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37 .Nd configures ZFS file systems
44 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
50 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
51 .Fl V Ar size Ar volume
55 .Ar filesystem Ns | Ns Ar volume
59 .Ar filesystem Ns | Ns Ar volume Ns @ Ns Ar snap Ns
60 .Oo % Ns Ar snap Ns Oo , Ns Ar snap Ns Oo % Ns Ar snap Oc Oc Oc Ns ...
63 .Ar filesystem Ns | Ns Ar volume Ns # Ns Ar bookmark
67 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
68 .Ar filesystem Ns @ Ns Ar snapname Ns | Ns Ar volume Ns @ Ns Ar snapname Ns ...
76 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
77 .Ar snapshot Ar filesystem Ns | Ns Ar volume
84 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
85 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
89 .Ar filesystem Ns | Ns Ar volume
90 .Ar filesystem Ns | Ns Ar volume
94 .Ar snapshot Ar snapshot
97 .Op Fl r Ns | Ns Fl d Ar depth
99 .Oo Fl o Ar property Ns Oo , Ns Ar property Oc Ns ... Oc
100 .Oo Fl s Ar property Oc Ns ...
101 .Oo Fl S Ar property Oc Ns ...
102 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
103 .Oo Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Oc Ns ...
106 .Ar property Ns = Ns Ar value Oo Ar property Ns = Ns Ar value Oc Ns ...
107 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
110 .Op Fl r Ns | Ns Fl d Ar depth
112 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
113 .Oo Fl s Ar source Ns Oo , Ns Ar source Oc Ns ... Oc
114 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
115 .Cm all | Ar property Ns Oo , Ns Ar property Oc Ns ...
116 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns | Ns Ar bookmark Ns ...
120 .Ar property Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
130 .Fl a | Ar filesystem
134 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
135 .Oo Fl s Ar field Oc Ns ...
136 .Oo Fl S Ar field Oc Ns ...
137 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
138 .Ar filesystem Ns | Ns Ar snapshot
142 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
143 .Oo Fl s Ar field Oc Ns ...
144 .Oo Fl S Ar field Oc Ns ...
145 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
146 .Ar filesystem Ns | Ns Ar snapshot
153 .Fl a | Ar filesystem
157 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
160 .Fl a | Ar filesystem
163 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
166 .Ar snapshot bookmark
170 .Op Oo Fl I Ns | Ns Fl i Oc Ar snapshot
175 .Op Fl i Ar snapshot Ns | Ns Ar bookmark
176 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
180 .Fl t Ar receive_resume_token
184 .Op Fl o Sy origin Ns = Ns Ar snapshot
185 .Op Fl o Ar property Ns = Ns Ar value
187 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
191 .Op Fl d Ns | Ns Fl e
192 .Op Fl o Sy origin Ns = Ns Ar snapshot
193 .Op Fl o Ar property Ns = Ns Ar value
199 .Ar filesystem Ns | Ns Ar volume
202 .Ar filesystem Ns | Ns Ar volume
206 .Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
207 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
208 .Ar setname Oc Ns ...
209 .Ar filesystem Ns | Ns Ar volume
213 .Fl e Ns | Ns Sy everyone
214 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
215 .Ar setname Oc Ns ...
216 .Ar filesystem Ns | Ns Ar volume
220 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
221 .Ar setname Oc Ns ...
222 .Ar filesystem Ns | Ns Ar volume
225 .Fl s No @ Ns Ar setname
226 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
227 .Ar setname Oc Ns ...
228 .Ar filesystem Ns | Ns Ar volume
232 .Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
233 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
234 .Ar setname Oc Ns ... Oc
235 .Ar filesystem Ns | Ns Ar volume
239 .Fl e Ns | Ns Sy everyone
240 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
241 .Ar setname Oc Ns ... Oc
242 .Ar filesystem Ns | Ns Ar volume
247 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
248 .Ar setname Oc Ns ... Oc
249 .Ar filesystem Ns | Ns Ar volume
253 .Fl s @ Ns Ar setname
254 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
255 .Ar setname Oc Ns ... Oc
256 .Ar filesystem Ns | Ns Ar volume
260 .Ar tag Ar snapshot Ns ...
268 .Ar tag Ar snapshot Ns ...
272 .Ar snapshot Ar snapshot Ns | Ns Ar filesystem
276 .Op Fl L Ar keylocation
277 .Fl a | Ar filesystem
281 .Fl a | Ar filesystem
285 .Op Fl o Ar keylocation Ns = Ns Ar value
286 .Op Fl o Ar keyformat Ns = Ns Ar value
287 .Op Fl o Ar pbkdf2iters Ns = Ns Ar value
297 command configures ZFS datasets within a ZFS storage pool, as described in
299 A dataset is identified by a unique path within the ZFS namespace.
302 pool/{filesystem,volume,snapshot}
305 where the maximum length of a dataset name is
309 A dataset can be one of the following:
310 .Bl -tag -width "file system"
312 A ZFS dataset of type
314 can be mounted within the standard system namespace and behaves like other file
316 While ZFS file systems are designed to be POSIX compliant, known issues exist
317 that prevent compliance in some cases.
318 Applications that depend on standards conformance might fail due to non-standard
319 behavior when checking file system free space.
321 A logical volume exported as a raw or block device.
322 This type of dataset should only be used under special circumstances.
323 File systems are typically used in most environments.
325 A read-only version of a file system or volume at a given point in time.
327 .Ar filesystem Ns @ Ns Ar name
329 .Ar volume Ns @ Ns Ar name .
333 but without the hold on on-disk data. It can be used as the source of a send
334 (but not for a receive). It is specified as
335 .Ar filesystem Ns # Ns Ar name
337 .Ar volume Ns # Ns Ar name .
339 .Ss ZFS File System Hierarchy
340 A ZFS storage pool is a logical collection of devices that provide space for
342 A storage pool is also the root of the ZFS file system hierarchy.
344 The root of the pool can be accessed as a file system, such as mounting and
345 unmounting, taking snapshots, and setting properties.
346 The physical storage characteristics, however, are managed by the
352 for more information on creating and administering pools.
354 A snapshot is a read-only copy of a file system or volume.
355 Snapshots can be created extremely quickly, and initially consume no additional
356 space within the pool.
357 As data within the active dataset changes, the snapshot consumes more data than
358 would otherwise be shared with the active dataset.
360 Snapshots can have arbitrary names.
361 Snapshots of volumes can be cloned or rolled back, visibility is determined
364 property of the parent volume.
366 File system snapshots can be accessed under the
368 directory in the root of the file system.
369 Snapshots are automatically mounted on demand and may be unmounted at regular
371 The visibility of the
373 directory can be controlled by the
377 A bookmark is like a snapshot, a read-only copy of a file system or volume.
378 Bookmarks can be created extremely quickly, compared to snapshots, and they
379 consume no additional space within the pool. Bookmarks can also have arbitrary
380 names, much like snapshots.
382 Unlike snapshots, bookmarks can not be accessed through the filesystem in any
383 way. From a storage standpoint a bookmark just provides a way to reference
384 when a snapshot was created as a distinct object. Bookmarks are initially
385 tied to a snapshot, not the filesystem or volume, and they will survive if the
386 snapshot itself is destroyed. Since they are very light weight there's little
387 incentive to destroy them.
389 A clone is a writable volume or file system whose initial contents are the same
391 As with snapshots, creating a clone is nearly instantaneous, and initially
392 consumes no additional space.
394 Clones can only be created from a snapshot.
395 When a snapshot is cloned, it creates an implicit dependency between the parent
397 Even though the clone is created somewhere else in the dataset hierarchy, the
398 original snapshot cannot be destroyed as long as a clone exists.
401 property exposes this dependency, and the
403 command lists any such dependencies, if they exist.
405 The clone parent-child dependency relationship can be reversed by using the
410 file system to become a clone of the specified file system, which makes it
411 possible to destroy the file system that the clone was created from.
413 Creating a ZFS file system is a simple operation, so the number of file systems
414 per system is likely to be numerous.
415 To cope with this, ZFS automatically manages mounting and unmounting file
416 systems without the need to edit the
419 All automatically managed file systems are mounted by ZFS at boot time.
421 By default, file systems are mounted under
425 is the name of the file system in the ZFS namespace.
426 Directories are created and destroyed as needed.
428 A file system can also have a mount point set in the
431 This directory is created as needed, and ZFS automatically mounts the file
433 .Nm zfs Cm mount Fl a
440 property can be inherited, so if
446 automatically inherits a mount point of
447 .Pa /export/stuff/user .
453 prevents the file system from being mounted.
455 If needed, ZFS file systems can also be managed with traditional tools
461 If a file system's mount point is set to
463 ZFS makes no attempt to manage the file system, and the administrator is
464 responsible for mounting and unmounting the file system. Because pools must
465 be imported before a legacy mount can succeed, administrators should ensure
466 that legacy mounts are only attempted after the zpool import process
467 finishes at boot time. For example, on machines using systemd, the mount
470 .Nm x-systemd.requires=zfs-import.target
472 will ensure that the zfs-import completes before systemd attempts mounting
473 the filesystem. See systemd.mount(5) for details.
475 Deduplication is the process for removing redundant data at the block level,
476 reducing the total amount of data stored. If a file system has the
478 property enabled, duplicate data blocks are removed synchronously. The result
479 is that only unique data is stored and common components are shared among files.
481 Deduplicating data is a very resource-intensive operation. It is generally
482 recommended that you have at least 1.25 GiB of RAM per 1 TiB of storage when
483 you enable deduplication. Calculating the exact requirement depends heavily
484 on the type of data stored in the pool.
486 Enabling deduplication on an improperly-designed system can result in
487 performance issues (slow IO and administrative operations). It can potentially
488 lead to problems importing a pool due to memory exhaustion. Deduplication
489 can consume significant processing power (CPU) and memory as well as generate
492 Before creating a pool with deduplication enabled, ensure that you have planned
493 your hardware requirements appropriately and implemented appropriate recovery
494 practices, such as regular backups. As an alternative to deduplication
497 as a less resource-intensive alternative.
498 .Ss Native Properties
499 Properties are divided into two types, native properties and user-defined
504 Native properties either export internal statistics or control ZFS behavior.
505 In addition, native properties are either editable or read-only.
506 User properties have no effect on ZFS behavior, but you can use them to annotate
507 datasets in a way that is meaningful in your environment.
508 For more information about user properties, see the
512 Every dataset has a set of properties that export statistics about the dataset
513 as well as control various behaviors.
514 Properties are inherited from the parent unless overridden by the child.
515 Some properties apply only to certain types of datasets
516 .Pq file systems, volumes, or snapshots .
518 The values of numeric properties can be specified using human-readable suffixes
528 The following are all valid
531 .Li 1536M, 1.5g, 1.50GB .
533 The values of non-numeric properties are case sensitive and must be lowercase,
540 The following native properties consist of read-only statistics about the
542 These properties can be neither set, nor inherited.
543 Native properties apply to all dataset types unless otherwise noted.
544 .Bl -tag -width "usedbyrefreservation"
546 The amount of space available to the dataset and all its children, assuming that
547 there is no other activity in the pool.
548 Because space is shared within a pool, availability can be limited by any number
549 of factors, including physical pool size, quotas, reservations, or other
550 datasets within the pool.
552 This property can also be referred to by its shortened column name,
555 For non-snapshots, the compression ratio achieved for the
557 space of this dataset, expressed as a multiplier.
560 property includes descendant datasets, and, for clones, does not include the
561 space shared with the origin snapshot.
567 Compression can be turned on by running:
568 .Nm zfs Cm set Sy compression Ns = Ns Sy on Ar dataset .
572 The transaction group (txg) in which the dataset was created. Bookmarks have
575 as the snapshot they are initially tied to. This property is suitable for
576 ordering a list of snapshots, e.g. for incremental send and receive.
578 The time this dataset was created.
580 For snapshots, this property is a comma-separated list of filesystems or volumes
581 which are clones of this snapshot.
584 property is this snapshot.
587 property is not empty, then this snapshot can not be destroyed
594 The roles of origin and clone can be swapped by promoting the clone with the
600 if the snapshot has been marked for deferred destroy by using the
601 .Nm zfs Cm destroy Fl d
603 Otherwise, the property is
605 .It Sy encryptionroot
606 For encrypted datasets, indicates where the dataset is currently inheriting its
607 encryption key from. Loading or unloading a key for the
609 will implicitly load / unload the key for any inheriting datasets (see
612 .Nm zfs Cm unload-key
614 Clones will always share an
615 encryption key with their origin. See the
618 .It Sy filesystem_count
619 The total number of filesystems and volumes that exist under this location in
621 This value is only available when a
623 has been set somewhere in the tree under which the dataset resides.
625 Indicates if an encryption key is currently loaded into ZFS. The possible
634 .Nm zfs Cm unload-key .
636 The 64 bit GUID of this dataset or bookmark which does not change over its
637 entire lifetime. When a snapshot is sent to another pool, the received
638 snapshot has the same GUID. Thus, the
640 is suitable to identify a snapshot across pools.
641 .It Sy logicalreferenced
642 The amount of space that is
644 accessible by this dataset.
648 The logical space ignores the effect of the
652 properties, giving a quantity closer to the amount of data that applications
654 However, it does include space consumed by metadata.
656 This property can also be referred to by its shortened column name,
659 The amount of space that is
661 consumed by this dataset and all its descendents.
665 The logical space ignores the effect of the
669 properties, giving a quantity closer to the amount of data that applications
671 However, it does include space consumed by metadata.
673 This property can also be referred to by its shortened column name,
676 For file systems, indicates whether the file system is currently mounted.
677 This property can be either
682 For cloned file systems or volumes, the snapshot from which the clone was
687 .It Sy receive_resume_token
688 For filesystems or volumes which have saved partially-completed state from
690 this opaque token can be provided to
692 to resume and complete the
695 The amount of data that is accessible by this dataset, which may or may not be
696 shared with other datasets in the pool.
697 When a snapshot or clone is created, it initially references the same amount of
698 space as the file system or snapshot it was created from, since its contents are
701 This property can also be referred to by its shortened column name,
703 .It Sy refcompressratio
704 The compression ratio achieved for the
706 space of this dataset, expressed as a multiplier.
710 .It Sy snapshot_count
711 The total number of snapshots that exist under this location in the dataset
713 This value is only available when a
715 has been set somewhere in the tree under which the dataset resides.
723 The amount of space consumed by this dataset and all its descendents.
724 This is the value that is checked against this dataset's quota and reservation.
725 The space used does not include this dataset's reservation, but does take into
726 account the reservations of any descendent datasets.
727 The amount of space that a dataset consumes from its parent, as well as the
728 amount of space that is freed if this dataset is recursively destroyed, is the
729 greater of its space used and its reservation.
731 The used space of a snapshot
736 is space that is referenced exclusively by this snapshot.
737 If this snapshot is destroyed, the amount of
740 Space that is shared by multiple snapshots isn't accounted for in this metric.
741 When a snapshot is destroyed, space that was previously shared with this
742 snapshot can become unique to snapshots adjacent to it, thus changing the used
743 space of those snapshots.
744 The used space of the latest snapshot can also be affected by changes in the
748 space of a snapshot is a subset of the
750 space of the snapshot.
752 The amount of space used, available, or referenced does not take into account
754 Pending changes are generally accounted for within a few seconds.
755 Committing a change to a disk using
759 does not necessarily guarantee that the space usage information is updated
764 properties decompose the
766 properties into the various reasons that space is used.
769 .Sy usedbychildren No +
770 .Sy usedbydataset No +
771 .Sy usedbyrefreservation No +
772 .Sy usedbysnapshots .
773 These properties are only available for datasets created on
777 .It Sy usedbychildren
778 The amount of space used by children of this dataset, which would be freed if
779 all the dataset's children were destroyed.
781 The amount of space used by this dataset itself, which would be freed if the
782 dataset were destroyed
783 .Po after first removing any
785 and destroying any necessary snapshots or descendents
787 .It Sy usedbyrefreservation
788 The amount of space used by a
790 set on this dataset, which would be freed if the
793 .It Sy usedbysnapshots
794 The amount of space consumed by snapshots of this dataset.
795 In particular, it is the amount of space that would be freed if all of this
796 dataset's snapshots were destroyed.
797 Note that this is not simply the sum of the snapshots'
799 properties because space can be shared by multiple snapshots.
800 .It Sy userused Ns @ Ns Em user
801 The amount of space consumed by the specified user in this dataset.
802 Space is charged to the owner of each file, as displayed by
804 The amount of space charged is displayed by
810 subcommand for more information.
812 Unprivileged users can access only their own space usage.
813 The root user, or a user who has been granted the
817 can access everyone's usage.
820 .Sy userused Ns @ Ns Em ...
821 properties are not displayed by
822 .Nm zfs Cm get Sy all .
823 The user's name must be appended after the @ symbol, using one of the following
825 .Bl -bullet -width ""
839 .Sy joe.smith@mydomain
848 Files created on Linux always have POSIX owners.
849 .It Sy userobjused Ns @ Ns Em user
852 property is similar to
854 but instead it counts the number of objects consumed by a user. This property
855 counts all objects allocated on behalf of the user, it may differ from the
856 results of system tools such as
861 is set on a file system additional objects will be created per-file to store
862 extended attributes. These additional objects are reflected in the
864 value and are counted against the user's
866 When a file system is configured to use
868 no additional internal objects are normally required.
870 This property is set to the number of user holds on this snapshot.
871 User holds are set by using the
874 .It Sy groupused Ns @ Ns Em group
875 The amount of space consumed by the specified group in this dataset.
876 Space is charged to the group of each file, as displayed by
879 .Sy userused Ns @ Ns Em user
880 property for more information.
882 Unprivileged users can only access their own groups' space usage.
883 The root user, or a user who has been granted the
887 can access all groups' usage.
888 .It Sy groupobjused Ns @ Ns Em group
889 The number of objects consumed by the specified group in this dataset.
890 Multiple objects may be charged to the group for each file when extended
891 attributes are in use. See the
892 .Sy userobjused Ns @ Ns Em user
893 property for more information.
895 Unprivileged users can only access their own groups' space usage.
896 The root user, or a user who has been granted the
900 can access all groups' usage.
902 For volumes, specifies the block size of the volume.
905 cannot be changed once the volume has been written, so it should be set at
906 volume creation time.
909 for volumes is 8 Kbytes.
910 Any power of 2 from 512 bytes to 128 Kbytes is valid.
912 This property can also be referred to by its shortened column name,
917 by this dataset, that was written since the previous snapshot
918 .Pq i.e. that is not referenced by the previous snapshot .
919 .It Sy written Ns @ Ns Em snapshot
922 space written to this dataset since the specified snapshot.
923 This is the space that is referenced by this dataset but was not referenced by
924 the specified snapshot.
928 may be specified as a short snapshot name
929 .Po just the part after the
932 in which case it will be interpreted as a snapshot in the same filesystem as
936 may be a full snapshot name
937 .Po Em filesystem Ns @ Ns Em snapshot Pc ,
938 which for clones may be a snapshot in the origin's filesystem
939 .Pq or the origin of the origin's filesystem, etc.
942 The following native properties can be used to change the behavior of a ZFS
946 .Sy aclinherit Ns = Ns Sy discard Ns | Ns Sy noallow Ns | Ns
947 .Sy restricted Ns | Ns Sy passthrough Ns | Ns Sy passthrough-x
949 Controls how ACEs are inherited when files and directories are created.
950 .Bl -tag -width "passthrough-x"
952 does not inherit any ACEs.
954 only inherits inheritable ACEs that specify
962 permissions when the ACE is inherited.
964 inherits all inheritable ACEs without any modifications.
973 ACEs inherit the execute permission only if the file creation mode also requests
977 When the property value is set to
979 files are created with a mode determined by the inheritable ACEs.
980 If no inheritable ACEs exist that affect the mode, then the mode is set in
981 accordance to the requested mode from the application.
985 property does not apply to posix ACLs.
986 .It Sy acltype Ns = Ns Sy off Ns | Ns Sy noacl Ns | Ns Sy posixacl
987 Controls whether ACLs are enabled and if so what type of ACL to use.
988 .Bl -tag -width "posixacl"
990 default, when a file system has the
992 property set to off then ACLs are disabled.
997 indicates posix ACLs should be used. Posix ACLs are specific to Linux and are
998 not functional on other platforms. Posix ACLs are stored as an extended
999 attribute and therefore will not overwrite any existing NFSv4 ACLs which
1003 To obtain the best performance when setting
1005 users are strongly encouraged to set the
1007 property. This will result in the posix ACL being stored more efficiently on
1008 disk. But as a consequence of this all new extended attributes will only be
1009 accessible from OpenZFS implementations which support the
1013 property for more details.
1014 .It Sy atime Ns = Ns Sy on Ns | Ns Sy off
1015 Controls whether the access time for files is updated when they are read.
1016 Turning this property off avoids producing write traffic when reading files and
1017 can result in significant performance gains, though it might confuse mailers
1018 and other similar utilities. The values
1022 are equivalent to the
1026 mount options. The default value is
1031 .It Sy canmount Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy noauto
1032 If this property is set to
1034 the file system cannot be mounted, and is ignored by
1035 .Nm zfs Cm mount Fl a .
1036 Setting this property to
1038 is similar to setting the
1042 except that the dataset still has a normal
1044 property, which can be inherited.
1045 Setting this property to
1047 allows datasets to be used solely as a mechanism to inherit properties.
1048 One example of setting
1049 .Sy canmount Ns = Ns Sy off
1050 is to have two datasets with the same
1052 so that the children of both datasets appear in the same directory, but might
1053 have different inherited characteristics.
1057 a dataset can only be mounted and unmounted explicitly.
1058 The dataset is not mounted automatically when the dataset is created or
1059 imported, nor is it mounted by the
1060 .Nm zfs Cm mount Fl a
1061 command or unmounted by the
1062 .Nm zfs Cm unmount Fl a
1065 This property is not inherited.
1067 .Sy checksum Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy fletcher2 Ns | Ns
1068 .Sy fletcher4 Ns | Ns Sy sha256 Ns | Ns Sy noparity Ns | Ns
1069 .Sy sha512 Ns | Ns Sy skein Ns | Ns Sy edonr
1071 Controls the checksum used to verify data integrity.
1072 The default value is
1074 which automatically selects an appropriate algorithm
1077 but this may change in future releases
1081 disables integrity checking on user data.
1084 not only disables integrity but also disables maintaining parity for user data.
1085 This setting is used internally by a dump device residing on a RAID-Z pool and
1086 should not be used by any other dataset.
1087 Disabling checksums is
1089 a recommended practice.
1096 checksum algorithms require enabling the appropriate features on the pool.
1098 .Xr zpool-features 5
1099 for more information on these algorithms.
1101 Changing this property affects only newly-written data.
1103 .Sy compression Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy gzip Ns | Ns
1104 .Sy gzip- Ns Em N Ns | Ns Sy lz4 Ns | Ns Sy lzjb Ns | Ns Sy zle
1106 Controls the compression algorithm used for this dataset.
1108 Setting compression to
1110 indicates that the current default compression algorithm should be used.
1111 The default balances compression and decompression speed, with compression ratio
1112 and is expected to work well on a wide variety of workloads.
1113 Unlike all other settings for this property,
1115 does not select a fixed compression type.
1116 As new compression algorithms are added to ZFS and enabled on a pool, the
1117 default compression algorithm may change.
1118 The current default compression algorithm is either
1127 compression algorithm is a high-performance replacement for the
1130 It features significantly faster compression and decompression, as well as a
1131 moderately higher compression ratio than
1133 but can only be used on pools with the
1138 .Xr zpool-features 5
1139 for details on ZFS feature flags and the
1145 compression algorithm is optimized for performance while providing decent data
1150 compression algorithm uses the same compression as the
1155 level by using the value
1159 is an integer from 1
1162 .Pq best compression ratio .
1167 .Po which is also the default for
1173 compression algorithm compresses runs of zeros.
1175 This property can also be referred to by its shortened column name
1177 Changing this property affects only newly-written data.
1179 .Sy context Ns = Ns Sy none Ns | Ns
1180 .Em SELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level
1182 This flag sets the SELinux context for all files in the file system under
1183 a mount point for that file system. See
1185 for more information.
1187 .Sy fscontext Ns = Ns Sy none Ns | Ns
1188 .Em SELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level
1190 This flag sets the SELinux context for the file system file system being
1193 for more information.
1195 .Sy defcontext Ns = Ns Sy none Ns | Ns
1196 .Em SELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level
1198 This flag sets the SELinux default context for unlabeled files. See
1200 for more information.
1202 .Sy rootcontext Ns = Ns Sy none Ns | Ns
1203 .Em SELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level
1205 This flag sets the SELinux context for the root inode of the file system. See
1207 for more information.
1208 .It Sy copies Ns = Ns Sy 1 Ns | Ns Sy 2 Ns | Ns Sy 3
1209 Controls the number of copies of data stored for this dataset.
1210 These copies are in addition to any redundancy provided by the pool, for
1211 example, mirroring or RAID-Z.
1212 The copies are stored on different disks, if possible.
1213 The space used by multiple copies is charged to the associated file and dataset,
1216 property and counting against quotas and reservations.
1218 Changing this property only affects newly-written data.
1219 Therefore, set this property at file system creation time by using the
1220 .Fl o Sy copies Ns = Ns Ar N
1223 Remember that ZFS will not import a pool with a missing top-level vdev. Do
1225 create, for example a two-disk striped pool and set
1227 on some datasets thinking you have setup redundancy for them. When a disk
1228 fails you will not be able to import the pool and will have lost all of your
1230 .It Sy devices Ns = Ns Sy on Ns | Ns Sy off
1231 Controls whether device nodes can be opened on this file system.
1232 The default value is
1238 are equivalent to the
1244 .Sy dnodesize Ns = Ns Sy legacy Ns | Ns Sy auto Ns | Ns Sy 1k Ns | Ns
1245 .Sy 2k Ns | Ns Sy 4k Ns | Ns Sy 8k Ns | Ns Sy 16k
1247 Specifies a compatibility mode or literal value for the size of dnodes in the
1248 file system. The default value is
1250 Setting this property to a value other than
1252 requires the large_dnode pool feature to be enabled.
1258 if the dataset uses the
1260 property setting and the workload makes heavy use of extended attributes. This
1261 may be applicable to SELinux-enabled systems, Lustre servers, and Samba
1262 servers, for example. Literal values are supported for cases where the optimal
1263 size is known in advance and for performance testing.
1269 if you need to receive a send stream of this dataset on a pool that doesn't
1270 enable the large_dnode feature, or if you need to import this pool on a system
1271 that doesn't support the large_dnode feature.
1273 This property can also be referred to by its shortened column name,
1276 .Sy encryption Ns = Ns Sy off Ns | Ns Sy on Ns | Ns Sy aes-128-ccm Ns | Ns
1277 .Sy aes-192-ccm Ns | Ns Sy aes-256-ccm Ns | Ns Sy aes-128-gcm Ns | Ns
1278 .Sy aes-192-gcm Ns | Ns Sy aes-256-gcm
1280 Controls the encryption cipher suite (block cipher, key length, and mode) used
1281 for this dataset. Requires the
1283 feature to be enabled on the pool.
1286 to be set at dataset creation time.
1289 .Sy encryption Ns = Ns Sy on
1290 when creating a dataset indicates that the default encryption suite will be
1291 selected, which is currently
1293 In order to provide consistent data protection, encryption must be specified at
1294 dataset creation time and it cannot be changed afterwards.
1296 For more details and caveats about encryption see the
1299 .It Sy keyformat Ns = Ns Sy raw Ns | Ns Sy hex Ns | Ns Sy passphrase
1300 Controls what format the user's encryption key will be provided as. This
1301 property is only set when the dataset is encrypted.
1303 Raw keys and hex keys must be 32 bytes long (regardless of the chosen
1304 encryption suite) and must be randomly generated. A raw key can be generated
1305 with the following command:
1307 # dd if=/dev/urandom of=/path/to/output/key bs=32 count=1
1310 Passphrases must be between 8 and 512 bytes long and will be processed through
1311 PBKDF2 before being used (see the
1313 property). Even though the
1314 encryption suite cannot be changed after dataset creation, the keyformat can be
1316 .Nm zfs Cm change-key .
1318 .Sy keylocation Ns = Ns Sy prompt Ns | Ns Sy file:// Ns Em </absolute/file/path>
1320 Controls where the user's encryption key will be loaded from by default for
1324 .Nm zfs Cm mount Cm -l . This property is
1325 only set for encrypted datasets which are encryption roots. If unspecified, the
1329 Even though the encryption suite cannot be changed after dataset creation, the
1330 keylocation can be with either
1333 .Nm zfs Cm change-key .
1336 is selected ZFS will ask for the key at the command prompt when it is required
1337 to access the encrypted data (see
1339 for details). This setting will also allow the key to be passed in via STDIN,
1340 but users should be careful not to place keys which should be kept secret on
1341 the command line. If a file URI is selected, the key will be loaded from the
1342 specified absolute file path.
1343 .It Sy pbkdf2iters Ns = Ns Ar iterations
1344 Controls the number of PBKDF2 iterations that a
1346 encryption key should be run through when processing it into an encryption key.
1347 This property is only defined when encryption is enabled and a keyformat of
1349 is selected. The goal of PBKDF2 is to significantly increase the
1350 computational difficulty needed to brute force a user's passphrase. This is
1351 accomplished by forcing the attacker to run each passphrase through a
1352 computationally expensive hashing function many times before they arrive at the
1353 resulting key. A user who actually knows the passphrase will only have to pay
1354 this cost once. As CPUs become better at processing, this number should be
1355 raised to ensure that a brute force attack is still not possible. The current
1360 This property may be changed with
1361 .Nm zfs Cm change-key .
1362 .It Sy exec Ns = Ns Sy on Ns | Ns Sy off
1363 Controls whether processes can be executed from within this file system.
1364 The default value is
1370 are equivalent to the
1375 .It Sy filesystem_limit Ns = Ns Em count Ns | Ns Sy none
1376 Limits the number of filesystems and volumes that can exist under this point in
1378 The limit is not enforced if the user is allowed to change the limit.
1380 .Sy filesystem_limit
1383 a descendent of a filesystem that already has a
1384 .Sy filesystem_limit
1385 does not override the ancestor's
1386 .Sy filesystem_limit ,
1387 but rather imposes an additional limit.
1388 This feature must be enabled to be used
1390 .Xr zpool-features 5
1392 .It Sy mountpoint Ns = Ns Pa path Ns | Ns Sy none Ns | Ns Sy legacy
1393 Controls the mount point used for this file system.
1396 section for more information on how this property is used.
1400 property is changed for a file system, the file system and any children that
1401 inherit the mount point are unmounted.
1404 then they remain unmounted.
1405 Otherwise, they are automatically remounted in the new location if the property
1410 or if they were mounted before the property was changed.
1411 In addition, any shared file systems are unshared and shared in the new
1413 .It Sy nbmand Ns = Ns Sy on Ns | Ns Sy off
1414 Controls whether the file system should be mounted with
1416 .Pq Non Blocking mandatory locks .
1417 This is used for SMB clients.
1418 Changes to this property only take effect when the file system is umounted and
1422 for more information on
1424 mounts. This property is not used on Linux.
1425 .It Sy overlay Ns = Ns Sy off Ns | Ns Sy on
1426 Allow mounting on a busy directory or a directory which already contains
1427 files or directories. This is the default mount behavior for Linux file systems.
1428 For consistency with OpenZFS on other platforms overlay mounts are
1432 to enable overlay mounts.
1433 .It Sy primarycache Ns = Ns Sy all Ns | Ns Sy none Ns | Ns Sy metadata
1434 Controls what is cached in the primary cache
1436 If this property is set to
1438 then both user data and metadata is cached.
1439 If this property is set to
1441 then neither user data nor metadata is cached.
1442 If this property is set to
1444 then only metadata is cached.
1445 The default value is
1447 .It Sy quota Ns = Ns Em size Ns | Ns Sy none
1448 Limits the amount of space a dataset and its descendents can consume.
1449 This property enforces a hard limit on the amount of space used.
1450 This includes all space consumed by descendents, including file systems and
1452 Setting a quota on a descendent of a dataset that already has a quota does not
1453 override the ancestor's quota, but rather imposes an additional limit.
1455 Quotas cannot be set on volumes, as the
1457 property acts as an implicit quota.
1458 .It Sy snapshot_limit Ns = Ns Em count Ns | Ns Sy none
1459 Limits the number of snapshots that can be created on a dataset and its
1463 on a descendent of a dataset that already has a
1465 does not override the ancestor's
1466 .Sy snapshot_limit ,
1467 but rather imposes an additional limit.
1468 The limit is not enforced if the user is allowed to change the limit.
1469 For example, this means that recursive snapshots taken from the global zone are
1470 counted against each delegated dataset within a zone.
1471 This feature must be enabled to be used
1473 .Xr zpool-features 5
1475 .It Sy userquota@ Ns Em user Ns = Ns Em size Ns | Ns Sy none
1476 Limits the amount of space consumed by the specified user.
1477 User space consumption is identified by the
1478 .Sy userspace@ Ns Em user
1481 Enforcement of user quotas may be delayed by several seconds.
1482 This delay means that a user might exceed their quota before the system notices
1483 that they are over quota and begins to refuse additional writes with the
1487 .Nm zfs Cm userspace
1488 subcommand for more information.
1490 Unprivileged users can only access their own groups' space usage.
1491 The root user, or a user who has been granted the
1495 can get and set everyone's quota.
1497 This property is not available on volumes, on file systems before version 4, or
1498 on pools before version 15.
1500 .Sy userquota@ Ns Em ...
1501 properties are not displayed by
1502 .Nm zfs Cm get Sy all .
1503 The user's name must be appended after the
1505 symbol, using one of the following forms:
1513 .Em POSIX numeric ID
1520 .Sy joe.smith@mydomain
1529 Files created on Linux always have POSIX owners.
1530 .It Sy userobjquota@ Ns Em user Ns = Ns Em size Ns | Ns Sy none
1535 but it limits the number of objects a user can create. Please refer to
1537 for more information about how objects are counted.
1538 .It Sy groupquota@ Ns Em group Ns = Ns Em size Ns | Ns Sy none
1539 Limits the amount of space consumed by the specified group.
1540 Group space consumption is identified by the
1541 .Sy groupused@ Ns Em group
1544 Unprivileged users can access only their own groups' space usage.
1545 The root user, or a user who has been granted the
1549 can get and set all groups' quotas.
1550 .It Sy groupobjquota@ Ns Em group Ns = Ns Em size Ns | Ns Sy none
1555 but it limits number of objects a group can consume. Please refer to
1557 for more information about how objects are counted.
1558 .It Sy readonly Ns = Ns Sy on Ns | Ns Sy off
1559 Controls whether this dataset can be modified.
1560 The default value is
1566 are equivalent to the
1572 This property can also be referred to by its shortened column name,
1574 .It Sy recordsize Ns = Ns Em size
1575 Specifies a suggested block size for files in the file system.
1576 This property is designed solely for use with database workloads that access
1577 files in fixed-size records.
1578 ZFS automatically tunes block sizes according to internal algorithms optimized
1579 for typical access patterns.
1581 For databases that create very large files but access them in small random
1582 chunks, these algorithms may be suboptimal.
1585 greater than or equal to the record size of the database can result in
1586 significant performance gains.
1587 Use of this property for general purpose file systems is strongly discouraged,
1588 and may adversely affect performance.
1590 The size specified must be a power of two greater than or equal to 512 and less
1591 than or equal to 128 Kbytes.
1594 feature is enabled on the pool, the size may be up to 1 Mbyte.
1596 .Xr zpool-features 5
1597 for details on ZFS feature flags.
1599 Changing the file system's
1601 affects only files created afterward; existing files are unaffected.
1603 This property can also be referred to by its shortened column name,
1605 .It Sy redundant_metadata Ns = Ns Sy all Ns | Ns Sy most
1606 Controls what types of metadata are stored redundantly.
1607 ZFS stores an extra copy of metadata, so that if a single block is corrupted,
1608 the amount of user data lost is limited.
1609 This extra copy is in addition to any redundancy provided at the pool level
1610 .Pq e.g. by mirroring or RAID-Z ,
1611 and is in addition to an extra copy specified by the
1614 .Pq up to a total of 3 copies .
1615 For example if the pool is mirrored,
1616 .Sy copies Ns = Ns 2 ,
1618 .Sy redundant_metadata Ns = Ns Sy most ,
1619 then ZFS stores 6 copies of most metadata, and 4 copies of data and some
1624 ZFS stores an extra copy of all metadata.
1625 If a single on-disk block is corrupt, at worst a single block of user data
1634 ZFS stores an extra copy of most types of metadata.
1635 This can improve performance of random writes, because less metadata must be
1637 In practice, at worst about 100 blocks
1642 of user data can be lost if a single on-disk block is corrupt.
1643 The exact behavior of which metadata blocks are stored redundantly may change in
1646 The default value is
1648 .It Sy refquota Ns = Ns Em size Ns | Ns Sy none
1649 Limits the amount of space a dataset can consume.
1650 This property enforces a hard limit on the amount of space used.
1651 This hard limit does not include space used by descendents, including file
1652 systems and snapshots.
1653 .It Sy refreservation Ns = Ns Em size Ns | Ns Sy none
1654 The minimum amount of space guaranteed to a dataset, not including its
1656 When the amount of space used is below this value, the dataset is treated as if
1657 it were taking up the amount of space specified by
1658 .Sy refreservation .
1661 reservation is accounted for in the parent datasets' space used, and counts
1662 against the parent datasets' quotas and reservations.
1666 is set, a snapshot is only allowed if there is enough free pool space outside of
1667 this reservation to accommodate the current number of
1669 bytes in the dataset.
1671 This property can also be referred to by its shortened column name,
1673 .It Sy relatime Ns = Ns Sy on Ns | Ns Sy off
1674 Controls the manner in which the access time is updated when
1676 is set. Turning this property on causes the access time to be updated relative
1677 to the modify or change time. Access time is only updated if the previous
1678 access time was earlier than the current modify or change time or if the
1679 existing access time hasn't been updated within the past 24 hours. The default
1686 are equivalent to the
1691 .It Sy reservation Ns = Ns Em size Ns | Ns Sy none
1692 The minimum amount of space guaranteed to a dataset and its descendants.
1693 When the amount of space used is below this value, the dataset is treated as if
1694 it were taking up the amount of space specified by its reservation.
1695 Reservations are accounted for in the parent datasets' space used, and count
1696 against the parent datasets' quotas and reservations.
1698 This property can also be referred to by its shortened column name,
1700 .It Sy secondarycache Ns = Ns Sy all Ns | Ns Sy none Ns | Ns Sy metadata
1701 Controls what is cached in the secondary cache
1703 If this property is set to
1705 then both user data and metadata is cached.
1706 If this property is set to
1708 then neither user data nor metadata is cached.
1709 If this property is set to
1711 then only metadata is cached.
1712 The default value is
1714 .It Sy setuid Ns = Ns Sy on Ns | Ns Sy off
1715 Controls whether the setuid bit is respected for the file system.
1716 The default value is
1722 are equivalent to the
1727 .It Sy sharesmb Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Em opts
1728 Controls whether the file system is shared by using
1729 .Sy Samba USERSHARES
1730 and what options are to be used. Otherwise, the file system is automatically
1731 shared and unshared with the
1735 commands. If the property is set to on, the
1737 command is invoked to create a
1740 Because SMB shares requires a resource name, a unique resource name is
1741 constructed from the dataset name. The constructed name is a copy of the
1742 dataset name except that the characters in the dataset name, which would be
1743 invalid in the resource name, are replaced with underscore (_) characters.
1744 Linux does not currently support additional options which might be available
1751 the file systems are unshared.
1753 The share is created with the ACL (Access Control List) "Everyone:F" ("F"
1754 stands for "full permissions", ie. read and write permissions) and no guest
1755 access (which means Samba must be able to authenticate a real user, system
1756 passwd/shadow, LDAP or smbpasswd based) by default. This means that any
1757 additional access control (disallow specific user specific access etc) must
1758 be done on the underlying file system.
1759 .It Sy sharenfs Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Em opts
1760 Controls whether the file system is shared via NFS, and what options are to be
1762 A file system with a
1768 command and entries in the
1771 Otherwise, the file system is automatically shared and unshared with the
1776 If the property is set to
1778 the dataset is shared using the default options:
1780 .Em sec=sys,rw,crossmnt,no_subtree_check,no_root_squash
1784 for the meaning of the default options. Otherwise, the
1786 command is invoked with options equivalent to the contents of this property.
1790 property is changed for a dataset, the dataset and any children inheriting the
1791 property are re-shared with the new options, only if the property was previously
1793 or if they were shared before the property was changed.
1794 If the new property is
1796 the file systems are unshared.
1797 .It Sy logbias Ns = Ns Sy latency Ns | Ns Sy throughput
1798 Provide a hint to ZFS about handling of synchronous requests in this dataset.
1804 ZFS will use pool log devices
1806 to handle the requests at low latency.
1811 ZFS will not use configured pool log devices.
1812 ZFS will instead optimize synchronous operations for global pool throughput and
1813 efficient use of resources.
1814 .It Sy snapdev Ns = Ns Sy hidden Ns | Ns Sy visible
1815 Controls whether the volume snapshot devices under
1816 .Em /dev/zvol/<pool>
1817 are hidden or visible. The default value is
1819 .It Sy snapdir Ns = Ns Sy hidden Ns | Ns Sy visible
1820 Controls whether the
1822 directory is hidden or visible in the root of the file system as discussed in
1826 The default value is
1828 .It Sy sync Ns = Ns Sy standard Ns | Ns Sy always Ns | Ns Sy disabled
1829 Controls the behavior of synchronous requests
1830 .Pq e.g. fsync, O_DSYNC .
1834 specified behavior of ensuring all synchronous requests are written to stable
1835 storage and all devices are flushed to ensure data is not cached by device
1837 .Pq this is the default .
1839 causes every file system transaction to be written and flushed before its
1840 system call returns.
1841 This has a large performance penalty.
1843 disables synchronous requests.
1844 File system transactions are only committed to stable storage periodically.
1845 This option will give the highest performance.
1846 However, it is very dangerous as ZFS would be ignoring the synchronous
1847 transaction demands of applications such as databases or NFS.
1848 Administrators should only use this option when the risks are understood.
1849 .It Sy version Ns = Ns Em N Ns | Ns Sy current
1850 The on-disk version of this file system, which is independent of the pool
1852 This property can only be set to later supported versions.
1856 .It Sy volsize Ns = Ns Em size
1857 For volumes, specifies the logical size of the volume.
1858 By default, creating a volume establishes a reservation of equal size.
1859 For storage pools with a version number of 9 or higher, a
1864 are reflected in an equivalent change to the reservation
1870 can only be set to a multiple of
1874 The reservation is kept equal to the volume's logical size to prevent unexpected
1875 behavior for consumers.
1876 Without the reservation, the volume could run out of space, resulting in
1877 undefined behavior or data corruption, depending on how the volume is used.
1878 These effects can also occur when the volume size is changed while it is in use
1879 .Pq particularly when shrinking the size .
1880 Extreme care should be used when adjusting the volume size.
1882 Though not recommended, a
1885 .Qq thin provisioning
1887 can be created by specifying the
1890 .Nm zfs Cm create Fl V
1891 command, or by changing the reservation after the volume has been created.
1894 is a volume where the reservation is less then the volume size.
1895 Consequently, writes to a sparse volume can fail with
1897 when the pool is low on space.
1898 For a sparse volume, changes to
1900 are not reflected in the reservation.
1901 .It Sy volmode Ns = Ns Cm default | full | geom | dev | none
1902 This property specifies how volumes should be exposed to the OS.
1905 exposes volumes as fully fledged block devices, providing maximal
1906 functionality. The value
1908 is just an alias for
1910 and is kept for compatibility.
1913 hides its partitions.
1914 Volumes with property set to
1916 are not exposed outside ZFS, but can be snapshoted, cloned, replicated, etc,
1917 that can be suitable for backup purposes.
1920 means that volumes exposition is controlled by system-wide tunable
1927 are encoded as 1, 2 and 3 respectively.
1928 The default values is
1930 .It Sy vscan Ns = Ns Sy on Ns | Ns Sy off
1931 Controls whether regular files should be scanned for viruses when a file is
1933 In addition to enabling this property, the virus scan service must also be
1934 enabled for virus scanning to occur.
1935 The default value is
1937 This property is not used on Linux.
1938 .It Sy xattr Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy sa
1939 Controls whether extended attributes are enabled for this file system. Two
1940 styles of extended attributes are supported either directory based or system
1943 The default value of
1945 enables directory based extended attributes. This style of extended attribute
1946 imposes no practical limit on either the size or number of attributes which
1947 can be set on a file. Although under Linux the
1951 system calls limit the maximum size to 64K. This is the most compatible
1952 style of extended attribute and is supported by all OpenZFS implementations.
1954 System attribute based xattrs can be enabled by setting the value to
1956 The key advantage of this type of xattr is improved performance. Storing
1957 extended attributes as system attributes significantly decreases the amount of
1958 disk IO required. Up to 64K of data may be stored per-file in the space
1959 reserved for system attributes. If there is not enough space available for
1960 an extended attribute then it will be automatically written as a directory
1961 based xattr. System attribute based extended attributes are not accessible
1962 on platforms which do not support the
1966 The use of system attribute based xattrs is strongly encouraged for users of
1967 SELinux or posix ACLs. Both of these features heavily rely of extended
1968 attributes and benefit significantly from the reduced access time.
1974 are equivalent to the
1979 .It Sy zoned Ns = Ns Sy on Ns | Ns Sy off
1980 Controls whether the dataset is managed from a non-global zone. Zones are a
1981 Solaris feature and are not relevant on Linux. The default value is
1985 The following three properties cannot be changed after the file system is
1986 created, and therefore, should be set when the file system is created.
1987 If the properties are not set with the
1991 commands, these properties are inherited from the parent dataset.
1992 If the parent dataset lacks these properties due to having been created prior to
1993 these features being supported, the new file system will have the default values
1994 for these properties.
1997 .Sy casesensitivity Ns = Ns Sy sensitive Ns | Ns
1998 .Sy insensitive Ns | Ns Sy mixed
2000 Indicates whether the file name matching algorithm used by the file system
2001 should be case-sensitive, case-insensitive, or allow a combination of both
2003 The default value for the
2011 file systems have case-sensitive file names.
2017 property indicates that the file system can support requests for both
2018 case-sensitive and case-insensitive matching behavior.
2019 Currently, case-insensitive matching behavior on a file system that supports
2020 mixed behavior is limited to the SMB server product.
2021 For more information about the
2023 value behavior, see the "ZFS Administration Guide".
2025 .Sy normalization Ns = Ns Sy none Ns | Ns Sy formC Ns | Ns
2026 .Sy formD Ns | Ns Sy formKC Ns | Ns Sy formKD
2028 Indicates whether the file system should perform a
2030 normalization of file names whenever two file names are compared, and which
2031 normalization algorithm should be used.
2032 File names are always stored unmodified, names are normalized as part of any
2034 If this property is set to a legal value other than
2038 property was left unspecified, the
2040 property is automatically set to
2042 The default value of the
2046 This property cannot be changed after the file system is created.
2047 .It Sy utf8only Ns = Ns Sy on Ns | Ns Sy off
2048 Indicates whether the file system should reject file names that include
2049 characters that are not present in the
2052 If this property is explicitly set to
2054 the normalization property must either not be explicitly set or be set to
2056 The default value for the
2060 This property cannot be changed after the file system is created.
2064 .Sy casesensitivity ,
2068 properties are also new permissions that can be assigned to non-privileged users
2069 by using the ZFS delegated administration feature.
2070 .Ss "Temporary Mount Point Properties"
2071 When a file system is mounted, either through
2073 for legacy mounts or the
2075 command for normal file systems, its mount options are set according to its
2077 The correlation between properties and mount options is as follows:
2079 PROPERTY MOUNT OPTION
2081 canmount auto/noauto
2085 relatime relatime/norelatime
2090 In addition, these options can be set on a per-mount basis using the
2092 option, without affecting the property that is stored on disk.
2093 The values specified on the command line override the values stored in the
2097 option is an alias for
2098 .Sy nodevices Ns \&, Ns Sy nosetuid .
2099 These properties are reported as
2104 If the properties are changed while the dataset is mounted, the new setting
2105 overrides any temporary settings.
2106 .Ss "User Properties"
2107 In addition to the standard native properties, ZFS supports arbitrary user
2109 User properties have no effect on ZFS behavior, but applications or
2110 administrators can use them to annotate datasets
2111 .Pq file systems, volumes, and snapshots .
2113 User property names must contain a colon
2115 character to distinguish them from native properties.
2116 They may contain lowercase letters, numbers, and the following punctuation
2125 The expected convention is that the property name is divided into two portions
2127 .Em module Ns \&: Ns Em property ,
2128 but this namespace is not enforced by ZFS.
2129 User property names can be at most 256 characters, and cannot begin with a dash
2132 When making programmatic use of user properties, it is strongly suggested to use
2137 component of property names to reduce the chance that two
2138 independently-developed packages use the same property name for different
2141 The values of user properties are arbitrary strings, are always inherited, and
2142 are never validated.
2143 All of the commands that operate on properties
2144 .Po Nm zfs Cm list ,
2149 can be used to manipulate both native properties and user properties.
2152 command to clear a user property.
2153 If the property is not defined in any parent dataset, it is removed entirely.
2154 Property values are limited to 8192 bytes.
2155 .Ss ZFS Volumes as Swap
2156 ZFS volumes may be used as swap devices. After creating the volume with the
2157 .Nm zfs Cm create Fl V
2158 command set up and enable the swap area using the
2162 commands. Do not swap to a file on a ZFS file system. A ZFS swap file
2163 configuration is not supported.
2167 feature allows for the creation of encrypted filesystems and volumes.
2169 will encrypt all user data including file and zvol data, file attributes,
2170 ACLs, permission bits, directory listings, FUID mappings, and userused /
2173 will not encrypt metadata related to the pool structure, including dataset
2174 names, dataset hierarchy, file size, file holes, and dedup tables. Key rotation
2175 is managed internally by the kernel module and changing the user's key does not
2176 require re-encrypting the entire dataset. Datasets can be scrubbed, resilvered,
2177 renamed, and deleted without the encryption keys being loaded (see the
2179 subcommand for more info on key loading).
2181 Creating an encrypted dataset requires specifying the
2185 properties at creation time, along with an optional
2189 After entering an encryption key, the
2190 created dataset will become an encryption root. Any descendant datasets will
2191 inherit their encryption key from the encryption root by default, meaning that
2192 loading, unloading, or changing the key for the encryption root will implicitly
2193 do the same for all inheriting datasets. If this inheritance is not desired,
2196 when creating the child dataset or use
2197 .Nm zfs Cm change-key
2198 to break an existing relationship, creating a new encryption root on the child.
2199 Note that the child's
2201 may match that of the parent while still creating a new encryption root, and
2204 property alone does not create a new encryption root; this would simply use a
2205 different cipher suite with the same key as its encryption root. The one
2206 exception is that clones will always use their origin's encryption key.
2207 As a result of this exception, some encryption-related properties (namely
2213 do not inherit like other ZFS properties and instead use the value determined
2214 by their encryption root. Encryption root inheritance can be tracked via the
2219 Encryption changes the behavior of a few
2221 operations. Encryption is applied after compression so compression ratios are
2222 preserved. Normally checksums in ZFS are 256 bits long, but for encrypted data
2223 the checksum is 128 bits of the user-chosen checksum and 128 bits of MAC from
2224 the encryption suite, which provides additional protection against maliciously
2225 altered data. Deduplication is still possible with encryption enabled but for
2226 security, datasets will only dedup against themselves, their snapshots, and
2229 There are a few limitations on encrypted datasets. Encrypted data cannot be
2232 feature. Encrypted datasets may not have
2233 .Sy copies Ns = Ns Em 3
2234 since the implementation stores some encryption metadata where the third copy
2235 would normally be. Since compression is applied before encryption datasets may
2236 be vulnerable to a CRIME-like attack if applications accessing the data allow
2237 for it. Deduplication with encryption will leak information about which blocks
2238 are equivalent in a dataset and will incur an extra CPU cost per block written.
2240 All subcommands that modify state are logged persistently to the pool in their
2244 Displays a help message.
2249 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
2252 Creates a new ZFS file system.
2253 The file system is automatically mounted according to the
2255 property inherited from the parent.
2256 .Bl -tag -width "-o"
2257 .It Fl o Ar property Ns = Ns Ar value
2258 Sets the specified property as if the command
2259 .Nm zfs Cm set Ar property Ns = Ns Ar value
2260 was invoked at the same time the dataset was created.
2261 Any editable ZFS property can also be set at creation time.
2264 options can be specified.
2265 An error results if the same property is specified in multiple
2269 Creates all the non-existing parent datasets.
2270 Datasets created in this manner are automatically mounted according to the
2272 property inherited from their parent.
2273 Any property specified on the command line using the
2276 If the target filesystem already exists, the operation completes successfully.
2282 .Op Fl b Ar blocksize
2283 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
2284 .Fl V Ar size Ar volume
2286 Creates a volume of the given size.
2287 The volume is exported as a block device in
2288 .Pa /dev/zvol/path ,
2291 is the name of the volume in the ZFS namespace.
2292 The size represents the logical size as exported by the device.
2293 By default, a reservation of equal size is created.
2296 is automatically rounded up to the nearest 128 Kbytes to ensure that the volume
2297 has an integral number of blocks regardless of
2299 .Bl -tag -width "-b"
2300 .It Fl b Ar blocksize
2302 .Fl o Sy volblocksize Ns = Ns Ar blocksize .
2303 If this option is specified in conjunction with
2304 .Fl o Sy volblocksize ,
2305 the resulting behavior is undefined.
2306 .It Fl o Ar property Ns = Ns Ar value
2307 Sets the specified property as if the
2308 .Nm zfs Cm set Ar property Ns = Ns Ar value
2309 command was invoked at the same time the dataset was created.
2310 Any editable ZFS property can also be set at creation time.
2313 options can be specified.
2314 An error results if the same property is specified in multiple
2318 Creates all the non-existing parent datasets.
2319 Datasets created in this manner are automatically mounted according to the
2321 property inherited from their parent.
2322 Any property specified on the command line using the
2325 If the target filesystem already exists, the operation completes successfully.
2327 Creates a sparse volume with no reservation.
2331 .Sx Native Properties
2332 section for more information about sparse volumes.
2338 .Ar filesystem Ns | Ns Ar volume
2340 Destroys the given dataset.
2341 By default, the command unshares any file systems that are currently shared,
2342 unmounts any file systems that are currently mounted, and refuses to destroy a
2343 dataset that has active dependents
2344 .Pq children or clones .
2345 .Bl -tag -width "-R"
2347 Recursively destroy all dependents, including cloned file systems outside the
2350 Force an unmount of any file systems using the
2353 This option has no effect on non-file systems or unmounted file systems.
2358 No data will be deleted.
2359 This is useful in conjunction with the
2363 flags to determine what data would be deleted.
2365 Print machine-parsable verbose information about the deleted data.
2367 Recursively destroy all children.
2369 Print verbose information about the deleted data.
2372 Extreme care should be taken when applying either the
2376 options, as they can destroy large portions of a pool and cause unexpected
2377 behavior for mounted file systems in use.
2382 .Ar filesystem Ns | Ns Ar volume Ns @ Ns Ar snap Ns
2383 .Oo % Ns Ar snap Ns Oo , Ns Ar snap Ns Oo % Ns Ar snap Oc Oc Oc Ns ...
2385 The given snapshots are destroyed immediately if and only if the
2389 option would have destroyed it.
2390 Such immediate destruction would occur, for example, if the snapshot had no
2391 clones and the user-initiated reference count were zero.
2393 If a snapshot does not qualify for immediate destruction, it is marked for
2395 In this state, it exists as a usable, visible snapshot until both of the
2396 preconditions listed above are met, at which point it is destroyed.
2398 An inclusive range of snapshots may be specified by separating the first and
2399 last snapshots with a percent sign.
2400 The first and/or last snapshots may be left blank, in which case the
2401 filesystem's oldest or newest snapshot will be implied.
2404 .Pq or ranges of snapshots
2405 of the same filesystem or volume may be specified in a comma-separated list of
2407 Only the snapshot's short name
2408 .Po the part after the
2411 should be specified when using a range or comma-separated list to identify
2413 .Bl -tag -width "-R"
2415 Recursively destroy all clones of these snapshots, including the clones,
2416 snapshots, and children.
2417 If this flag is specified, the
2419 flag will have no effect.
2421 Defer snapshot deletion.
2426 No data will be deleted.
2427 This is useful in conjunction with the
2431 flags to determine what data would be deleted.
2433 Print machine-parsable verbose information about the deleted data.
2436 .Pq or mark for deferred deletion
2437 all snapshots with this name in descendent file systems.
2439 Print verbose information about the deleted data.
2441 Extreme care should be taken when applying either the
2445 options, as they can destroy large portions of a pool and cause unexpected
2446 behavior for mounted file systems in use.
2451 .Ar filesystem Ns | Ns Ar volume Ns # Ns Ar bookmark
2453 The given bookmark is destroyed.
2458 .Oo Fl o Ar property Ns = Ns value Oc Ns ...
2459 .Ar filesystem Ns @ Ns Ar snapname Ns | Ns Ar volume Ns @ Ns Ar snapname Ns ...
2461 Creates snapshots with the given names.
2462 All previous modifications by successful system calls to the file system are
2463 part of the snapshots.
2464 Snapshots are taken atomically, so that all snapshots correspond to the same
2468 section for details.
2469 .Bl -tag -width "-o"
2470 .It Fl o Ar property Ns = Ns Ar value
2471 Sets the specified property; see
2475 Recursively create snapshots of all descendent datasets
2483 Roll back the given dataset to a previous snapshot.
2484 When a dataset is rolled back, all data that has changed since the snapshot is
2485 discarded, and the dataset reverts to the state at the time of the snapshot.
2486 By default, the command refuses to roll back to a snapshot other than the most
2488 In order to do so, all intermediate snapshots and bookmarks must be destroyed by
2495 options do not recursively destroy the child snapshots of a recursive snapshot.
2496 Only direct snapshots of the specified filesystem are destroyed by either of
2498 To completely roll back a recursive snapshot, you must rollback the individual
2500 .Bl -tag -width "-R"
2502 Destroy any more recent snapshots and bookmarks, as well as any clones of those
2507 option to force an unmount of any clone file systems that are to be destroyed.
2509 Destroy any snapshots and bookmarks more recent than the one specified.
2515 .Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
2516 .Ar snapshot Ar filesystem Ns | Ns Ar volume
2518 Creates a clone of the given snapshot.
2521 section for details.
2522 The target dataset can be located anywhere in the ZFS hierarchy, and is created
2523 as the same type as the original.
2524 .Bl -tag -width "-o"
2525 .It Fl o Ar property Ns = Ns Ar value
2526 Sets the specified property; see
2530 Creates all the non-existing parent datasets.
2531 Datasets created in this manner are automatically mounted according to the
2533 property inherited from their parent.
2534 If the target filesystem or volume already exists, the operation completes
2540 .Ar clone-filesystem
2542 Promotes a clone file system to no longer be dependent on its
2545 This makes it possible to destroy the file system that the clone was created
2547 The clone parent-child dependency relationship is reversed, so that the origin
2548 file system becomes a clone of the specified file system.
2550 The snapshot that was cloned, and any snapshots previous to this snapshot, are
2551 now owned by the promoted clone.
2552 The space they use moves from the origin file system to the promoted clone, so
2553 enough space must be available to accommodate these snapshots.
2554 No new space is consumed by this operation, but the space accounting is
2556 The promoted clone must not have any conflicting snapshot names of its own.
2559 subcommand can be used to rename any conflicting snapshots.
2564 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2565 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2571 .Ar filesystem Ns | Ns Ar volume
2572 .Ar filesystem Ns | Ns Ar volume
2574 Renames the given dataset.
2575 The new target can be located anywhere in the ZFS hierarchy, with the exception
2577 Snapshots can only be renamed within the parent file system or volume.
2578 When renaming a snapshot, the parent file system of the snapshot does not need
2579 to be specified as part of the second argument.
2580 Renamed file systems can inherit new mount points, in which case they are
2581 unmounted and remounted at the new mount point.
2582 .Bl -tag -width "-a"
2584 Force unmount any filesystems that need to be unmounted in the process.
2586 Creates all the nonexistent parent datasets.
2587 Datasets created in this manner are automatically mounted according to the
2589 property inherited from their parent.
2595 .Ar snapshot Ar snapshot
2597 Recursively rename the snapshots of all descendent datasets.
2598 Snapshots are the only dataset that can be renamed recursively.
2602 .Op Fl r Ns | Ns Fl d Ar depth
2604 .Oo Fl o Ar property Ns Oo , Ns Ar property Oc Ns ... Oc
2605 .Oo Fl s Ar property Oc Ns ...
2606 .Oo Fl S Ar property Oc Ns ...
2607 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2608 .Oo Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Oc Ns ...
2610 Lists the property information for the given datasets in tabular form.
2611 If specified, you can list property information by the absolute pathname or the
2613 By default, all file systems and volumes are displayed.
2614 Snapshots are displayed if the
2621 The following fields are displayed,
2622 .Sy name Ns \&, Ns Sy used Ns \&, Ns Sy available Ns \&, Ns Sy referenced Ns \&, Ns
2624 .Bl -tag -width "-H"
2626 Used for scripting mode.
2627 Do not print headers and separate fields by a single tab instead of arbitrary
2629 .It Fl S Ar property
2632 option, but sorts by property in descending order.
2634 Recursively display any children of the dataset, limiting the recursion to
2640 will display only the dataset and its direct children.
2641 .It Fl o Ar property
2642 A comma-separated list of properties to display.
2643 The property must be:
2646 One of the properties described in the
2647 .Sx Native Properties
2654 to display the dataset name
2658 to display space usage properties on file systems and volumes.
2659 This is a shortcut for specifying
2660 .Fl o Sy name Ns \&, Ns Sy avail Ns \&, Ns Sy used Ns \&, Ns Sy usedsnap Ns \&, Ns
2661 .Sy usedds Ns \&, Ns Sy usedrefreserv Ns \&, Ns Sy usedchild Fl t
2662 .Sy filesystem Ns \&, Ns Sy volume
2666 Display numbers in parsable
2670 Recursively display any children of the dataset on the command line.
2671 .It Fl s Ar property
2672 A property for sorting the output by column in ascending order based on the
2673 value of the property.
2674 The property must be one of the properties described in the
2676 section, or the special value
2678 to sort by the dataset name.
2679 Multiple properties can be specified at one time using multiple
2684 options are evaluated from left to right in decreasing order of importance.
2685 The following is a list of sorting criteria:
2688 Numeric types sort in numeric order.
2690 String types sort in alphabetical order.
2692 Types inappropriate for a row sort that row to the literal bottom, regardless of
2693 the specified ordering.
2696 If no sorting options are specified the existing behavior of
2700 A comma-separated list of types to display, where
2709 For example, specifying
2711 displays only snapshots.
2716 .Ar property Ns = Ns Ar value Oo Ar property Ns = Ns Ar value Oc Ns ...
2717 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
2719 Sets the property or list of properties to the given value(s) for each dataset.
2720 Only some properties can be edited.
2723 section for more information on what properties can be set and acceptable
2725 Numeric values can be specified as exact values, or in a human-readable form
2727 .Sy B , K , M , G , T , P , E , Z
2728 .Po for bytes, kilobytes, megabytes, gigabytes, terabytes, petabytes, exabytes,
2729 or zettabytes, respectively
2731 User properties can be set on snapshots.
2732 For more information, see the
2738 .Op Fl r Ns | Ns Fl d Ar depth
2740 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
2741 .Oo Fl s Ar source Ns Oo , Ns Ar source Oc Ns ... Oc
2742 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2743 .Cm all | Ar property Ns Oo , Ns Ar property Oc Ns ...
2744 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns | Ns Ar bookmark Ns ...
2746 Displays properties for the given datasets.
2747 If no datasets are specified, then the command displays properties for all
2748 datasets on the system.
2749 For each property, the following columns are displayed:
2752 property Property name
2753 value Property value
2754 source Property source. Can either be local, default,
2755 temporary, inherited, or none (-).
2758 All columns are displayed by default, though this can be controlled by using the
2761 This command takes a comma-separated list of properties as described in the
2762 .Sx Native Properties
2769 can be used to display all properties that apply to the given dataset's type
2770 .Pq filesystem, volume, snapshot, or bookmark .
2771 .Bl -tag -width "-H"
2773 Display output in a form more easily parsed by scripts.
2774 Any headers are omitted, and fields are explicitly separated by a single tab
2775 instead of an arbitrary amount of space.
2777 Recursively display any children of the dataset, limiting the recursion to
2781 will display only the dataset and its direct children.
2783 A comma-separated list of columns to display.
2784 .Sy name Ns \&, Ns Sy property Ns \&, Ns Sy value Ns \&, Ns Sy source
2785 is the default value.
2787 Display numbers in parsable
2791 Recursively display properties for any children.
2793 A comma-separated list of sources to display.
2794 Those properties coming from a source other than those in this list are ignored.
2795 Each source must be one of the following:
2802 The default value is all sources.
2804 A comma-separated list of types to display, where
2818 .Ar property Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
2820 Clears the specified property, causing it to be inherited from an ancestor,
2821 restored to default if no ancestor has the property set, or with the
2823 option reverted to the received value if one exists.
2826 section for a listing of default values, and details on which properties can be
2828 .Bl -tag -width "-r"
2830 Recursively inherit the given property for all children.
2832 Revert the property to the received value if one exists; otherwise operate as
2835 option was not specified.
2841 Displays a list of file systems that are not the most recent version.
2847 Displays a list of currently supported file system versions.
2853 .Fl a | Ar filesystem
2855 Upgrades file systems to a new on-disk version.
2856 Once this is done, the file systems will no longer be accessible on systems
2857 running older versions of the software.
2859 streams generated from new snapshots of these file systems cannot be accessed on
2860 systems running older versions of the software.
2862 In general, the file system version is independent of the pool version.
2865 for information on the
2866 .Nm zpool Cm upgrade
2869 In some cases, the file system version and the pool version are interrelated and
2870 the pool version must be upgraded before the file system version can be
2872 .Bl -tag -width "-V"
2874 Upgrade to the specified
2878 flag is not specified, this command upgrades to the most recent version.
2880 option can only be used to increase the version number, and only up to the most
2881 recent version supported by this software.
2883 Upgrade all file systems on all imported pools.
2885 Upgrade the specified file system.
2887 Upgrade the specified file system and all descendent file systems.
2893 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
2894 .Oo Fl s Ar field Oc Ns ...
2895 .Oo Fl S Ar field Oc Ns ...
2896 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2897 .Ar filesystem Ns | Ns Ar snapshot
2899 Displays space consumed by, and quotas on, each user in the specified filesystem
2901 This corresponds to the
2902 .Sy userused@ Ns Em user ,
2903 .Sy userobjused@ Ns Em user ,
2904 .Sy userquota@ Ns Em user,
2906 .Sy userobjquota@ Ns Em user
2908 .Bl -tag -width "-H"
2910 Do not print headers, use tab-delimited output.
2912 Sort by this field in reverse order.
2916 Translate SID to POSIX ID.
2917 The POSIX ID may be ephemeral if no mapping exists.
2918 Normal POSIX interfaces
2923 perform this translation, so the
2925 option allows the output from
2926 .Nm zfs Cm userspace
2927 to be compared directly with those utilities.
2930 may lead to confusion if some files were created by an SMB user before a
2931 SMB-to-POSIX name mapping was established.
2932 In such a case, some files will be owned by the SMB entity and some by the POSIX
2936 option will report that the POSIX entity has the total usage and quota for both.
2938 Print numeric ID instead of user/group name.
2939 .It Fl o Ar field Ns Oo , Ns Ar field Oc Ns ...
2940 Display only the specified fields from the following set:
2945 The default is to display all fields.
2951 Sort output by this field.
2956 flags may be specified multiple times to sort first by one field, then by
2959 .Fl s Sy type Fl s Sy name .
2960 .It Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
2961 Print only the specified types from the following set:
2968 .Fl t Sy posixuser Ns \&, Ns Sy smbuser .
2969 The default can be changed to include group types.
2975 .Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
2976 .Oo Fl s Ar field Oc Ns ...
2977 .Oo Fl S Ar field Oc Ns ...
2978 .Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2979 .Ar filesystem Ns | Ns Ar snapshot
2981 Displays space consumed by, and quotas on, each group in the specified
2982 filesystem or snapshot.
2983 This subcommand is identical to
2984 .Nm zfs Cm userspace ,
2985 except that the default types to display are
2986 .Fl t Sy posixgroup Ns \&, Ns Sy smbgroup .
2991 Displays all ZFS file systems currently mounted.
2997 .Fl a | Ar filesystem
2999 Mounts ZFS file systems.
3000 .Bl -tag -width "-O"
3002 Perform an overlay mount.
3005 for more information.
3007 Mount all available ZFS file systems.
3008 Invoked automatically as part of the boot process.
3010 Mount the specified filesystem.
3012 An optional, comma-separated list of mount options to use temporarily for the
3013 duration of the mount.
3015 .Sx Temporary Mount Point Properties
3016 section for details.
3018 Load keys for encrypted filesystems as they are being mounted. This is
3019 equivalent to executing
3021 on each encryption root before mounting it. Note that if a filesystem has a
3025 this will cause the terminal to interactively block after asking for the key.
3027 Report mount progress.
3033 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
3035 Unmounts currently mounted ZFS file systems.
3036 .Bl -tag -width "-a"
3038 Unmount all available ZFS file systems.
3039 Invoked automatically as part of the shutdown process.
3040 .It Ar filesystem Ns | Ns Ar mountpoint
3041 Unmount the specified filesystem.
3042 The command can also be given a path to a ZFS file system mount point on the
3045 Forcefully unmount the file system, even if it is currently in use.
3050 .Fl a | Ar filesystem
3052 Shares available ZFS file systems.
3053 .Bl -tag -width "-a"
3055 Share all available ZFS file systems.
3056 Invoked automatically as part of the boot process.
3058 Share the specified filesystem according to the
3063 File systems are shared when the
3072 .Fl a | Ar filesystem Ns | Ns Ar mountpoint
3074 Unshares currently shared ZFS file systems.
3075 .Bl -tag -width "-a"
3077 Unshare all available ZFS file systems.
3078 Invoked automatically as part of the shutdown process.
3079 .It Ar filesystem Ns | Ns Ar mountpoint
3080 Unshare the specified filesystem.
3081 The command can also be given a path to a ZFS file system shared on the system.
3086 .Ar snapshot bookmark
3088 Creates a bookmark of the given snapshot.
3089 Bookmarks mark the point in time when the snapshot was created, and can be used
3090 as the incremental source for a
3094 This feature must be enabled to be used.
3096 .Xr zpool-features 5
3097 for details on ZFS feature flags and the
3104 .Op Oo Fl I Ns | Ns Fl i Oc Ar snapshot
3107 Creates a stream representation of the second
3109 which is written to standard output.
3110 The output can be redirected to a file or to a different system
3111 .Po for example, using
3114 By default, a full stream is generated.
3115 .Bl -tag -width "-D"
3117 Generate a deduplicated stream.
3118 Blocks which would have been sent multiple times in the send stream will only be
3120 The receiving system must also support this feature to receive a deduplicated
3122 This flag can be used regardless of the dataset's
3124 property, but performance will be much better if the filesystem uses a
3125 dedup-capable checksum
3129 .It Fl I Ar snapshot
3130 Generate a stream package that sends all intermediary snapshots from the first
3131 snapshot to the second snapshot.
3135 .Fl i Em @a Em fs@b Ns \&; Fl i Em @b Em fs@c Ns \&; Fl i Em @c Em fs@d .
3136 The incremental source may be specified as with the
3139 .It Fl L, -large-block
3140 Generate a stream which may contain blocks larger than 128KB.
3141 This flag has no effect if the
3143 pool feature is disabled, or if the
3145 property of this filesystem has never been set above 128KB.
3146 The receiving system must have the
3148 pool feature enabled as well.
3150 .Xr zpool-features 5
3151 for details on ZFS feature flags and the
3155 Print machine-parsable verbose information about the stream package generated.
3156 .It Fl R, -replicate
3157 Generate a replication stream package, which will replicate the specified
3158 file system, and all descendent file systems, up to the named snapshot.
3159 When received, all properties, snapshots, descendent file systems, and clones
3166 flags are used in conjunction with the
3168 flag, an incremental replication stream is generated.
3169 The current values of properties, and current snapshot and file system names are
3170 set when the stream is received.
3173 flag is specified when this stream is received, snapshots and file systems that
3174 do not exist on the sending side are destroyed.
3176 Generate a more compact stream by using
3178 records for blocks which are stored more compactly on disk by the
3181 This flag has no effect if the
3183 feature is disabled.
3184 The receiving system must have the
3189 feature is active on the sending system, then the receiving system must have
3190 that feature enabled as well. Datasets that are sent with this flag may not be
3191 received as an encrypted dataset, since encrypted datasets cannot use the
3195 .Xr zpool-features 5
3196 for details on ZFS feature flags and the
3199 .It Fl c, -compressed
3200 Generate a more compact stream by using compressed WRITE records for blocks
3201 which are compressed on disk and in memory
3204 property for details
3208 feature is active on the sending system, then the receiving system must have
3209 that feature enabled as well.
3212 feature is enabled on the sending system but the
3214 option is not supplied in conjunction with
3216 then the data will be decompressed before sending so it can be split into
3217 smaller block sizes.
3219 For encrypted datasets, send data exactly as it exists on disk. This allows
3220 backups to be taken even if encryption keys are not currently loaded. The
3221 backup may then be received on an untrusted machine since that machine will
3222 not have the encryption keys to read the protected data or alter it without
3223 being detected. Upon being received, the dataset will have the same encryption
3224 keys as it did on the send side, although the
3226 property will be defaulted to
3228 if not otherwise provided. For unencrypted datasets, this flag will be
3231 Note that if you do not use this flag for sending encrypted datasets, data will
3232 be sent unencrypted and may be re-encrypted with a different encryption key on
3233 the receiving system, which will disable the ability to do a raw send to that
3234 system for incrementals.
3235 .It Fl i Ar snapshot
3236 Generate an incremental stream from the first
3238 .Pq the incremental source
3241 .Pq the incremental target .
3242 The incremental source can be specified as the last component of the snapshot
3246 character and following
3248 and it is assumed to be from the same file system as the incremental target.
3250 If the destination is a clone, the source may be the origin snapshot, which must
3253 .Em pool/fs@origin ,
3261 Do not generate any actual send data.
3262 This is useful in conjunction with the
3266 flags to determine what data will be sent.
3267 In this case, the verbose output will be written to standard output
3268 .Po contrast with a non-dry-run, where the stream is written to standard output
3269 and the verbose output goes to standard error
3272 Include the dataset's properties in the stream.
3273 This flag is implicit when
3276 The receiving system must also support this feature. Sends of encrypted datasets
3279 when using this flag.
3281 Print verbose information about the stream package generated.
3282 This information includes a per-second report of how much data has been sent.
3284 The format of the stream is committed.
3285 You will be able to receive your streams on future versions of ZFS.
3291 .Op Fl i Ar snapshot Ns | Ns Ar bookmark
3292 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
3294 Generate a send stream, which may be of a filesystem, and may be incremental
3296 If the destination is a filesystem or volume, the pool must be read-only, or the
3297 filesystem must not be mounted.
3298 When the stream generated from a filesystem or volume is received, the default
3299 snapshot name will be
3301 .Bl -tag -width "-L"
3302 .It Fl L, -large-block
3303 Generate a stream which may contain blocks larger than 128KB.
3304 This flag has no effect if the
3306 pool feature is disabled, or if the
3308 property of this filesystem has never been set above 128KB.
3309 The receiving system must have the
3311 pool feature enabled as well.
3313 .Xr zpool-features 5
3314 for details on ZFS feature flags and the
3318 Print machine-parsable verbose information about the stream package generated.
3319 .It Fl c, -compressed
3320 Generate a more compact stream by using compressed WRITE records for blocks
3321 which are compressed on disk and in memory
3324 property for details
3328 feature is active on the sending system, then the receiving system must have
3329 that feature enabled as well.
3332 feature is enabled on the sending system but the
3334 option is not supplied in conjunction with
3336 then the data will be decompressed before sending so it can be split into
3337 smaller block sizes.
3339 For encrypted datasets, send data exactly as it exists on disk. This allows
3340 backups to be taken even if encryption keys are not currently loaded. The
3341 backup may then be received on an untrusted machine since that machine will
3342 not have the encryption keys to read the protected data or alter it without
3343 being detected. Upon being received, the dataset will have the same encryption
3344 keys as it did on the send side, although the
3346 property will be defaulted to
3348 if not otherwise provided. For unencrypted datasets, this flag will be
3351 Note that if you do not use this flag for sending encrypted datasets, data will
3352 be sent unencrypted and may be re-encrypted with a different encryption key on
3353 the receiving system, which will disable the ability to do a raw send to that
3354 system for incrementals.
3356 Generate a more compact stream by using
3358 records for blocks which are stored more compactly on disk by the
3361 This flag has no effect if the
3363 feature is disabled.
3364 The receiving system must have the
3369 feature is active on the sending system, then the receiving system must have
3370 that feature enabled as well. Datasets that are sent with this flag may not be
3371 received as an encrypted dataset, since encrypted datasets cannot use the
3375 .Xr zpool-features 5
3376 for details on ZFS feature flags and the
3379 .It Fl i Ar snapshot Ns | Ns Ar bookmark
3380 Generate an incremental send stream.
3381 The incremental source must be an earlier snapshot in the destination's history.
3382 It will commonly be an earlier snapshot in the destination's file system, in
3383 which case it can be specified as the last component of the name
3388 character and following
3391 If the incremental target is a clone, the incremental source can be the origin
3392 snapshot, or an earlier snapshot in the origin's filesystem, or the origin's
3398 Do not generate any actual send data.
3399 This is useful in conjunction with the
3403 flags to determine what data will be sent.
3404 In this case, the verbose output will be written to standard output
3405 .Po contrast with a non-dry-run, where the stream is written to standard output
3406 and the verbose output goes to standard error
3409 Print verbose information about the stream package generated.
3410 This information includes a per-second report of how much data has been sent.
3417 .Ar receive_resume_token
3419 Creates a send stream which resumes an interrupted receive.
3421 .Ar receive_resume_token
3422 is the value of this property on the filesystem or volume that was being
3424 See the documentation for
3431 .Op Fl o Sy origin Ns = Ns Ar snapshot
3432 .Op Fl o Ar property Ns = Ns Ar value
3433 .Op Fl x Ar property
3434 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
3440 .Op Fl d Ns | Ns Fl e
3441 .Op Fl o Sy origin Ns = Ns Ar snapshot
3442 .Op Fl o Ar property Ns = Ns Ar value
3443 .Op Fl x Ar property
3446 Creates a snapshot whose contents are as specified in the stream provided on
3448 If a full stream is received, then a new file system is created as well.
3449 Streams are created using the
3451 subcommand, which by default creates a full stream.
3453 can be used as an alias for
3456 If an incremental stream is received, then the destination file system must
3457 already exist, and its most recent snapshot must match the incremental stream's
3461 the destination device link is destroyed and recreated, which means the
3463 cannot be accessed during the
3467 When a snapshot replication package stream that is generated by using the
3468 .Nm zfs Cm send Fl R
3469 command is received, any snapshots that do not exist on the sending location are
3470 destroyed by using the
3471 .Nm zfs Cm destroy Fl d
3475 .Fl o Em property Ns = Ns Ar value
3478 is specified, it applies to the effective value of the property throughout
3479 the entire subtree of replicated datasets. Effective property values will be
3484 ) on the topmost in the replicated subtree. In descendant datasets, if the
3485 property is set by the send stream, it will be overridden by forcing the
3486 property to be inherited from the top‐most file system. Received properties
3487 are retained in spite of being overridden and may be restored with
3488 .Nm zfs Cm inherit Fl S .
3490 .Fl o Sy origin Ns = Ns Em snapshot
3491 is a special case because, even if
3493 is a read-only property and cannot be set, it's allowed to receive the send
3494 stream as a clone of the given snapshot.
3496 Raw encrypted send streams (created with
3497 .Nm zfs Cm send Fl w
3498 ) may only be received as is, and cannot be re-encrypted, decrypted, or
3499 recompressed by the receive process. Unencrypted streams can be received as
3500 encrypted datasets, either through inheritance or by specifying encryption
3505 The name of the snapshot
3506 .Pq and file system, if a full stream is received
3507 that this subcommand creates depends on the argument type and the use of the
3513 If the argument is a snapshot name, the specified
3516 If the argument is a file system or volume name, a snapshot with the same name
3517 as the sent snapshot is created within the specified
3525 options are specified, the provided target snapshot name is used exactly as
3532 options cause the file system name of the target snapshot to be determined by
3533 appending a portion of the sent snapshot's name to the specified target
3537 option is specified, all but the first element of the sent snapshot's file
3539 .Pq usually the pool name
3540 is used and any required intermediate file systems within the specified one are
3544 option is specified, then only the last element of the sent snapshot's file
3546 .Pq i.e. the name of the source file system itself
3547 is used as the target file system name.
3548 .Bl -tag -width "-F"
3550 Force a rollback of the file system to the most recent snapshot before
3551 performing the receive operation.
3552 If receiving an incremental replication stream
3553 .Po for example, one generated by
3554 .Nm zfs Cm send Fl R Op Fl i Ns | Ns Fl I
3556 destroy snapshots and file systems that do not exist on the sending side.
3558 Discard the first element of the sent snapshot's file system name, using the
3559 remaining elements to determine the name of the target file system for the new
3560 snapshot as described in the paragraph above.
3562 Discard all but the last element of the sent snapshot's file system name, using
3563 that element to determine the name of the target file system for the new
3564 snapshot as described in the paragraph above.
3566 Do not actually receive the stream.
3567 This can be useful in conjunction with the
3569 option to verify the name the receive operation would use.
3570 .It Fl o Sy origin Ns = Ns Ar snapshot
3571 Forces the stream to be received as a clone of the given snapshot.
3572 If the stream is a full send stream, this will create the filesystem
3573 described by the stream as a clone of the specified snapshot.
3574 Which snapshot was specified will not affect the success or failure of the
3575 receive, as long as the snapshot does exist.
3576 If the stream is an incremental send stream, all the normal verification will be
3578 .It Fl o Em property Ns = Ns Ar value
3579 Sets the specified property as if the command
3580 .Nm zfs Cm set Em property Ns = Ns Ar value
3581 was invoked immediately before the receive. When receiving a stream from
3582 .Nm zfs Cm send Fl R ,
3583 causes the property to be inherited by all descendant datasets, as through
3584 .Nm zfs Cm inherit Em property
3585 was run on any descendant datasets that have this property set on the
3588 Any editable property can be set at receive time. Set-once properties bound
3589 to the received data, such as
3592 .Sy casesensitivity ,
3593 cannot be set at receive time even when the datasets are newly created by
3594 .Nm zfs Cm receive .
3595 Additionally both settable properties
3599 cannot be set at receive time.
3603 option may be specified multiple times, for different properties. An error
3604 results if the same property is specified in multiple
3610 If the receive is interrupted, save the partially received state, rather
3612 Interruption may be due to premature termination of the stream
3613 .Po e.g. due to network failure or failure of the remote system
3614 if the stream is being read over a network connection
3616 a checksum error in the stream, termination of the
3618 process, or unclean shutdown of the system.
3620 The receive can be resumed with a stream generated by
3621 .Nm zfs Cm send Fl t Ar token ,
3625 .Sy receive_resume_token
3626 property of the filesystem or volume which is received into.
3628 To use this flag, the storage pool must have the
3629 .Sy extensible_dataset
3632 .Xr zpool-features 5
3633 for details on ZFS feature flags.
3635 File system that is associated with the received stream is not mounted.
3637 Print verbose information about the stream and the time required to perform the
3639 .It Fl x Em property
3640 Ensures that the effective value of the specified property after the
3641 receive is unaffected by the value of that property in the send stream (if any),
3642 as if the property had been excluded from the send stream.
3644 If the specified property is not present in the send stream, this option does
3647 If a received property needs to be overridden, the effective value will be
3648 set or inherited, depending on whether the property is inheritable or not.
3650 In the case of an incremental update,
3652 leaves any existing local setting or explicit inheritance unchanged.
3656 restrictions on set-once and special properties apply equally to
3663 .Ar filesystem Ns | Ns Ar volume
3665 Abort an interrupted
3666 .Nm zfs Cm receive Fl s ,
3667 deleting its saved partially received state.
3671 .Ar filesystem Ns | Ns Ar volume
3673 Displays permissions that have been delegated on the specified filesystem or
3675 See the other forms of
3677 for more information.
3679 Delegations are supported under Linux with the exception of
3687 These permissions cannot be delegated because the Linux
3689 command restricts modifications of the global namespace to the root user.
3694 .Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
3695 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3696 .Ar setname Oc Ns ...
3697 .Ar filesystem Ns | Ns Ar volume
3702 .Fl e Ns | Ns Sy everyone
3703 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3704 .Ar setname Oc Ns ...
3705 .Ar filesystem Ns | Ns Ar volume
3707 Delegates ZFS administration permission for the file systems to non-privileged
3709 .Bl -tag -width "-d"
3711 Allow only for the descendent file systems.
3712 .It Fl e Ns | Ns Sy everyone
3713 Specifies that the permissions be delegated to everyone.
3714 .It Fl g Ar group Ns Oo , Ns Ar group Oc Ns ...
3715 Explicitly specify that permissions are delegated to the group.
3719 only for the specified file system.
3720 .It Fl u Ar user Ns Oo , Ns Ar user Oc Ns ...
3721 Explicitly specify that permissions are delegated to the user.
3722 .It Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
3723 Specifies to whom the permissions are delegated.
3724 Multiple entities can be specified as a comma-separated list.
3727 options are specified, then the argument is interpreted preferentially as the
3730 then as a user name, and lastly as a group name.
3731 To specify a user or group named
3738 To specify a group with the same name as a user, use the
3742 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3743 .Ar setname Oc Ns ...
3745 The permissions to delegate.
3746 Multiple permissions may be specified as a comma-separated list.
3747 Permission names are the same as ZFS subcommand and property names.
3748 See the property list below.
3749 Property set names, which begin with
3754 form below for details.
3759 options are specified, or both are, then the permissions are allowed for the
3760 file system or volume, and all of its descendents.
3762 Permissions are generally the ability to use a ZFS subcommand or change a ZFS
3764 The following permissions are available:
3767 allow subcommand Must also have the permission that is
3769 clone subcommand Must also have the 'create' ability and
3770 'mount' ability in the origin file system
3771 create subcommand Must also have the 'mount' ability
3772 destroy subcommand Must also have the 'mount' ability
3773 diff subcommand Allows lookup of paths within a dataset
3774 given an object number, and the ability
3775 to create snapshots necessary to
3777 load-key subcommand Allows loading and unloading of encryption key
3778 (see 'zfs load-key' and 'zfs unload-key').
3779 change-key subcommand Allows changing an encryption key via
3781 mount subcommand Allows mount/umount of ZFS datasets
3782 promote subcommand Must also have the 'mount' and 'promote'
3783 ability in the origin file system
3784 receive subcommand Must also have the 'mount' and 'create'
3786 rename subcommand Must also have the 'mount' and 'create'
3787 ability in the new parent
3788 rollback subcommand Must also have the 'mount' ability
3790 share subcommand Allows sharing file systems over NFS
3792 snapshot subcommand Must also have the 'mount' ability
3794 groupquota other Allows accessing any groupquota@...
3796 groupused other Allows reading any groupused@... property
3797 userprop other Allows changing any user property
3798 userquota other Allows accessing any userquota@...
3800 userused other Allows reading any userused@... property
3806 casesensitivity property
3808 compression property
3812 filesystem_limit property
3815 normalization property
3816 primarycache property
3821 refreservation property
3822 reservation property
3823 secondarycache property
3828 snapshot_limit property
3831 volblocksize property
3841 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3842 .Ar setname Oc Ns ...
3843 .Ar filesystem Ns | Ns Ar volume
3848 These permissions are granted
3850 to the creator of any newly-created descendent file system.
3854 .Fl s No @ Ns Ar setname
3855 .Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3856 .Ar setname Oc Ns ...
3857 .Ar filesystem Ns | Ns Ar volume
3859 Defines or adds permissions to a permission set.
3860 The set can be used by other
3862 commands for the specified file system and its descendents.
3863 Sets are evaluated dynamically, so changes to a set are immediately reflected.
3864 Permission sets follow the same naming restrictions as ZFS file systems, but the
3865 name must begin with
3867 and can be no more than 64 characters long.
3872 .Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
3873 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3874 .Ar setname Oc Ns ... Oc
3875 .Ar filesystem Ns | Ns Ar volume
3880 .Fl e Ns | Ns Sy everyone
3881 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3882 .Ar setname Oc Ns ... Oc
3883 .Ar filesystem Ns | Ns Ar volume
3889 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3890 .Ar setname Oc Ns ... Oc
3891 .Ar filesystem Ns | Ns Ar volume
3893 Removes permissions that were granted with the
3896 No permissions are explicitly denied, so other permissions granted are still in
3898 For example, if the permission is granted by an ancestor.
3899 If no permissions are specified, then all permissions for the specified
3911 only removes the permissions that were granted to everyone, not all permissions
3912 for every user and group.
3915 command for a description of the
3918 .Bl -tag -width "-r"
3920 Recursively remove the permissions from this file system and all descendents.
3926 .Fl s No @ Ns Ar setname
3927 .Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3928 .Ar setname Oc Ns ... Oc
3929 .Ar filesystem Ns | Ns Ar volume
3931 Removes permissions from a permission set.
3932 If no permissions are specified, then all permissions are removed, thus removing
3938 .Ar tag Ar snapshot Ns ...
3940 Adds a single reference, named with the
3942 argument, to the specified snapshot or snapshots.
3943 Each snapshot has its own tag namespace, and tags must be unique within that
3946 If a hold exists on a snapshot, attempts to destroy that snapshot by using the
3950 .Bl -tag -width "-r"
3952 Specifies that a hold with the given tag is applied recursively to the snapshots
3953 of all descendent file systems.
3961 Lists all existing user references for the given snapshot or snapshots.
3962 .Bl -tag -width "-r"
3964 Lists the holds that are set on the named descendent snapshots, in addition to
3965 listing the holds on the named snapshot.
3971 .Ar tag Ar snapshot Ns ...
3973 Removes a single reference, named with the
3975 argument, from the specified snapshot or snapshots.
3976 The tag must already exist for each snapshot.
3977 If a hold exists on a snapshot, attempts to destroy that snapshot by using the
3981 .Bl -tag -width "-r"
3983 Recursively releases a hold with the given tag on the snapshots of all
3984 descendent file systems.
3990 .Ar snapshot Ar snapshot Ns | Ns Ar filesystem
3992 Display the difference between a snapshot of a given filesystem and another
3993 snapshot of that filesystem from a later time or the current contents of the
3995 The first column is a character indicating the type of change, the other columns
3996 indicate pathname, new pathname
3997 .Pq in case of rename ,
3998 change in link count, and optionally file type and/or change time.
3999 The types of change are:
4001 - The path has been removed
4002 + The path has been created
4003 M The path has been modified
4004 R The path has been renamed
4006 .Bl -tag -width "-F"
4008 Display an indication of the type of file, in a manner similar to the
4024 Give more parsable tab-separated output, without header lines and without
4027 Display the path's inode change time as the first column of output.
4033 .Op Fl L Ar keylocation
4034 .Fl a | Ar filesystem
4038 allowing it and all children that inherit the
4040 property to be accessed. The key will be expected in the format specified by the
4042 and location specified by the
4044 property. Note that if the
4048 the terminal will interactively wait for the key to be entered. Loading a key
4049 will not automatically mount the dataset. If that functionality is desired,
4050 .Nm zfs Cm mount Sy -l
4051 will ask for the key and mount the dataset. Once the key is loaded the
4053 property will become
4055 .Bl -tag -width "-r"
4057 Recursively loads the keys for the specified filesystem and all descendent
4060 Loads the keys for all encryption roots in all imported pools.
4064 load-key. This will cause zfs to simply check that the
4065 provided key is correct. This command may be run even if the key is already
4067 .It Fl L Ar keylocation
4072 property. This will not change the value of the property on the dataset. Note
4073 that if used with either
4078 may only be given as
4085 .Fl a | Ar filesystem
4087 Unloads a key from ZFS, removing the ability to access the dataset and all of
4088 its children that inherit the
4090 property. This requires that the dataset is not currently open or mounted. Once
4091 the key is unloaded the
4093 property will become
4095 .Bl -tag -width "-r"
4097 Recursively unloads the keys for the specified filesystem and all descendent
4100 Unloads the keys for all encryption roots in all imported pools.
4106 .Op Fl o Ar keylocation Ns = Ns Ar value
4107 .Op Fl o Ar keyformat Ns = Ns Ar value
4108 .Op Fl o Ar pbkdf2iters Ns = Ns Ar value
4118 Allows a user to change the encryption key used to access a dataset. This
4119 command requires that the existing key for the dataset is already loaded into
4120 ZFS. This command may also be used to change the
4125 properties as needed. If the dataset was not previously an encryption root it
4126 will become one. Alternatively, the
4128 flag may be provided to cause an encryption root to inherit the parent's key
4130 .Bl -tag -width "-r"
4132 Ensures the key is loaded before attempting to change the key. This is
4133 effectively equivalent to
4134 .Qq Nm zfs Cm load-key Ar filesystem ; Nm zfs Cm change-key Ar filesystem
4135 .It Fl o Ar property Ns = Ns Ar value
4136 Allows the user to set encryption key properties (
4141 ) while changing the key. This is the only way to alter
4145 after the dataset has been created.
4147 Indicates that zfs should make
4149 inherit the key of its parent. Note that this command can only be run on an
4150 encryption root that has an encrypted parent.
4156 utility exits 0 on success, 1 if an error occurs, and 2 if invalid command line
4157 options were specified.
4160 .It Sy Example 1 No Creating a ZFS File System Hierarchy
4161 The following commands create a file system named
4163 and a file system named
4167 is set for the parent file system, and is automatically inherited by the child
4170 # zfs create pool/home
4171 # zfs set mountpoint=/export/home pool/home
4172 # zfs create pool/home/bob
4174 .It Sy Example 2 No Creating a ZFS Snapshot
4175 The following command creates a snapshot named
4177 This snapshot is mounted on demand in the
4179 directory at the root of the
4183 # zfs snapshot pool/home/bob@yesterday
4185 .It Sy Example 3 No Creating and Destroying Multiple Snapshots
4186 The following command creates snapshots named
4190 and all of its descendent file systems.
4191 Each snapshot is mounted on demand in the
4193 directory at the root of its file system.
4194 The second command destroys the newly created snapshots.
4196 # zfs snapshot -r pool/home@yesterday
4197 # zfs destroy -r pool/home@yesterday
4199 .It Sy Example 4 No Disabling and Enabling File System Compression
4200 The following command disables the
4202 property for all file systems under
4204 The next command explicitly enables
4207 .Em pool/home/anne .
4209 # zfs set compression=off pool/home
4210 # zfs set compression=on pool/home/anne
4212 .It Sy Example 5 No Listing ZFS Datasets
4213 The following command lists all active file systems and volumes in the system.
4214 Snapshots are displayed if the
4222 for more information on pool properties.
4225 NAME USED AVAIL REFER MOUNTPOINT
4226 pool 450K 457G 18K /pool
4227 pool/home 315K 457G 21K /export/home
4228 pool/home/anne 18K 457G 18K /export/home/anne
4229 pool/home/bob 276K 457G 276K /export/home/bob
4231 .It Sy Example 6 No Setting a Quota on a ZFS File System
4232 The following command sets a quota of 50 Gbytes for
4235 # zfs set quota=50G pool/home/bob
4237 .It Sy Example 7 No Listing ZFS Properties
4238 The following command lists all properties for
4241 # zfs get all pool/home/bob
4242 NAME PROPERTY VALUE SOURCE
4243 pool/home/bob type filesystem -
4244 pool/home/bob creation Tue Jul 21 15:53 2009 -
4245 pool/home/bob used 21K -
4246 pool/home/bob available 20.0G -
4247 pool/home/bob referenced 21K -
4248 pool/home/bob compressratio 1.00x -
4249 pool/home/bob mounted yes -
4250 pool/home/bob quota 20G local
4251 pool/home/bob reservation none default
4252 pool/home/bob recordsize 128K default
4253 pool/home/bob mountpoint /pool/home/bob default
4254 pool/home/bob sharenfs off default
4255 pool/home/bob checksum on default
4256 pool/home/bob compression on local
4257 pool/home/bob atime on default
4258 pool/home/bob devices on default
4259 pool/home/bob exec on default
4260 pool/home/bob setuid on default
4261 pool/home/bob readonly off default
4262 pool/home/bob zoned off default
4263 pool/home/bob snapdir hidden default
4264 pool/home/bob acltype off default
4265 pool/home/bob aclinherit restricted default
4266 pool/home/bob canmount on default
4267 pool/home/bob xattr on default
4268 pool/home/bob copies 1 default
4269 pool/home/bob version 4 -
4270 pool/home/bob utf8only off -
4271 pool/home/bob normalization none -
4272 pool/home/bob casesensitivity sensitive -
4273 pool/home/bob vscan off default
4274 pool/home/bob nbmand off default
4275 pool/home/bob sharesmb off default
4276 pool/home/bob refquota none default
4277 pool/home/bob refreservation none default
4278 pool/home/bob primarycache all default
4279 pool/home/bob secondarycache all default
4280 pool/home/bob usedbysnapshots 0 -
4281 pool/home/bob usedbydataset 21K -
4282 pool/home/bob usedbychildren 0 -
4283 pool/home/bob usedbyrefreservation 0 -
4286 The following command gets a single property value.
4288 # zfs get -H -o value compression pool/home/bob
4291 The following command lists all properties with local settings for
4294 # zfs get -r -s local -o name,property,value all pool/home/bob
4296 pool/home/bob quota 20G
4297 pool/home/bob compression on
4299 .It Sy Example 8 No Rolling Back a ZFS File System
4300 The following command reverts the contents of
4302 to the snapshot named
4304 deleting all intermediate snapshots.
4306 # zfs rollback -r pool/home/anne@yesterday
4308 .It Sy Example 9 No Creating a ZFS Clone
4309 The following command creates a writable file system whose initial contents are
4311 .Em pool/home/bob@yesterday .
4313 # zfs clone pool/home/bob@yesterday pool/clone
4315 .It Sy Example 10 No Promoting a ZFS Clone
4316 The following commands illustrate how to test out changes to a file system, and
4317 then replace the original file system with the changed one, using clones, clone
4318 promotion, and renaming:
4320 # zfs create pool/project/production
4321 populate /pool/project/production with data
4322 # zfs snapshot pool/project/production@today
4323 # zfs clone pool/project/production@today pool/project/beta
4324 make changes to /pool/project/beta and test them
4325 # zfs promote pool/project/beta
4326 # zfs rename pool/project/production pool/project/legacy
4327 # zfs rename pool/project/beta pool/project/production
4328 once the legacy version is no longer needed, it can be destroyed
4329 # zfs destroy pool/project/legacy
4331 .It Sy Example 11 No Inheriting ZFS Properties
4332 The following command causes
4338 property from their parent.
4340 # zfs inherit checksum pool/home/bob pool/home/anne
4342 .It Sy Example 12 No Remotely Replicating ZFS Data
4343 The following commands send a full stream and then an incremental stream to a
4344 remote machine, restoring them into
4345 .Em poolB/received/fs@a
4347 .Em poolB/received/fs@b ,
4350 must contain the file system
4351 .Em poolB/received ,
4352 and must not initially contain
4353 .Em poolB/received/fs .
4355 # zfs send pool/fs@a | \e
4356 ssh host zfs receive poolB/received/fs@a
4357 # zfs send -i a pool/fs@b | \e
4358 ssh host zfs receive poolB/received/fs
4360 .It Sy Example 13 No Using the zfs receive -d Option
4361 The following command sends a full stream of
4362 .Em poolA/fsA/fsB@snap
4363 to a remote machine, receiving it into
4364 .Em poolB/received/fsA/fsB@snap .
4367 portion of the received snapshot's name is determined from the name of the sent
4370 must contain the file system
4371 .Em poolB/received .
4373 .Em poolB/received/fsA
4374 does not exist, it is created as an empty file system.
4376 # zfs send poolA/fsA/fsB@snap | \e
4377 ssh host zfs receive -d poolB/received
4379 .It Sy Example 14 No Setting User Properties
4380 The following example sets the user-defined
4381 .Sy com.example:department
4382 property for a dataset.
4384 # zfs set com.example:department=12345 tank/accounting
4386 .It Sy Example 15 No Performing a Rolling Snapshot
4387 The following example shows how to maintain a history of snapshots with a
4388 consistent naming scheme.
4389 To keep a week's worth of snapshots, the user destroys the oldest snapshot,
4390 renames the remaining snapshots, and then creates a new snapshot, as follows:
4392 # zfs destroy -r pool/users@7daysago
4393 # zfs rename -r pool/users@6daysago @7daysago
4394 # zfs rename -r pool/users@5daysago @6daysago
4395 # zfs rename -r pool/users@yesterday @5daysago
4396 # zfs rename -r pool/users@yesterday @4daysago
4397 # zfs rename -r pool/users@yesterday @3daysago
4398 # zfs rename -r pool/users@yesterday @2daysago
4399 # zfs rename -r pool/users@today @yesterday
4400 # zfs snapshot -r pool/users@today
4402 .It Sy Example 16 No Setting sharenfs Property Options on a ZFS File System
4403 The following commands show how to set
4405 property options to enable
4409 addresses and to enable root access for system
4415 # zfs set sharenfs='rw=@123.123.0.0/16,root=neo' tank/home
4420 for host name resolution, specify the fully qualified hostname.
4421 .It Sy Example 17 No Delegating ZFS Administration Permissions on a ZFS Dataset
4422 The following example shows how to set permissions so that user
4424 can create, destroy, mount, and take snapshots on
4430 # zfs allow cindys create,destroy,mount,snapshot tank/cindys
4431 # zfs allow tank/cindys
4432 ---- Permissions on tank/cindys --------------------------------------
4433 Local+Descendent permissions:
4434 user cindys create,destroy,mount,snapshot
4439 mount point permission is set to 755 by default, user
4441 will be unable to mount file systems under
4443 Add an ACE similar to the following syntax to provide mount point access:
4445 # chmod A+user:cindys:add_subdirectory:allow /tank/cindys
4447 .It Sy Example 18 No Delegating Create Time Permissions on a ZFS Dataset
4448 The following example shows how to grant anyone in the group
4450 to create file systems in
4452 This syntax also allows staff members to destroy their own file systems, but not
4453 destroy anyone else's file system.
4458 # zfs allow staff create,mount tank/users
4459 # zfs allow -c destroy tank/users
4460 # zfs allow tank/users
4461 ---- Permissions on tank/users ---------------------------------------
4464 Local+Descendent permissions:
4465 group staff create,mount
4467 .It Sy Example 19 No Defining and Granting a Permission Set on a ZFS Dataset
4468 The following example shows how to define and grant a permission set on the
4475 # zfs allow -s @pset create,destroy,snapshot,mount tank/users
4476 # zfs allow staff @pset tank/users
4477 # zfs allow tank/users
4478 ---- Permissions on tank/users ---------------------------------------
4480 @pset create,destroy,mount,snapshot
4481 Local+Descendent permissions:
4484 .It Sy Example 20 No Delegating Property Permissions on a ZFS Dataset
4485 The following example shows to grant the ability to set quotas and reservations
4493 # zfs allow cindys quota,reservation users/home
4494 # zfs allow users/home
4495 ---- Permissions on users/home ---------------------------------------
4496 Local+Descendent permissions:
4497 user cindys quota,reservation
4498 cindys% zfs set quota=10G users/home/marks
4499 cindys% zfs get quota users/home/marks
4500 NAME PROPERTY VALUE SOURCE
4501 users/home/marks quota 10G local
4503 .It Sy Example 21 No Removing ZFS Delegated Permissions on a ZFS Dataset
4504 The following example shows how to remove the snapshot permission from the
4513 # zfs unallow staff snapshot tank/users
4514 # zfs allow tank/users
4515 ---- Permissions on tank/users ---------------------------------------
4517 @pset create,destroy,mount,snapshot
4518 Local+Descendent permissions:
4521 .It Sy Example 22 No Showing the differences between a snapshot and a ZFS Dataset
4522 The following example shows how to see what has changed between a prior
4523 snapshot of a ZFS dataset and its current state.
4526 option is used to indicate type information for the files affected.
4528 # zfs diff -F tank/test@before tank/test
4530 M F /tank/test/linked (+1)
4531 R F /tank/test/oldname -> /tank/test/newname
4532 - F /tank/test/deleted
4533 + F /tank/test/created
4534 M F /tank/test/modified
4536 .It Sy Example 23 No Creating a bookmark
4537 The following example create a bookmark to a snapshot. This bookmark
4538 can then be used instead of snapshot in send streams.
4540 # zfs bookmark rpool@snapshot rpool#bookmark
4542 .It Sy Example 24 No Setting sharesmb Property Options on a ZFS File System
4543 The following example show how to share SMB filesystem through ZFS. Note that
4544 that a user and his/her password must be given.
4546 # smbmount //127.0.0.1/share_tmp /mnt/tmp \\
4547 -o user=workgroup/turbo,password=obrut,uid=1000
4551 .Em /etc/samba/smb.conf
4552 configuration required:
4554 Samba will need to listen to 'localhost' (127.0.0.1) for the ZFS utilities to
4555 communicate with Samba. This is the default behavior for most Linux
4558 Samba must be able to authenticate a user. This can be done in a number of
4559 ways, depending on if using the system password file, LDAP or the Samba
4560 specific smbpasswd file. How to do this is outside the scope of this manual.
4563 man page for more information.
4566 .Sy USERSHARE section
4569 man page for all configuration options in case you need to modify any options
4570 to the share afterwards. Do note that any changes done with the
4572 command will be undone if the share is ever unshared (such as at a reboot etc).
4574 .Sh INTERFACE STABILITY
projects / zfs / blob