evaluated dynamically, so changes to a set are immediately reflected.
4175 Permission sets follow the same naming restrictions as ZFS file systems, but the
4176 name must begin with
4178 and can be no more than 64 characters long.
4183 .Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
4184 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
4185 .Ar setname Oc Ns ... Oc
4186 .Ar filesystem Ns | Ns Ar volume
4191 .Fl e Ns | Ns Sy everyone
4192 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
4193 .Ar setname Oc Ns ... Oc
4194 .Ar filesystem Ns | Ns Ar volume
4200 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
4201 .Ar setname Oc Ns ... Oc
4202 .Ar filesystem Ns | Ns Ar volume
4204 Removes permissions that were granted with the
4207 No permissions are explicitly denied, so other permissions granted are still in
4209 For example, if the permission is granted by an ancestor.
4210 If no permissions are specified, then all permissions for the specified
4222 only removes the permissions that were granted to everyone, not all permissions
4223 for every user and group.
4226 command for a description of the
4229 .Bl -tag -width "-r"
4231 Recursively remove the permissions from this file system and all descendents.
4237 .Fl s No @ Ns Ar setname
4238 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
4239 .Ar setname Oc Ns ... Oc
4240 .Ar filesystem Ns | Ns Ar volume
4242 Removes permissions from a permission set.
4243 If no permissions are specified, then all permissions are removed, thus removing
4249 .Ar tag Ar snapshot Ns ...
4251 Adds a single reference, named with the
4253 argument, to the specified snapshot or snapshots.
4254 Each snapshot has its own tag namespace, and tags must be unique within that
4257 If a hold exists on a snapshot, attempts to destroy that snapshot by using the
4261 .Bl -tag -width "-r"
4263 Specifies that a hold with the given tag is applied recursively to the snapshots
4264 of all descendent file systems.
4272 Lists all existing user references for the given snapshot or snapshots.
4273 .Bl -tag -width "-r"
4275 Lists the holds that are set on the named descendent snapshots, in addition to
4276 listing the holds on the named snapshot.
4282 .Ar tag Ar snapshot Ns ...
4284 Removes a single reference, named with the
4286 argument, from the specified snapshot or snapshots.
4287 The tag must already exist for each snapshot.
4288 If a hold exists on a snapshot, attempts to destroy that snapshot by using the
4292 .Bl -tag -width "-r"
4294 Recursively releases a hold with the given tag on the snapshots of all
4295 descendent file systems.
4301 .Ar snapshot Ar snapshot Ns | Ns Ar filesystem
4303 Display the difference between a snapshot of a given filesystem and another
4304 snapshot of that filesystem from a later time or the current contents of the
4306 The first column is a character indicating the type of change, the other columns
4307 indicate pathname, new pathname
4308 .Pq in case of rename ,
4309 change in link count, and optionally file type and/or change time.
4310 The types of change are:
4312 - The path has been removed
4313 + The path has been created
4314 M The path has been modified
4315 R The path has been renamed
4317 .Bl -tag -width "-F"
4319 Display an indication of the type of file, in a manner similar to the
4335 Give more parsable tab-separated output, without header lines and without
4338 Display the path's inode change time as the first column of output.
4345 .Op Fl m Ar memory_limit
4351 as a ZFS channel program on
4354 program interface allows ZFS administrative operations to be run
4355 programmatically via a Lua script.
4356 The entire script is executed atomically, with no other administrative
4357 operations taking effect concurrently.
4358 A library of ZFS calls is made available to channel program scripts.
4359 Channel programs may only be run with root privileges.
4361 For full documentation of the ZFS channel program interface, see the manual
4366 Display channel program output in JSON format. When this flag is specified and
4367 standard output is empty - channel program encountered an error. The details of
4368 such an error will be printed to standard error in plain text.
4370 Executes a read-only channel program, which runs faster.
4371 The program cannot change on-disk state by calling functions from
4372 the zfs.sync submodule.
4373 The program can be used to gather information such as properties and
4374 determining if changes would succeed (zfs.check.*).
4375 Without this flag, all pending changes must be synced to disk before
4376 a channel program can complete.
4378 Execution time limit, in milliseconds.
4379 If a channel program executes for longer than the provided timeout, it will
4380 be stopped and an error will be returned.
4381 The default timeout is 1000 ms, and can be set to a maximum of 10000 ms.
4382 .It Fl m Ar memory-limit
4383 Memory limit, in bytes.
4384 If a channel program attempts to allocate more memory than the given limit,
4385 it will be stopped and an error returned.
4386 The default memory limit is 10 MB, and can be set to a maximum of 100 MB.
4388 All remaining argument strings are passed directly to the channel program as
4392 for more information.
4398 .Op Fl L Ar keylocation
4399 .Fl a | Ar filesystem
4403 allowing it and all children that inherit the
4405 property to be accessed. The key will be expected in the format specified by the
4407 and location specified by the
4409 property. Note that if the
4413 the terminal will interactively wait for the key to be entered. Loading a key
4414 will not automatically mount the dataset. If that functionality is desired,
4415 .Nm zfs Cm mount Sy -l
4416 will ask for the key and mount the dataset. Once the key is loaded the
4418 property will become
4420 .Bl -tag -width "-r"
4422 Recursively loads the keys for the specified filesystem and all descendent
4425 Loads the keys for all encryption roots in all imported pools.
4429 load-key. This will cause zfs to simply check that the
4430 provided key is correct. This command may be run even if the key is already
4432 .It Fl L Ar keylocation
4437 property. This will not change the value of the property on the dataset. Note
4438 that if used with either
4443 may only be given as
4450 .Fl a | Ar filesystem
4452 Unloads a key from ZFS, removing the ability to access the dataset and all of
4453 its children that inherit the
4455 property. This requires that the dataset is not currently open or mounted. Once
4456 the key is unloaded the
4458 property will become
4460 .Bl -tag -width "-r"
4462 Recursively unloads the keys for the specified filesystem and all descendent
4465 Unloads the keys for all encryption roots in all imported pools.
4471 .Op Fl o Ar keylocation Ns = Ns Ar value
4472 .Op Fl o Ar keyformat Ns = Ns Ar value
4473 .Op Fl o Ar pbkdf2iters Ns = Ns Ar value
4483 Allows a user to change the encryption key used to access a dataset. This
4484 command requires that the existing key for the dataset is already loaded into
4485 ZFS. This command may also be used to change the
4490 properties as needed. If the dataset was not previously an encryption root it
4491 will become one. Alternatively, the
4493 flag may be provided to cause an encryption root to inherit the parent's key
4495 .Bl -tag -width "-r"
4497 Ensures the key is loaded before attempting to change the key. This is
4498 effectively equivalent to
4499 .Qq Nm zfs Cm load-key Ar filesystem ; Nm zfs Cm change-key Ar filesystem
4500 .It Fl o Ar property Ns = Ns Ar value
4501 Allows the user to set encryption key properties (
4506 ) while changing the key. This is the only way to alter
4510 after the dataset has been created.
4512 Indicates that zfs should make
4514 inherit the key of its parent. Note that this command can only be run on an
4515 encryption root that has an encrypted parent.
4521 utility exits 0 on success, 1 if an error occurs, and 2 if invalid command line
4522 options were specified.
4525 .It Sy Example 1 No Creating a ZFS File System Hierarchy
4526 The following commands create a file system named
4528 and a file system named
4532 is set for the parent file system, and is automatically inherited by the child
4535 # zfs create pool/home
4536 # zfs set mountpoint=/export/home pool/home
4537 # zfs create pool/home/bob
4539 .It Sy Example 2 No Creating a ZFS Snapshot
4540 The following command creates a snapshot named
4542 This snapshot is mounted on demand in the
4544 directory at the root of the
4548 # zfs snapshot pool/home/bob@yesterday
4550 .It Sy Example 3 No Creating and Destroying Multiple Snapshots
4551 The following command creates snapshots named
4555 and all of its descendent file systems.
4556 Each snapshot is mounted on demand in the
4558 directory at the root of its file system.
4559 The second command destroys the newly created snapshots.
4561 # zfs snapshot -r pool/home@yesterday
4562 # zfs destroy -r pool/home@yesterday
4564 .It Sy Example 4 No Disabling and Enabling File System Compression
4565 The following command disables the
4567 property for all file systems under
4569 The next command explicitly enables
4572 .Em pool/home/anne .
4574 # zfs set compression=off pool/home
4575 # zfs set compression=on pool/home/anne
4577 .It Sy Example 5 No Listing ZFS Datasets
4578 The following command lists all active file systems and volumes in the system.
4579 Snapshots are displayed if the
4587 for more information on pool properties.
4590 NAME USED AVAIL REFER MOUNTPOINT
4591 pool 450K 457G 18K /pool
4592 pool/home 315K 457G 21K /export/home
4593 pool/home/anne 18K 457G 18K /export/home/anne
4594 pool/home/bob 276K 457G 276K /export/home/bob
4596 .It Sy Example 6 No Setting a Quota on a ZFS File System
4597 The following command sets a quota of 50 Gbytes for
4600 # zfs set quota=50G pool/home/bob
4602 .It Sy Example 7 No Listing ZFS Properties
4603 The following command lists all properties for
4606 # zfs get all pool/home/bob
4607 NAME PROPERTY VALUE SOURCE
4608 pool/home/bob type filesystem -
4609 pool/home/bob creation Tue Jul 21 15:53 2009 -
4610 pool/home/bob used 21K -
4611 pool/home/bob available 20.0G -
4612 pool/home/bob referenced 21K -
4613 pool/home/bob compressratio 1.00x -
4614 pool/home/bob mounted yes -
4615 pool/home/bob quota 20G local
4616 pool/home/bob reservation none default
4617 pool/home/bob recordsize 128K default
4618 pool/home/bob mountpoint /pool/home/bob default
4619 pool/home/bob sharenfs off default
4620 pool/home/bob checksum on default
4621 pool/home/bob compression on local
4622 pool/home/bob atime on default
4623 pool/home/bob devices on default
4624 pool/home/bob exec on default
4625 pool/home/bob setuid on default
4626 pool/home/bob readonly off default
4627 pool/home/bob zoned off default
4628 pool/home/bob snapdir hidden default
4629 pool/home/bob acltype off default
4630 pool/home/bob aclinherit restricted default
4631 pool/home/bob canmount on default
4632 pool/home/bob xattr on default
4633 pool/home/bob copies 1 default
4634 pool/home/bob version 4 -
4635 pool/home/bob utf8only off -
4636 pool/home/bob normalization none -
4637 pool/home/bob casesensitivity sensitive -
4638 pool/home/bob vscan off default
4639 pool/home/bob nbmand off default
4640 pool/home/bob sharesmb off default
4641 pool/home/bob refquota none default
4642 pool/home/bob refreservation none default
4643 pool/home/bob primarycache all default
4644 pool/home/bob secondarycache all default
4645 pool/home/bob usedbysnapshots 0 -
4646 pool/home/bob usedbydataset 21K -
4647 pool/home/bob usedbychildren 0 -
4648 pool/home/bob usedbyrefreservation 0 -
4651 The following command gets a single property value.
4653 # zfs get -H -o value compression pool/home/bob
4656 The following command lists all properties with local settings for
4659 # zfs get -r -s local -o name,property,value all pool/home/bob
4661 pool/home/bob quota 20G
4662 pool/home/bob compression on
4664 .It Sy Example 8 No Rolling Back a ZFS File System
4665 The following command reverts the contents of
4667 to the snapshot named
4669 deleting all intermediate snapshots.
4671 # zfs rollback -r pool/home/anne@yesterday
4673 .It Sy Example 9 No Creating a ZFS Clone
4674 The following command creates a writable file system whose initial contents are
4676 .Em pool/home/bob@yesterday .
4678 # zfs clone pool/home/bob@yesterday pool/clone
4680 .It Sy Example 10 No Promoting a ZFS Clone
4681 The following commands illustrate how to test out changes to a file system, and
4682 then replace the original file system with the changed one, using clones, clone
4683 promotion, and renaming:
4685 # zfs create pool/project/production
4686 populate /pool/project/production with data
4687 # zfs snapshot pool/project/production@today
4688 # zfs clone pool/project/production@today pool/project/beta
4689 make changes to /pool/project/beta and test them
4690 # zfs promote pool/project/beta
4691 # zfs rename pool/project/production pool/project/legacy
4692 # zfs rename pool/project/beta pool/project/production
4693 once the legacy version is no longer needed, it can be destroyed
4694 # zfs destroy pool/project/legacy
4696 .It Sy Example 11 No Inheriting ZFS Properties
4697 The following command causes
4703 property from their parent.
4705 # zfs inherit checksum pool/home/bob pool/home/anne
4707 .It Sy Example 12 No Remotely Replicating ZFS Data
4708 The following commands send a full stream and then an incremental stream to a
4709 remote machine, restoring them into
4710 .Em poolB/received/fs@a
4712 .Em poolB/received/fs@b ,
4715 must contain the file system
4716 .Em poolB/received ,
4717 and must not initially contain
4718 .Em poolB/received/fs .
4720 # zfs send pool/fs@a | \e
4721 ssh host zfs receive poolB/received/fs@a
4722 # zfs send -i a pool/fs@b | \e
4723 ssh host zfs receive poolB/received/fs
4725 .It Sy Example 13 No Using the zfs receive -d Option
4726 The following command sends a full stream of
4727 .Em poolA/fsA/fsB@snap
4728 to a remote machine, receiving it into
4729 .Em poolB/received/fsA/fsB@snap .
4732 portion of the received snapshot's name is determined from the name of the sent
4735 must contain the file system
4736 .Em poolB/received .
4738 .Em poolB/received/fsA
4739 does not exist, it is created as an empty file system.
4741 # zfs send poolA/fsA/fsB@snap | \e
4742 ssh host zfs receive -d poolB/received
4744 .It Sy Example 14 No Setting User Properties
4745 The following example sets the user-defined
4746 .Sy com.example:department
4747 property for a dataset.
4749 # zfs set com.example:department=12345 tank/accounting
4751 .It Sy Example 15 No Performing a Rolling Snapshot
4752 The following example shows how to maintain a history of snapshots with a
4753 consistent naming scheme.
4754 To keep a week's worth of snapshots, the user destroys the oldest snapshot,
4755 renames the remaining snapshots, and then creates a new snapshot, as follows:
4757 # zfs destroy -r pool/users@7daysago
4758 # zfs rename -r pool/users@6daysago @7daysago
4759 # zfs rename -r pool/users@5daysago @6daysago
4760 # zfs rename -r pool/users@yesterday @5daysago
4761 # zfs rename -r pool/users@yesterday @4daysago
4762 # zfs rename -r pool/users@yesterday @3daysago
4763 # zfs rename -r pool/users@yesterday @2daysago
4764 # zfs rename -r pool/users@today @yesterday
4765 # zfs snapshot -r pool/users@today
4767 .It Sy Example 16 No Setting sharenfs Property Options on a ZFS File System
4768 The following commands show how to set
4770 property options to enable
4774 addresses and to enable root access for system
4780 # zfs set sharenfs='rw=@123.123.0.0/16,root=neo' tank/home
4785 for host name resolution, specify the fully qualified hostname.
4786 .It Sy Example 17 No Delegating ZFS Administration Permissions on a ZFS Dataset
4787 The following example shows how to set permissions so that user
4789 can create, destroy, mount, and take snapshots on
4795 # zfs allow cindys create,destroy,mount,snapshot tank/cindys
4796 # zfs allow tank/cindys
4797 ---- Permissions on tank/cindys --------------------------------------
4798 Local+Descendent permissions:
4799 user cindys create,destroy,mount,snapshot
4804 mount point permission is set to 755 by default, user
4806 will be unable to mount file systems under
4808 Add an ACE similar to the following syntax to provide mount point access:
4810 # chmod A+user:cindys:add_subdirectory:allow /tank/cindys
4812 .It Sy Example 18 No Delegating Create Time Permissions on a ZFS Dataset
4813 The following example shows how to grant anyone in the group
4815 to create file systems in
4817 This syntax also allows staff members to destroy their own file systems, but not
4818 destroy anyone else's file system.
4823 # zfs allow staff create,mount tank/users
4824 # zfs allow -c destroy tank/users
4825 # zfs allow tank/users
4826 ---- Permissions on tank/users ---------------------------------------
4829 Local+Descendent permissions:
4830 group staff create,mount
4832 .It Sy Example 19 No Defining and Granting a Permission Set on a ZFS Dataset
4833 The following example shows how to define and grant a permission set on the
4840 # zfs allow -s @pset create,destroy,snapshot,mount tank/users
4841 # zfs allow staff @pset tank/users
4842 # zfs allow tank/users
4843 ---- Permissions on tank/users ---------------------------------------
4845 @pset create,destroy,mount,snapshot
4846 Local+Descendent permissions:
4849 .It Sy Example 20 No Delegating Property Permissions on a ZFS Dataset
4850 The following example shows to grant the ability to set quotas and reservations
4858 # zfs allow cindys quota,reservation users/home
4859 # zfs allow users/home
4860 ---- Permissions on users/home ---------------------------------------
4861 Local+Descendent permissions:
4862 user cindys quota,reservation
4863 cindys% zfs set quota=10G users/home/marks
4864 cindys% zfs get quota users/home/marks
4865 NAME PROPERTY VALUE SOURCE
4866 users/home/marks quota 10G local
4868 .It Sy Example 21 No Removing ZFS Delegated Permissions on a ZFS Dataset
4869 The following example shows how to remove the snapshot permission from the
4878 # zfs unallow staff snapshot tank/users
4879 # zfs allow tank/users
4880 ---- Permissions on tank/users ---------------------------------------
4882 @pset create,destroy,mount,snapshot
4883 Local+Descendent permissions:
4886 .It Sy Example 22 No Showing the differences between a snapshot and a ZFS Dataset
4887 The following example shows how to see what has changed between a prior
4888 snapshot of a ZFS dataset and its current state.
4891 option is used to indicate type information for the files affected.
4893 # zfs diff -F tank/test@before tank/test
4895 M F /tank/test/linked (+1)
4896 R F /tank/test/oldname -> /tank/test/newname
4897 - F /tank/test/deleted
4898 + F /tank/test/created
4899 M F /tank/test/modified
4901 .It Sy Example 23 No Creating a bookmark
4902 The following example create a bookmark to a snapshot. This bookmark
4903 can then be used instead of snapshot in send streams.
4905 # zfs bookmark rpool@snapshot rpool#bookmark
4907 .It Sy Example 24 No Setting sharesmb Property Options on a ZFS File System
4908 The following example show how to share SMB filesystem through ZFS. Note that
4909 that a user and his/her password must be given.
4911 # smbmount //127.0.0.1/share_tmp /mnt/tmp \\
4912 -o user=workgroup/turbo,password=obrut,uid=1000
4916 .Em /etc/samba/smb.conf
4917 configuration required:
4919 Samba will need to listen to 'localhost' (127.0.0.1) for the ZFS utilities to
4920 communicate with Samba. This is the default behavior for most Linux
4923 Samba must be able to authenticate a user. This can be done in a number of
4924 ways, depending on if using the system password file, LDAP or the Samba
4925 specific smbpasswd file. How to do this is outside the scope of this manual.
4928 man page for more information.
4931 .Sy USERSHARE section
4934 man page for all configuration options in case you need to modify any options
4935 to the share afterwards. Do note that any changes done with the
4937 command will be undone if the share is ever unshared (such as at a reboot etc).
4939 .Sh INTERFACE STABILITY
projects / zfs / blob