xref: /titanic_51/usr/src/man/man1m/zfs.1m (revision b60ae21d2303cc238394b46cddb93a2dbcdb2e07)
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22.\" Copyright (c) 2009 Sun Microsystems, Inc. All Rights Reserved.
23.\" Copyright 2011 Joshua M. Clulow <josh@sysmgr.org>
24.\" Copyright (c) 2011, 2015 by Delphix. All rights reserved.
25.\" Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
26.\" Copyright (c) 2014, Joyent, Inc. All rights reserved.
27.\" Copyright (c) 2014 by Adam Stevko. All rights reserved.
28.\" Copyright 2015 Nexenta Systems, Inc.  All Rights Reserved.
29.\" Copyright (c) 2014 Integros [integros.com]
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31.Dd September 16, 2016
32.Dt ZFS 1M
33.Os
34.Sh NAME
35.Nm zfs
36.Nd configures ZFS file systems
37.Sh SYNOPSIS
38.Nm
39.Op Fl \?
40.Nm
41.Cm create
42.Op Fl p
43.Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
44.Ar filesystem
45.Nm
46.Cm create
47.Op Fl ps
48.Op Fl b Ar blocksize
49.Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
50.Fl V Ar size Ar volume
51.Nm
52.Cm destroy
53.Op Fl Rfnprv
54.Ar filesystem Ns | Ns Ar volume
55.Nm
56.Cm destroy
57.Op Fl Rdnprv
58.Ar filesystem Ns | Ns Ar volume Ns @ Ns Ar snap Ns
59.Oo % Ns Ar snap Ns Oo , Ns Ar snap Ns Oo % Ns Ar snap Oc Oc Oc Ns ...
60.Nm
61.Cm destroy
62.Ar filesystem Ns | Ns Ar volume Ns # Ns Ar bookmark
63.Nm
64.Cm snapshot
65.Op Fl r
66.Oo Fl o Ar property Ns = Ns value Oc Ns ...
67.Ar filesystem Ns @ Ns Ar snapname Ns | Ns Ar volume Ns @ Ns Ar snapname Ns ...
68.Nm
69.Cm rollback
70.Op Fl Rfr
71.Ar snapshot
72.Nm
73.Cm clone
74.Op Fl p
75.Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
76.Ar snapshot Ar filesystem Ns | Ns Ar volume
77.Nm
78.Cm promote
79.Ar clone-filesystem
80.Nm
81.Cm rename
82.Op Fl f
83.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
84.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
85.Nm
86.Cm rename
87.Op Fl fp
88.Ar filesystem Ns | Ns Ar volume
89.Ar filesystem Ns | Ns Ar volume
90.Nm
91.Cm rename
92.Fl r
93.Ar snapshot Ar snapshot
94.Nm
95.Cm list
96.Op Fl r Ns | Ns Fl d Ar depth
97.Op Fl Hp
98.Oo Fl o Ar property Ns Oo , Ns Ar property Oc Ns ... Oc
99.Oo Fl s Ar property Oc Ns ...
100.Oo Fl S Ar property Oc Ns ...
101.Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
102.Oo Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Oc Ns ...
103.Nm
104.Cm set
105.Ar property Ns = Ns Ar value Oo Ar property Ns = Ns Ar value Oc Ns ...
106.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
107.Nm
108.Cm get
109.Op Fl r Ns | Ns Fl d Ar depth
110.Op Fl Hp
111.Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
112.Oo Fl s Ar source Ns Oo , Ns Ar source Oc Ns ... Oc
113.Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
114.Cm all | Ar property Ns Oo , Ns Ar property Oc Ns ...
115.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns | Ns Ar bookmark Ns ...
116.Nm
117.Cm inherit
118.Op Fl rS
119.Ar property Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
120.Nm
121.Cm upgrade
122.Nm
123.Cm upgrade
124.Fl v
125.Nm
126.Cm upgrade
127.Op Fl r
128.Op Fl V Ar version
129.Fl a | Ar filesystem
130.Nm
131.Cm userspace
132.Op Fl Hinp
133.Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
134.Oo Fl s Ar field Oc Ns ...
135.Oo Fl S Ar field Oc Ns ...
136.Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
137.Ar filesystem Ns | Ns Ar snapshot
138.Nm
139.Cm groupspace
140.Op Fl Hinp
141.Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
142.Oo Fl s Ar field Oc Ns ...
143.Oo Fl S Ar field Oc Ns ...
144.Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
145.Ar filesystem Ns | Ns Ar snapshot
146.Nm
147.Cm mount
148.Nm
149.Cm mount
150.Op Fl Ov
151.Op Fl o Ar options
152.Fl a | Ar filesystem
153.Nm
154.Cm unmount
155.Op Fl f
156.Fl a | Ar filesystem Ns | Ns Ar mountpoint
157.Nm
158.Cm share
159.Fl a | Ar filesystem
160.Nm
161.Cm unshare
162.Fl a | Ar filesystem Ns | Ns Ar mountpoint
163.Nm
164.Cm bookmark
165.Ar snapshot bookmark
166.Nm
167.Cm send
168.Op Fl DLPRenpv
169.Op Oo Fl I Ns | Ns Fl i Oc Ar snapshot
170.Ar snapshot
171.Nm
172.Cm send
173.Op Fl Le
174.Op Fl i Ar snapshot Ns | Ns Ar bookmark
175.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
176.Nm
177.Cm send
178.Op Fl Penv
179.Fl t Ar receive_resume_token
180.Nm
181.Cm receive
182.Op Fl Fnsuv
183.Op Fl o Sy origin Ns = Ns Ar snapshot
184.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
185.Nm
186.Cm receive
187.Op Fl Fnsuv
188.Op Fl d Ns | Ns Fl e
189.Op Fl o Sy origin Ns = Ns Ar snapshot
190.Ar filesystem
191.Nm
192.Cm receive
193.Fl A
194.Ar filesystem Ns | Ns Ar volume
195.Nm
196.Cm allow
197.Ar filesystem Ns | Ns Ar volume
198.Nm
199.Cm allow
200.Op Fl dglu
201.Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
202.Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
203.Ar setname Oc Ns ...
204.Ar filesystem Ns | Ns Ar volume
205.Nm
206.Cm allow
207.Op Fl dl
208.Fl e Ns | Ns Sy everyone
209.Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
210.Ar setname Oc Ns ...
211.Ar filesystem Ns | Ns Ar volume
212.Nm
213.Cm allow
214.Fl c
215.Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
216.Ar setname Oc Ns ...
217.Ar filesystem Ns | Ns Ar volume
218.Nm
219.Cm allow
220.Fl s No @ Ns Ar setname
221.Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
222.Ar setname Oc Ns ...
223.Ar filesystem Ns | Ns Ar volume
224.Nm
225.Cm unallow
226.Op Fl dglru
227.Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
228.Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
229.Ar setname Oc Ns ... Oc
230.Ar filesystem Ns | Ns Ar volume
231.Nm
232.Cm unallow
233.Op Fl dlr
234.Fl e Ns | Ns Sy everyone
235.Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
236.Ar setname Oc Ns ... Oc
237.Ar filesystem Ns | Ns Ar volume
238.Nm
239.Cm unallow
240.Op Fl r
241.Fl c
242.Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
243.Ar setname Oc Ns ... Oc
244.Ar filesystem Ns | Ns Ar volume
245.Nm
246.Cm unallow
247.Op Fl r
248.Fl s @ Ns Ar setname
249.Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
250.Ar setname Oc Ns ... Oc
251.Ar filesystem Ns | Ns Ar volume
252.Nm
253.Cm hold
254.Op Fl r
255.Ar tag Ar snapshot Ns ...
256.Nm
257.Cm holds
258.Op Fl r
259.Ar snapshot Ns ...
260.Nm
261.Cm release
262.Op Fl r
263.Ar tag Ar snapshot Ns ...
264.Nm
265.Cm diff
266.Op Fl FHt
267.Ar snapshot Ar snapshot Ns | Ns Ar filesystem
268.Sh DESCRIPTION
269The
270.Nm
271command configures ZFS datasets within a ZFS storage pool, as described in
272.Xr zpool 1M .
273A dataset is identified by a unique path within the ZFS namespace. For example:
274.Bd -literal
275pool/{filesystem,volume,snapshot}
276.Ed
277.Pp
278where the maximum length of a dataset name is
279.Dv MAXNAMELEN
280.Pq 256 bytes .
281.Pp
282A dataset can be one of the following:
283.Bl -tag -width "file system"
284.It Sy file system
285A ZFS dataset of type
286.Sy filesystem
287can be mounted within the standard system namespace and behaves like other file
288systems. While ZFS file systems are designed to be POSIX compliant, known issues
289exist that prevent compliance in some cases. Applications that depend on
290standards conformance might fail due to non-standard behavior when checking file
291system free space.
292.It Sy volume
293A logical volume exported as a raw or block device. This type of dataset should
294only be used under special circumstances. File systems are typically used in
295most environments.
296.It Sy snapshot
297A read-only version of a file system or volume at a given point in time. It is
298specified as
299.Ar filesystem Ns @ Ns Ar name
300or
301.Ar volume Ns @ Ns Ar name .
302.El
303.Ss ZFS File System Hierarchy
304A ZFS storage pool is a logical collection of devices that provide space for
305datasets. A storage pool is also the root of the ZFS file system hierarchy.
306.Pp
307The root of the pool can be accessed as a file system, such as mounting and
308unmounting, taking snapshots, and setting properties. The physical storage
309characteristics, however, are managed by the
310.Xr zpool 1M
311command.
312.Pp
313See
314.Xr zpool 1M
315for more information on creating and administering pools.
316.Ss Snapshots
317A snapshot is a read-only copy of a file system or volume. Snapshots can be
318created extremely quickly, and initially consume no additional space within the
319pool. As data within the active dataset changes, the snapshot consumes more
320data than would otherwise be shared with the active dataset.
321.Pp
322Snapshots can have arbitrary names. Snapshots of volumes can be cloned or
323rolled back, but cannot be accessed independently.
324.Pp
325File system snapshots can be accessed under the
326.Pa .zfs/snapshot
327directory in the root of the file system. Snapshots are automatically mounted on
328demand and may be unmounted at regular intervals. The visibility of the
329.Pa .zfs
330directory can be controlled by the
331snapdir
332property.
333.Ss Clones
334A clone is a writable volume or file system whose initial contents are the same
335as another dataset. As with snapshots, creating a clone is nearly instantaneous,
336and initially consumes no additional space.
337.Pp
338Clones can only be created from a snapshot. When a snapshot is cloned, it
339creates an implicit dependency between the parent and child. Even though the
340clone is created somewhere else in the dataset hierarchy, the original snapshot
341cannot be destroyed as long as a clone exists. The
342.Sy origin
343property exposes this dependency, and the
344.Cm destroy
345command lists any such dependencies, if they exist.
346.Pp
347The clone parent-child dependency relationship can be reversed by using the
348.Cm promote
349subcommand. This causes the
350.Qq origin
351file system to become a clone of the specified file system, which makes it
352possible to destroy the file system that the clone was created from.
353.Ss "Mount Points"
354Creating a ZFS file system is a simple operation, so the number of file systems
355per system is likely to be numerous. To cope with this, ZFS automatically
356manages mounting and unmounting file systems without the need to edit the
357.Pa /etc/vfstab
358file. All automatically managed file systems are mounted by ZFS at boot time.
359.Pp
360By default, file systems are mounted under
361.Pa /path ,
362where
363.Ar path
364is the name of the file system in the ZFS namespace. Directories are created and
365destroyed as needed.
366.Pp
367A file system can also have a mount point set in the
368.Sy mountpoint
369property. This directory is created as needed, and ZFS automatically mounts the
370file system when the
371.Nm zfs Cm mount Fl a
372command is invoked
373.Po without editing
374.Pa /etc/vfstab
375.Pc .
376The
377.Sy mountpoint
378property can be inherited, so if
379.Em pool/home
380has a mount point of
381.Pa /export/stuff ,
382then
383.Em pool/home/user
384automatically inherits a mount point of
385.Pa /export/stuff/user .
386.Pp
387A file system
388.Sy mountpoint
389property of
390.Sy none
391prevents the file system from being mounted.
392.Pp
393If needed, ZFS file systems can also be managed with traditional tools
394.Po
395.Nm mount ,
396.Nm umount ,
397.Pa /etc/vfstab
398.Pc .
399If a file system's mount point is set to
400.Sy legacy ,
401ZFS makes no attempt to manage the file system, and the administrator is
402responsible for mounting and unmounting the file system.
403.Ss "Zones"
404A ZFS file system can be added to a non-global zone by using the
405.Nm zonecfg Cm add Sy fs
406subcommand. A ZFS file system that is added to a non-global zone must have its
407.Sy mountpoint
408property set to
409.Sy legacy .
410.Pp
411The physical properties of an added file system are controlled by the global
412administrator. However, the zone administrator can create, modify, or destroy
413files within the added file system, depending on how the file system is mounted.
414.Pp
415A dataset can also be delegated to a non-global zone by using the
416.Nm zonecfg Cm add Sy dataset
417subcommand. You cannot delegate a dataset to one zone and the children of the
418same dataset to another zone. The zone administrator can change properties of
419the dataset or any of its children. However, the
420.Sy quota ,
421.Sy filesystem_limit
422and
423.Sy snapshot_limit
424properties of the delegated dataset can be modified only by the global
425administrator.
426.Pp
427A ZFS volume can be added as a device to a non-global zone by using the
428.Nm zonecfg Cm add Sy device
429subcommand. However, its physical properties can be modified only by the global
430administrator.
431.Pp
432For more information about
433.Nm zonecfg
434syntax, see
435.Xr zonecfg 1M .
436.Pp
437After a dataset is delegated to a non-global zone, the
438.Sy zoned
439property is automatically set. A zoned file system cannot be mounted in the
440global zone, since the zone administrator might have to set the mount point to
441an unacceptable value.
442.Pp
443The global administrator can forcibly clear the
444.Sy zoned
445property, though this should be done with extreme care. The global administrator
446should verify that all the mount points are acceptable before clearing the
447property.
448.Ss Native Properties
449Properties are divided into two types, native properties and user-defined
450.Po or
451.Qq user
452.Pc
453properties. Native properties either export internal statistics or control ZFS
454behavior. In addition, native properties are either editable or read-only. User
455properties have no effect on ZFS behavior, but you can use them to annotate
456datasets in a way that is meaningful in your environment. For more information
457about user properties, see the
458.Sx User Properties
459section, below.
460.Pp
461Every dataset has a set of properties that export statistics about the dataset
462as well as control various behaviors. Properties are inherited from the parent
463unless overridden by the child. Some properties apply only to certain types of
464datasets
465.Pq file systems, volumes, or snapshots .
466.Pp
467The values of numeric properties can be specified using human-readable suffixes
468.Po for example,
469.Sy k ,
470.Sy KB ,
471.Sy M ,
472.Sy Gb ,
473and so forth, up to
474.Sy Z
475for zettabyte
476.Pc .
477The following are all valid
478.Pq and equal
479specifications:
480.Li 1536M, 1.5g, 1.50GB .
481.Pp
482The values of non-numeric properties are case sensitive and must be lowercase,
483except for
484.Sy mountpoint ,
485.Sy sharenfs ,
486and
487.Sy sharesmb .
488.Pp
489The following native properties consist of read-only statistics about the
490dataset. These properties can be neither set, nor inherited. Native properties
491apply to all dataset types unless otherwise noted.
492.Bl -tag -width "usedbyrefreservation"
493.It Sy available
494The amount of space available to the dataset and all its children, assuming that
495there is no other activity in the pool. Because space is shared within a pool,
496availability can be limited by any number of factors, including physical pool
497size, quotas, reservations, or other datasets within the pool.
498.Pp
499This property can also be referred to by its shortened column name,
500.Sy avail .
501.It Sy compressratio
502For non-snapshots, the compression ratio achieved for the
503.Sy used
504space of this dataset, expressed as a multiplier. The
505.Sy used
506property includes descendant datasets, and, for clones, does not include the
507space shared with the origin snapshot. For snapshots, the
508.Sy compressratio
509is the same as the
510.Sy refcompressratio
511property. Compression can be turned on by running:
512.Nm zfs Cm set Sy compression Ns = Ns Sy on Ar dataset .
513The default value is
514.Sy off .
515.It Sy creation
516The time this dataset was created.
517.It Sy clones
518For snapshots, this property is a comma-separated list of filesystems or volumes
519which are clones of this snapshot. The clones'
520.Sy origin
521property is this snapshot. If the
522.Sy clones
523property is not empty, then this snapshot can not be destroyed
524.Po even with the
525.Fl r
526or
527.Fl f
528options
529.Pc .
530.It Sy defer_destroy
531This property is
532.Sy on
533if the snapshot has been marked for deferred destroy by using the
534.Nm zfs Cm destroy Fl d
535command. Otherwise, the property is
536.Sy off .
537.It Sy filesystem_count
538The total number of filesystems and volumes that exist under this location in
539the dataset tree. This value is only available when a
540.Sy filesystem_limit
541has been set somewhere in the tree under which the dataset resides.
542.It Sy logicalreferenced
543The amount of space that is
544.Qq logically
545accessible by this dataset. See the
546.Sy referenced
547property. The logical space ignores the effect of the
548.Sy compression
549and
550.Sy copies
551properties, giving a quantity closer to the amount of data that applications
552see. However, it does include space consumed by metadata.
553.Pp
554This property can also be referred to by its shortened column name,
555.Sy lrefer .
556.It Sy logicalused
557The amount of space that is
558.Qq logically
559consumed by this dataset and all its descendents. See the
560.Sy used
561property. The logical space ignores the effect of the
562.Sy compression
563and
564.Sy copies
565properties, giving a quantity closer to the amount of data that applications
566see. However, it does include space consumed by metadata.
567.Pp
568This property can also be referred to by its shortened column name,
569.Sy lused .
570.It Sy mounted
571For file systems, indicates whether the file system is currently mounted. This
572property can be either
573.Sy yes
574or
575.Sy no .
576.It Sy origin
577For cloned file systems or volumes, the snapshot from which the clone was
578created. See also the
579.Sy clones
580property.
581.It Sy receive_resume_token
582For filesystems or volumes which have saved partially-completed state from
583.Sy zfs receive -s ,
584this opaque token can be provided to
585.Sy zfs send -t
586to resume and complete the
587.Sy zfs receive .
588.It Sy referenced
589The amount of data that is accessible by this dataset, which may or may not be
590shared with other datasets in the pool. When a snapshot or clone is created, it
591initially references the same amount of space as the file system or snapshot it
592was created from, since its contents are identical.
593.Pp
594This property can also be referred to by its shortened column name,
595.Sy refer .
596.It Sy refcompressratio
597The compression ratio achieved for the
598.Sy referenced
599space of this dataset, expressed as a multiplier. See also the
600.Sy compressratio
601property.
602.It Sy snapshot_count
603The total number of snapshots that exist under this location in the dataset
604tree. This value is only available when a
605.Sy snapshot_limit
606has been set somewhere in the tree under which the dataset resides.
607.It Sy type
608The type of dataset:
609.Sy filesystem ,
610.Sy volume ,
611or
612.Sy snapshot .
613.It Sy used
614The amount of space consumed by this dataset and all its descendents. This is
615the value that is checked against this dataset's quota and reservation. The
616space used does not include this dataset's reservation, but does take into
617account the reservations of any descendent datasets. The amount of space that a
618dataset consumes from its parent, as well as the amount of space that are freed
619if this dataset is recursively destroyed, is the greater of its space used and
620its reservation.
621.Pp
622When snapshots
623.Po see the
624.Sx Snapshots
625section
626.Pc
627are created, their space is initially shared between the snapshot and
628the file system, and possibly with previous snapshots. As the file system
629changes, space that was previously shared becomes unique to the snapshot, and
630counted in the snapshot's space used. Additionally, deleting snapshots can
631increase the amount of space unique to
632.Pq and used by
633other snapshots.
634.Pp
635The amount of space used, available, or referenced does not take into account
636pending changes. Pending changes are generally accounted for within a few
637seconds. Committing a change to a disk using
638.Xr fsync 3C
639or
640.Dv O_SYNC
641does not necessarily guarantee that the space usage information is updated
642immediately.
643.It Sy usedby*
644The
645.Sy usedby*
646properties decompose the
647.Sy used
648properties into the various reasons that space is used. Specifically,
649.Sy used No =
650.Sy usedbychildren No +
651.Sy usedbydataset No +
652.Sy usedbyrefreservation No +
653.Sy usedbysnapshots .
654These properties are only available for datasets created on
655.Nm zpool
656.Qo version 13 Qc
657pools.
658.It Sy usedbychildren
659The amount of space used by children of this dataset, which would be freed if
660all the dataset's children were destroyed.
661.It Sy usedbydataset
662The amount of space used by this dataset itself, which would be freed if the
663dataset were destroyed
664.Po after first removing any
665.Sy refreservation
666and destroying any necessary snapshots or descendents
667.Pc .
668.It Sy usedbyrefreservation
669The amount of space used by a
670.Sy refreservation
671set on this dataset, which would be freed if the
672.Sy refreservation
673was removed.
674.It Sy usedbysnapshots
675The amount of space consumed by snapshots of this dataset. In particular, it is
676the amount of space that would be freed if all of this dataset's snapshots were
677destroyed. Note that this is not simply the sum of the snapshots'
678.Sy used
679properties because space can be shared by multiple snapshots.
680.It Sy userused Ns @ Ns Em user
681The amount of space consumed by the specified user in this dataset. Space is
682charged to the owner of each file, as displayed by
683.Nm ls Fl l .
684The amount of space charged is displayed by
685.Nm du
686and
687.Nm ls Fl s .
688See the
689.Nm zfs Cm userspace
690subcommand for more information.
691.Pp
692Unprivileged users can access only their own space usage. The root user, or a
693user who has been granted the
694.Sy userused
695privilege with
696.Nm zfs Cm allow ,
697can access everyone's usage.
698.Pp
699The
700.Sy userused Ns @ Ns Em ...
701properties are not displayed by
702.Nm zfs Cm get Sy all .
703The user's name must be appended after the @ symbol, using one of the following
704forms:
705.Bl -bullet -width ""
706.It
707.Em POSIX name
708.Po for example,
709.Sy joe
710.Pc
711.It
712.Em POSIX numeric ID
713.Po for example,
714.Sy 789
715.Pc
716.It
717.Em SID name
718.Po for example,
719.Sy joe.smith@mydomain
720.Pc
721.It
722.Em SID numeric ID
723.Po for example,
724.Sy S-1-123-456-789
725.Pc
726.El
727.It Sy userrefs
728This property is set to the number of user holds on this snapshot. User holds
729are set by using the
730.Nm zfs Cm hold
731command.
732.It Sy groupused Ns @ Ns Em group
733The amount of space consumed by the specified group in this dataset. Space is
734charged to the group of each file, as displayed by
735.Nm ls Fl l .
736See the
737.Sy userused Ns @ Ns Em user
738property for more information.
739.Pp
740Unprivileged users can only access their own groups' space usage. The root user,
741or a user who has been granted the
742.Sy groupused
743privilege with
744.Nm zfs Cm allow ,
745can access all groups' usage.
746.It Sy volblocksize Ns = Ns Em blocksize
747For volumes, specifies the block size of the volume. The
748.Sy blocksize
749cannot be changed once the volume has been written, so it should be set at
750volume creation time. The default
751.Sy blocksize
752for volumes is 8 Kbytes. Any power of 2 from 512 bytes to 128 Kbytes is valid.
753.Pp
754This property can also be referred to by its shortened column name,
755.Sy volblock .
756.It Sy written
757The amount of
758.Sy referenced
759space written to this dataset since the previous snapshot.
760.It Sy written Ns @ Ns Em snapshot
761The amount of
762.Sy referenced
763space written to this dataset since the specified snapshot. This is the space
764that is referenced by this dataset but was not referenced by the specified
765snapshot.
766.Pp
767The
768.Em snapshot
769may be specified as a short snapshot name
770.Po just the part after the
771.Sy @
772.Pc ,
773in which case it will be interpreted as a snapshot in the same filesystem as
774this dataset. The
775.Em snapshot
776may be a full snapshot name
777.Po Em filesystem Ns @ Ns Em snapshot Pc ,
778which for clones may be a snapshot in the origin's filesystem
779.Pq or the origin of the origin's filesystem, etc.
780.El
781.Pp
782The following native properties can be used to change the behavior of a ZFS
783dataset.
784.Bl -tag -width ""
785.It Xo
786.Sy aclinherit Ns = Ns Sy discard Ns | Ns Sy noallow Ns | Ns
787.Sy restricted Ns | Ns Sy passthrough Ns | Ns Sy passthrough-x
788.Xc
789Controls how
790.Sy ACE Ns s
791are inherited when files and directories are created.
792.Bl -tag -width "passthrough-x"
793.It Sy discard
794does not inherit any
795.Sy ACE Ns s .
796.It Sy noallow
797only inherits inheritable
798.Sy ACE Ns s
799that specify
800.Qq deny
801permissions.
802.It Sy restricted
803default, removes the
804.Sy write_acl
805and
806.Sy write_owner
807permissions when the
808.Sy ACE
809is inherited.
810.It Sy passthrough
811inherits all inheritable
812.Sy ACE Ns s
813without any modifications.
814.It Sy passthrough-x
815same meaning as
816.Sy passthrough ,
817except that the
818.Sy owner@ ,
819.Sy group@ ,
820and
821.Sy everyone@
822.Sy ACE Ns s
823inherit the execute permission only if the file creation mode also requests the
824execute bit.
825.El
826.Pp
827When the property value is set to
828.Sy passthrough ,
829files are created with a mode determined by the inheritable
830.Sy ACE Ns s .
831If no inheritable
832.Sy ACE Ns s
833exist that affect the mode, then the mode is set in accordance to the requested
834mode from the application.
835.It Xo
836.Sy aclmode Ns = Ns Sy discard Ns | Ns Sy groupmask Ns | Ns
837.Sy passthrough Ns | Ns Sy restricted
838.Xc
839Controls how an
840.Sy ACL
841is modified during
842.Xr chmod 2 .
843.Bl -tag -width "passthrough"
844.It Sy discard
845default, deletes all
846.Sy ACE Ns s
847that do not represent the mode of the file.
848.It Sy groupmask
849reduces permissions granted in all
850.Sy ALLOW
851entries found in the
852.Sy ACL
853such that they are no greater than the group permissions specified by
854.Xr chmod 2 .
855.It Sy passthrough
856indicates that no changes are made to the
857.Sy ACL
858other than creating or updating the necessary
859.Sy ACE Ns s
860to represent the new mode of the file or directory.
861.It Sy restricted
862causes the
863.Xr chmod 2
864operation to return an error when used on any file or directory which has a
865non-trivial
866.Sy ACE Ns s
867whose entries can not be represented by a mode.
868.El
869.Pp
870.Xr chmod 2
871is required to change the set user ID, set group ID, or sticky bits on a file or
872directory, as they do not have equivalent
873.Sy ACE Ns s.
874In order to use
875.Xr chmod 2
876on a file or directory with a non-trivial
877.Sy ACL
878when
879.Sy aclmode
880is set to
881.Sy restricted ,
882you must first remove all
883.Sy ACE Ns s
884which do not represent the current mode.
885.It Sy atime Ns = Ns Sy on Ns | Ns Sy off
886Controls whether the access time for files is updated when they are read.
887Turning this property off avoids producing write traffic when reading files and
888can result in significant performance gains, though it might confuse mailers
889and other similar utilities. The default value is
890.Sy on .
891.It Sy canmount Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy noauto
892If this property is set to
893.Sy off ,
894the file system cannot be mounted, and is ignored by
895.Nm zfs Cm mount Fl a .
896Setting this property to
897.Sy off
898is similar to setting the
899.Sy mountpoint
900property to
901.Sy none ,
902except that the dataset still has a normal
903.Sy mountpoint
904property, which can be inherited. Setting this property to
905.Sy off
906allows datasets to be used solely as a mechanism to inherit properties. One
907example of setting
908.Sy canmount Ns = Ns Sy off
909is to have two datasets with the same
910.Sy mountpoint ,
911so that the children of both datasets appear in the same directory, but might
912have different inherited characteristics.
913.Pp
914When set to
915.Sy noauto ,
916a dataset can only be mounted and unmounted explicitly. The dataset is not
917mounted automatically when the dataset is created or imported, nor is it mounted
918by the
919.Nm zfs Cm mount Fl a
920command or unmounted by the
921.Nm zfs Cm unmount Fl a
922command.
923.Pp
924This property is not inherited.
925.It Xo
926.Sy checksum Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy fletcher2 Ns | Ns
927.Sy fletcher4 Ns | Ns Sy sha256 Ns | Ns Sy noparity Ns | Ns
928.Sy sha512 Ns | Ns Sy skein Ns | Ns Sy edonr
929.Xc
930Controls the checksum used to verify data integrity. The default value is
931.Sy on ,
932which automatically selects an appropriate algorithm
933.Po currently,
934.Sy fletcher4 ,
935but this may change in future releases
936.Pc .
937The value
938.Sy off
939disables integrity checking on user data. The value
940.Sy noparity
941not only disables integrity but also disables maintaining parity for user data.
942This setting is used internally by a dump device residing on a RAID-Z pool and
943should not be used by any other dataset. Disabling checksums is
944.Sy NOT
945a recommended practice.
946.Pp
947The
948.Sy sha512 ,
949.Sy skein ,
950and
951.Sy edonr
952checksum algorithms require enabling the appropriate features on the
953pool. Please see
954.Xr zpool-features 5
955for more information on these algorithms.
956.Pp
957Changing this property affects only newly-written data.
958.It Xo
959.Sy compression Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Sy gzip Ns | Ns
960.Sy gzip- Ns Em N Ns | Ns Sy lz4 Ns | Ns Sy lzjb Ns | Ns Sy zle
961.Xc
962Controls the compression algorithm used for this dataset.
963.Pp
964Setting compression to
965.Sy on
966indicates that the current default compression algorithm should be used. The
967default balances compression and decompression speed, with compression ratio and
968is expected to work well on a wide variety of workloads.  Unlike all other
969settings for this property,
970.Sy on
971does not select a fixed compression type. As new compression algorithms are
972added to ZFS and enabled on a pool, the default compression algorithm may
973change. The current default compression algorthm is either
974.Sy lzjb
975or, if the
976.Sy lz4_compress
977feature is enabled,
978.Sy lz4 .
979.Pp
980The
981.Sy lz4
982compression algorithm is a high-performance replacement for the
983.Sy lzjb
984algorithm. It features significantly faster compression and decompression, as
985well as a moderately higher compression ratio than
986.Sy lzjb ,
987but can only be used on pools with the
988.Sy lz4_compress
989feature set to
990.Sy enabled .
991See
992.Xr zpool-features 5
993for details on ZFS feature flags and the
994.Sy lz4_compress
995feature.
996.Pp
997The
998.Sy lzjb
999compression algorithm is optimized for performance while providing decent data
1000compression.
1001.Pp
1002The
1003.Sy gzip
1004compression algorithm uses the same compression as the
1005.Xr gzip 1
1006command. You can specify the
1007.Sy gzip
1008level by using the value
1009.Sy gzip- Ns Em N ,
1010where
1011.Em N
1012is an integer from 1
1013.Pq fastest
1014to 9
1015.Pq best compression ratio .
1016Currently,
1017.Sy gzip
1018is equivalent to
1019.Sy gzip-6
1020.Po which is also the default for
1021.Xr gzip 1
1022.Pc .
1023.Pp
1024The
1025.Sy zle
1026compression algorithm compresses runs of zeros.
1027.Pp
1028This property can also be referred to by its shortened column name
1029\fBcompress\fR. Changing this property affects only newly-written data.
1030.It Sy copies Ns = Ns Sy 1 Ns | Ns Sy 2 Ns | Ns Sy 3
1031Controls the number of copies of data stored for this dataset. These copies are
1032in addition to any redundancy provided by the pool, for example, mirroring or
1033RAID-Z. The copies are stored on different disks, if possible. The space used
1034by multiple copies is charged to the associated file and dataset, changing the
1035.Sy used
1036property and counting against quotas and reservations.
1037.Pp
1038Changing this property only affects newly-written data. Therefore, set this
1039property at file system creation time by using the
1040.Fl o Sy copies Ns = Ns Ar N
1041option.
1042.It Sy devices Ns = Ns Sy on Ns | Ns Sy off
1043Controls whether device nodes can be opened on this file system. The default
1044value is
1045.Sy on .
1046.It Sy exec Ns = Ns Sy on Ns | Ns Sy off
1047Controls whether processes can be executed from within this file system. The
1048default value is
1049.Sy on .
1050.It Sy filesystem_limit Ns = Ns Em count Ns | Ns Sy none
1051Limits the number of filesystems and volumes that can exist under this point in
1052the dataset tree. The limit is not enforced if the user is allowed to change
1053the limit. Setting a
1054.Sy filesystem_limit
1055to
1056.Sy on
1057a descendent of a filesystem that already has a
1058.Sy filesystem_limit
1059does not override the ancestor's
1060.Sy filesystem_limit ,
1061but rather imposes an additional limit. This feature must be enabled to be used
1062.Po see
1063.Xr zpool-features 5
1064.Pc .
1065.It Sy mountpoint Ns = Ns Pa path Ns | Ns Sy none Ns | Ns Sy legacy
1066Controls the mount point used for this file system. See the
1067.Sx Mount Points
1068section for more information on how this property is used.
1069.Pp
1070When the
1071.Sy mountpoint
1072property is changed for a file system, the file system and any children that
1073inherit the mount point are unmounted. If the new value is
1074.Sy legacy ,
1075then they remain unmounted. Otherwise, they are automatically remounted in the
1076new location if the property was previously
1077.Sy legacy
1078or
1079.Sy none ,
1080or if they were mounted before the property was changed. In addition, any shared
1081file systems are unshared and shared in the new location.
1082.It Sy nbmand Ns = Ns Sy on Ns | Ns Sy off
1083Controls whether the file system should be mounted with
1084.Sy nbmand
1085.Pq Non Blocking mandatory locks .
1086This is used for SMB clients. Changes to this property only take effect when the
1087file system is umounted and remounted. See
1088.Xr mount 1M
1089for more information on
1090.Sy nbmand
1091mounts.
1092.It Sy primarycache Ns = Ns Sy all Ns | Ns Sy none Ns | Ns Sy metadata
1093Controls what is cached in the primary cache
1094.Pq ARC .
1095If this property is set to
1096.Sy all ,
1097then both user data and metadata is cached. If this property is set to
1098.Sy none ,
1099then neither user data nor metadata is cached. If this property is set to
1100.Sy metadata ,
1101then only metadata is cached. The default value is
1102.Sy all .
1103.It Sy quota Ns = Ns Em size Ns | Ns Sy none
1104Limits the amount of space a dataset and its descendents can consume. This
1105property enforces a hard limit on the amount of space used. This includes all
1106space consumed by descendents, including file systems and snapshots. Setting a
1107quota on a descendent of a dataset that already has a quota does not override
1108the ancestor's quota, but rather imposes an additional limit.
1109.Pp
1110Quotas cannot be set on volumes, as the
1111.Sy volsize
1112property acts as an implicit quota.
1113.It Sy snapshot_limit Ns = Ns Em count Ns | Ns Sy none
1114Limits the number of snapshots that can be created on a dataset and its
1115descendents. Setting a
1116.Sy snapshot_limit
1117on a descendent of a dataset that already has a
1118.Sy snapshot_limit
1119does not override the ancestor's
1120.Sy snapshot_limit ,
1121but rather imposes an additional limit. The limit is not enforced if the user is
1122allowed to change the limit. For example, this means that recursive snapshots
1123taken from the global zone are counted against each delegated dataset within
1124a zone. This feature must be enabled to be used
1125.Po see
1126.Xr zpool-features 5
1127.Pc .
1128.It Sy userquota@ Ns Em user Ns = Ns Em size Ns | Ns Sy none
1129Limits the amount of space consumed by the specified user. User space
1130consumption is identified by the
1131.Sy userspace@ Ns Em user
1132property.
1133.Pp
1134Enforcement of user quotas may be delayed by several seconds. This delay means
1135that a user might exceed their quota before the system notices that they are
1136over quota and begins to refuse additional writes with the
1137.Er EDQUOT
1138error message. See the
1139.Nm zfs Cm userspace
1140subcommand for more information.
1141.Pp
1142Unprivileged users can only access their own groups' space usage. The root
1143user, or a user who has been granted the
1144.Sy userquota
1145privilege with
1146.Nm zfs Cm allow ,
1147can get and set everyone's quota.
1148.Pp
1149This property is not available on volumes, on file systems before version 4, or
1150on pools before version 15. The
1151.Sy userquota@ Ns Em ...
1152properties are not displayed by
1153.Nm zfs Cm get Sy all .
1154The user's name must be appended after the
1155.Sy @
1156symbol, using one of the following forms:
1157.Bl -bullet
1158.It
1159.Em POSIX name
1160.Po for example,
1161.Sy joe
1162.Pc
1163.It
1164.Em POSIX numeric ID
1165.Po for example,
1166.Sy 789
1167.Pc
1168.It
1169.Em SID name
1170.Po for example,
1171.Sy joe.smith@mydomain
1172.Pc
1173.It
1174.Em SID numeric ID
1175.Po for example,
1176.Sy S-1-123-456-789
1177.Pc
1178.El
1179.It Sy groupquota@ Ns Em group Ns = Ns Em size Ns | Ns Sy none
1180Limits the amount of space consumed by the specified group. Group space
1181consumption is identified by the
1182.Sy groupused@ Ns Em group
1183property.
1184.Pp
1185Unprivileged users can access only their own groups' space usage. The root
1186user, or a user who has been granted the
1187.Sy groupquota
1188privilege with
1189.Nm zfs Cm allow ,
1190can get and set all groups' quotas.
1191.It Sy readonly Ns = Ns Sy on Ns | Ns Sy off
1192Controls whether this dataset can be modified. The default value is
1193.Sy off .
1194.Pp
1195This property can also be referred to by its shortened column name,
1196.Sy rdonly .
1197.It Sy recordsize Ns = Ns Em size
1198Specifies a suggested block size for files in the file system. This property is
1199designed solely for use with database workloads that access files in fixed-size
1200records. ZFS automatically tunes block sizes according to internal algorithms
1201optimized for typical access patterns.
1202.Pp
1203For databases that create very large files but access them in small random
1204chunks, these algorithms may be suboptimal. Specifying a
1205.Sy recordsize
1206greater than or equal to the record size of the database can result in
1207significant performance gains. Use of this property for general purpose file
1208systems is strongly discouraged, and may adversely affect performance.
1209.Pp
1210The size specified must be a power of two greater than or equal to 512 and less
1211than or equal to 128 Kbytes. If the
1212.Sy large_blocks
1213feature is enabled on the pool, the size may be up to 1 Mbyte. See
1214.Xr zpool-features 5
1215for details on ZFS feature flags.
1216.Pp
1217Changing the file system's
1218.Sy recordsize
1219affects only files created afterward; existing files are unaffected.
1220.Pp
1221This property can also be referred to by its shortened column name,
1222.Sy recsize .
1223.It Sy redundant_metadata Ns = Ns Sy all Ns | Ns Sy most
1224Controls what types of metadata are stored redundantly. ZFS stores an extra copy
1225of metadata, so that if a single block is corrupted, the amount of user data
1226lost is limited. This extra copy is in addition to any redundancy provided at
1227the pool level
1228.Pq e.g. by mirroring or RAID-Z ,
1229and is in addition to an extra copy specified by the
1230.Sy copies
1231property
1232.Pq up to a total of 3 copies .
1233For example if the pool is mirrored,
1234.Sy copies Ns = Ns 2 ,
1235and
1236.Sy redundant_metadata Ns = Ns Sy most ,
1237then ZFS stores 6 copies of most metadata, and 4 copies of data and some
1238metadata.
1239.Pp
1240When set to
1241.Sy all ,
1242ZFS stores an extra copy of all metadata. If a single on-disk block is corrupt,
1243at worst a single block of user data
1244.Po which is
1245.Sy recordsize
1246bytes long
1247.Pc
1248can be lost.
1249.Pp
1250When set to
1251.Sy most ,
1252ZFS stores an extra copy of most types of metadata. This can improve performance
1253of random writes, because less metadata must be written. In practice, at worst
1254about 100 blocks
1255.Po of
1256.Sy recordsize
1257bytes each
1258.Pc
1259of user data can be lost if a single on-disk block is corrupt. The exact
1260behavior of which metadata blocks are stored redundantly may change in future
1261releases.
1262.Pp
1263The default value is
1264.Sy all .
1265.It Sy refquota Ns = Ns Em size Ns | Ns Sy none
1266Limits the amount of space a dataset can consume. This property enforces a hard
1267limit on the amount of space used. This hard limit does not include space used
1268by descendents, including file systems and snapshots.
1269.It Sy refreservation Ns = Ns Em size Ns | Ns Sy none
1270The minimum amount of space guaranteed to a dataset, not including its
1271descendents. When the amount of space used is below this value, the dataset is
1272treated as if it were taking up the amount of space specified by
1273.Sy refreservation .
1274The
1275.Sy refreservation
1276reservation is accounted for in the parent datasets' space used, and counts
1277against the parent datasets' quotas and reservations.
1278.Pp
1279If
1280.Sy refreservation
1281is set, a snapshot is only allowed if there is enough free pool space outside of
1282this reservation to accommodate the current number of
1283.Qq referenced
1284bytes in the dataset.
1285.Pp
1286This property can also be referred to by its shortened column name,
1287.Sy refreserv .
1288.It Sy reservation Ns = Ns Em size Ns | Ns Sy none
1289The minimum amount of space guaranteed to a dataset and its descendents. When
1290the amount of space used is below this value, the dataset is treated as if it
1291were taking up the amount of space specified by its reservation. Reservations
1292are accounted for in the parent datasets' space used, and count against the
1293parent datasets' quotas and reservations.
1294.Pp
1295This property can also be referred to by its shortened column name,
1296.Sy reserv .
1297.It Sy secondarycache Ns = Ns Sy all Ns | Ns Sy none Ns | Ns Sy metadata
1298Controls what is cached in the secondary cache
1299.Pq L2ARC .
1300If this property is set to
1301.Sy all ,
1302then both user data and metadata is cached. If this property is set to
1303.Sy none ,
1304then neither user data nor metadata is cached. If this property is set to
1305.Sy metadata ,
1306then only metadata is cached. The default value is
1307.Sy all .
1308.It Sy setuid Ns = Ns Sy on Ns | Ns Sy off
1309Controls whether the setuid bit is respected for the file system. The default
1310value is
1311.Sy on .
1312.It Sy sharesmb Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Em opts
1313Controls whether the file system is shared via SMB, and what options are to be
1314used. A file system with the
1315.Sy sharesmb
1316property set to
1317.Sy off
1318is managed through traditional tools such as
1319.Xr sharemgr 1M .
1320Otherwise, the file system is automatically shared and unshared with the
1321.Nm zfs Cm share
1322and
1323.Nm zfs Cm unshare
1324commands. If the property is set to
1325.Sy on ,
1326the
1327.Xr sharemgr 1M
1328command is invoked with no options. Otherwise, the
1329.Xr sharemgr 1M
1330command is invoked with options equivalent to the contents of this property.
1331.Pp
1332Because SMB shares requires a resource name, a unique resource name is
1333constructed from the dataset name. The constructed name is a copy of the dataset
1334name except that the characters in the dataset name, which would be illegal in
1335the resource name, are replaced with underscore
1336.Pq Sy _
1337characters. A pseudo property
1338.Qq name
1339is also supported that allows you to replace the data set name with a specified
1340name. The specified name is then used to replace the prefix dataset in the case
1341of inheritance. For example, if the dataset
1342.Em data/home/john
1343is set to
1344.Sy name Ns = Ns Sy john ,
1345then
1346.Em data/home/john
1347has a resource name of
1348.Sy john .
1349If a child dataset
1350.Em data/home/john/backups
1351is shared, it has a resource name of
1352.Sy john_backups .
1353.Pp
1354When SMB shares are created, the SMB share name appears as an entry in the
1355.Pa .zfs/shares
1356directory. You can use the
1357.Nm ls
1358or
1359.Nm chmod
1360command to display the share-level ACLs on the entries in this directory.
1361.Pp
1362When the
1363.Sy sharesmb
1364property is changed for a dataset, the dataset and any children inheriting the
1365property are re-shared with the new options, only if the property was previously
1366set to
1367.Sy off ,
1368or if they were shared before the property was changed. If the new property is
1369set to
1370.Sy off ,
1371the file systems are unshared.
1372.It Sy sharenfs Ns = Ns Sy on Ns | Ns Sy off Ns | Ns Em opts
1373Controls whether the file system is shared via NFS, and what options are to be
1374used. A file system with a
1375.Sy sharenfs
1376property of
1377.Sy off
1378is managed through traditional tools such as
1379.Xr share 1M ,
1380.Xr unshare 1M ,
1381and
1382.Xr dfstab 4 .
1383Otherwise, the file system is automatically shared and unshared with the
1384.Nm zfs Cm share
1385and
1386.Nm zfs Cm unshare
1387commands. If the property is set to
1388.Sy on ,
1389.Xr share 1M
1390command is invoked with no options. Otherwise, the
1391.Xr share 1M
1392command is invoked with options equivalent to the contents of this property.
1393.Pp
1394When the
1395.Sy sharenfs
1396property is changed for a dataset, the dataset and any children inheriting the
1397property are re-shared with the new options, only if the property was previously
1398.Sy off ,
1399or if they were shared before the property was changed. If the new property is
1400.Sy off ,
1401the file systems are unshared.
1402.It Sy logbias Ns = Ns Sy latency Ns | Ns Sy throughput
1403Provide a hint to ZFS about handling of synchronous requests in this dataset. If
1404.Sy logbias
1405is set to
1406.Sy latency
1407.Pq the default ,
1408ZFS will use pool log devices
1409.Pq if configured
1410to handle the requests at low latency. If
1411.Sy logbias
1412is set to
1413.Sy throughput ,
1414ZFS will not use configured pool log devices. ZFS will instead optimize
1415synchronous operations for global pool throughput and efficient use of
1416resources.
1417.It Sy snapdir Ns = Ns Sy hidden Ns | Ns Sy visible
1418Controls whether the
1419.Pa .zfs
1420directory is hidden or visible in the root of the file system as discussed in
1421the
1422.Sx Snapshots
1423section. The default value is
1424.Sy hidden .
1425.It Sy sync Ns = Ns Sy standard Ns | Ns Sy always Ns | Ns Sy disabled
1426Controls the behavior of synchronous requests
1427.Pq e.g. fsync, O_DSYNC .
1428.Sy standard
1429is the
1430.Tn POSIX
1431specified behavior of ensuring all synchronous requests are written to stable
1432storage and all devices are flushed to ensure data is not cached by device
1433controllers
1434.Pq this is the default .
1435.Sy always
1436causes every file system transaction to be written and flushed before its
1437system call returns. This has a large performance penalty.
1438.Sy disabled
1439disables synchronous requests. File system transactions are only committed to
1440stable storage periodically. This option will give the highest performance.
1441However, it is very dangerous as ZFS would be ignoring the synchronous
1442transaction demands of applications such as databases or NFS. Administrators
1443should only use this option when the risks are understood.
1444.It Sy version Ns = Ns Em N Ns | Ns Sy current
1445The on-disk version of this file system, which is independent of the pool
1446version. This property can only be set to later supported versions. See the
1447.Nm zfs Cm upgrade
1448command.
1449.It Sy volsize Ns = Ns Em size
1450For volumes, specifies the logical size of the volume. By default, creating a
1451volume establishes a reservation of equal size. For storage pools with a version
1452number of 9 or higher, a
1453.Sy refreservation
1454is set instead. Any changes to
1455.Sy volsize
1456are reflected in an equivalent change to the reservation
1457.Po or
1458.Sy refreservation
1459.Pc .
1460The
1461.Sy volsize
1462can only be set to a multiple of
1463.Sy volblocksize ,
1464and cannot be zero.
1465.Pp
1466The reservation is kept equal to the volume's logical size to prevent unexpected
1467behavior for consumers. Without the reservation, the volume could run out of
1468space, resulting in undefined behavior or data corruption, depending on how the
1469volume is used. These effects can also occur when the volume size is changed
1470while it is in use
1471.Pq particularly when shrinking the size .
1472Extreme care should be used when adjusting the volume size.
1473.Pp
1474Though not recommended, a
1475.Qq sparse volume
1476.Po also known as
1477.Qq thin provisioning
1478.Pc
1479can be created by specifying the
1480.Fl s
1481option to the
1482.Nm zfs Cm create Fl V
1483command, or by changing the reservation after the volume has been created. A
1484.Qq sparse volume
1485is a volume where the reservation is less then the volume size. Consequently,
1486writes to a sparse volume can fail with
1487.Er ENOSPC
1488when the pool is low on space. For a sparse volume, changes to
1489.Sy volsize
1490are not reflected in the reservation.
1491.It Sy vscan Ns = Ns Sy on Ns | Ns Sy off
1492Controls whether regular files should be scanned for viruses when a file is
1493opened and closed. In addition to enabling this property, the virus scan
1494service must also be enabled for virus scanning to occur. The default value is
1495.Sy off .
1496.It Sy xattr Ns = Ns Sy on Ns | Ns Sy off
1497Controls whether extended attributes are enabled for this file system. The
1498default value is
1499.Sy on .
1500.It Sy zoned Ns = Ns Sy on Ns | Ns Sy off
1501Controls whether the dataset is managed from a non-global zone. See the
1502.Sx Zones
1503section for more information. The default value is
1504.Sy off .
1505.El
1506.Pp
1507The following three properties cannot be changed after the file system is
1508created, and therefore, should be set when the file system is created. If the
1509properties are not set with the
1510.Nm zfs Cm create
1511or
1512.Nm zpool Cm create
1513commands, these properties are inherited from the parent dataset. If the parent
1514dataset lacks these properties due to having been created prior to these
1515features being supported, the new file system will have the default values for
1516these properties.
1517.Bl -tag -width ""
1518.It Xo
1519.Sy casesensitivity Ns = Ns Sy sensitive Ns | Ns
1520.Sy insensitive Ns | Ns Sy mixed
1521.Xc
1522Indicates whether the file name matching algorithm used by the file system
1523should be case-sensitive, case-insensitive, or allow a combination of both
1524styles of matching. The default value for the
1525.Sy casesensitivity
1526property is
1527.Sy sensitive .
1528Traditionally,
1529.Ux
1530and
1531.Tn POSIX
1532file systems have case-sensitive file names.
1533.Pp
1534The
1535.Sy mixed
1536value for the
1537.Sy casesensitivity
1538property indicates that the file system can support requests for both
1539case-sensitive and case-insensitive matching behavior. Currently,
1540case-insensitive matching behavior on a file system that supports mixed behavior
1541is limited to the SMB server product. For more information about the
1542.Sy mixed
1543value behavior, see the "ZFS Administration Guide".
1544.It Xo
1545.Sy normalization Ns = Ns Sy none Ns | Ns Sy formC Ns | Ns
1546.Sy formD Ns | Ns Sy formKC Ns | Ns Sy formKD
1547.Xc
1548Indicates whether the file system should perform a
1549.Sy unicode
1550normalization of file names whenever two file names are compared, and which
1551normalization algorithm should be used. File names are always stored unmodified,
1552names are normalized as part of any comparison process. If this property is set
1553to a legal value other than
1554.Sy none ,
1555and the
1556.Sy utf8only
1557property was left unspecified, the
1558.Sy utf8only
1559property is automatically set to
1560.Sy on .
1561The default value of the
1562.Sy normalization
1563property is
1564.Sy none .
1565This property cannot be changed after the file system is created.
1566.It Sy utf8only Ns = Ns Sy on Ns | Ns Sy off
1567Indicates whether the file system should reject file names that include
1568characters that are not present in the
1569.Sy UTF-8
1570character code set. If this property is explicitly set to
1571.Sy off ,
1572the normalization property must either not be explicitly set or be set to
1573.Sy none .
1574The default value for the
1575.Sy utf8only
1576property is
1577.Sy off .
1578This property cannot be changed after the file system is created.
1579.El
1580.Pp
1581The
1582.Sy casesensitivity ,
1583.Sy normalization ,
1584and
1585.Sy utf8only
1586properties are also new permissions that can be assigned to non-privileged users
1587by using the ZFS delegated administration feature.
1588.Ss "Temporary Mount Point Properties"
1589When a file system is mounted, either through
1590.Xr mount 1M
1591for legacy mounts or the
1592.Nm zfs Cm mount
1593command for normal file systems, its mount options are set according to its
1594properties. The correlation between properties and mount options is as follows:
1595.Bd -literal
1596    PROPERTY                MOUNT OPTION
1597    devices                 devices/nodevices
1598    exec                    exec/noexec
1599    readonly                ro/rw
1600    setuid                  setuid/nosetuid
1601    xattr                   xattr/noxattr
1602.Ed
1603.Pp
1604In addition, these options can be set on a per-mount basis using the
1605.Fl o
1606option, without affecting the property that is stored on disk. The values
1607specified on the command line override the values stored in the dataset. The
1608.Sy nosuid
1609option is an alias for
1610.Sy nodevices Ns , Ns Sy nosetuid .
1611These properties are reported as
1612.Qq temporary
1613by the
1614.Nm zfs Cm get
1615command. If the properties are changed while the dataset is mounted, the new
1616setting overrides any temporary settings.
1617.Ss "User Properties"
1618In addition to the standard native properties, ZFS supports arbitrary user
1619properties. User properties have no effect on ZFS behavior, but applications or
1620administrators can use them to annotate datasets
1621.Pq file systems, volumes, and snapshots .
1622.Pp
1623User property names must contain a colon
1624.Pq Qq Sy \&:
1625character to distinguish them from native properties. They may contain lowercase
1626letters, numbers, and the following punctuation characters: colon
1627.Pq Qq Sy \&: ,
1628dash
1629.Pq Qq Sy - ,
1630period
1631.Pq Qq Sy \&. ,
1632and underscore
1633.Pq Qq Sy _ .
1634The expected convention is that the property name is divided into two portions
1635such as
1636.Em module Ns : Ns Em property ,
1637but this namespace is not enforced by ZFS.
1638User property names can be at most 256 characters, and cannot begin with a dash
1639.Pq Qq Sy - .
1640.Pp
1641When making programmatic use of user properties, it is strongly suggested to use
1642a reversed
1643.Sy DNS
1644domain name for the
1645.Em module
1646component of property names to reduce the chance that two
1647independently-developed packages use the same property name for different
1648purposes.
1649.Pp
1650The values of user properties are arbitrary strings, are always inherited, and
1651are never validated. All of the commands that operate on properties
1652.Po Nm zfs Cm list ,
1653.Nm zfs Cm get ,
1654.Nm zfs Cm set ,
1655and so forth
1656.Pc
1657can be used to manipulate both native properties and user properties. Use the
1658.Nm zfs Cm inherit
1659command to clear a user property . If the property is not defined in any parent
1660dataset, it is removed entirely. Property values are limited to 1024
1661characters.
1662.Ss ZFS Volumes as Swap or Dump Devices
1663During an initial installation a swap device and dump device are created on ZFS
1664volumes in the ZFS root pool. By default, the swap area size is based on 1/2 the
1665size of physical memory up to 2 Gbytes. The size of the dump device depends on
1666the kernel's requirements at installation time. Separate ZFS volumes must be
1667used for the swap area and dump devices. Do not swap to a file on a ZFS file
1668system. A ZFS swap file configuration is not supported.
1669.Pp
1670If you need to change your swap area or dump device after the system is
1671installed or upgraded, use the
1672.Xr swap 1M
1673and
1674.Xr dumpadm 1M
1675commands.
1676.Sh SUBCOMMANDS
1677All subcommands that modify state are logged persistently to the pool in their
1678original form.
1679.Bl -tag -width ""
1680.It Nm Fl \?
1681Displays a help message.
1682.It Xo
1683.Nm
1684.Cm create
1685.Op Fl p
1686.Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
1687.Ar filesystem
1688.Xc
1689Creates a new ZFS file system. The file system is automatically mounted
1690according to the
1691.Sy mountpoint
1692property inherited from the parent.
1693.Bl -tag -width "-o"
1694.It Fl o Ar property Ns = Ns Ar value
1695Sets the specified property as if the command
1696.Nm zfs Cm set Ar property Ns = Ns Ar value
1697was invoked at the same time the dataset was created. Any editable ZFS property
1698can also be set at creation time. Multiple
1699.Fl o
1700options can be specified. An error results if the same property is specified in
1701multiple
1702.Fl o
1703options.
1704.It Fl p
1705Creates all the non-existing parent datasets. Datasets created in this manner
1706are automatically mounted according to the
1707.Sy mountpoint
1708property inherited from their parent. Any property specified on the command line
1709using the
1710.Fl o
1711option is ignored. If the target filesystem already exists, the operation
1712completes successfully.
1713.El
1714.It Xo
1715.Nm
1716.Cm create
1717.Op Fl ps
1718.Op Fl b Ar blocksize
1719.Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
1720.Fl V Ar size Ar volume
1721.Xc
1722Creates a volume of the given size. The volume is exported as a block device in
1723.Pa /dev/zvol/{dsk,rdsk}/path ,
1724where
1725.Em path
1726is the name of the volume in the ZFS namespace. The size represents the logical
1727size as exported by the device. By default, a reservation of equal size is
1728created.
1729.Pp
1730.Ar size
1731is automatically rounded up to the nearest 128 Kbytes to ensure that the volume
1732has an integral number of blocks regardless of
1733.Sy blocksize .
1734.Bl -tag -width "-b"
1735.It Fl b Ar blocksize
1736Equivalent to
1737.Fl o Sy volblocksize Ns = Ns Ar blocksize .
1738If this option is specified in conjunction with
1739.Fl o Sy volblocksize ,
1740the resulting behavior is undefined.
1741.It Fl o Ar property Ns = Ns Ar value
1742Sets the specified property as if the
1743.Nm zfs Cm set Ar property Ns = Ns Ar value
1744command was invoked at the same time the dataset was created. Any editable ZFS
1745property can also be set at creation time. Multiple
1746.Fl o
1747options can be specified. An error results if the same property is specified in
1748multiple
1749.Fl o
1750options.
1751.It Fl p
1752Creates all the non-existing parent datasets. Datasets created in this manner
1753are automatically mounted according to the
1754.Sy mountpoint
1755property inherited from their parent. Any property specified on the command line
1756using the
1757.Fl o
1758option is ignored. If the target filesystem already exists, the operation
1759completes successfully.
1760.It Fl s
1761Creates a sparse volume with no reservation. See
1762.Sy volsize
1763in the
1764.Sx Native Properties
1765section for more information about sparse volumes.
1766.El
1767.It Xo
1768.Nm
1769.Cm destroy
1770.Op Fl Rfnprv
1771.Ar filesystem Ns | Ns Ar volume
1772.Xc
1773Destroys the given dataset. By default, the command unshares any file systems
1774that are currently shared, unmounts any file systems that are currently
1775mounted, and refuses to destroy a dataset that has active dependents
1776.Pq children or clones .
1777.Bl -tag -width "-R"
1778.It Fl R
1779Recursively destroy all dependents, including cloned file systems outside the
1780target hierarchy.
1781.It Fl f
1782Force an unmount of any file systems using the
1783.Nm unmount Fl f
1784command. This option has no effect on non-file systems or unmounted file
1785systems.
1786.It Fl n
1787Do a dry-run
1788.Pq Qq No-op
1789deletion. No data will be deleted. This is useful in conjunction with the
1790.Fl v
1791or
1792.Fl p
1793flags to determine what data would be deleted.
1794.It Fl p
1795Print machine-parsable verbose information about the deleted data.
1796.It Fl r
1797Recursively destroy all children.
1798.It Fl v
1799Print verbose information about the deleted data.
1800.El
1801.Pp
1802Extreme care should be taken when applying either the
1803.Fl r
1804or the
1805.Fl R
1806options, as they can destroy large portions of a pool and cause unexpected
1807behavior for mounted file systems in use.
1808.It Xo
1809.Nm
1810.Cm destroy
1811.Op Fl Rdnprv
1812.Ar filesystem Ns | Ns Ar volume Ns @ Ns Ar snap Ns
1813.Oo % Ns Ar snap Ns Oo , Ns Ar snap Ns Oo % Ns Ar snap Oc Oc Oc Ns ...
1814.Xc
1815The given snapshots are destroyed immediately if and only if the
1816.Nm zfs Cm destroy
1817command without the
1818.Fl d
1819option would have destroyed it. Such immediate destruction would occur, for
1820example, if the snapshot had no clones and the user-initiated reference count
1821were zero.
1822.Pp
1823If a snapshot does not qualify for immediate destruction, it is marked for
1824deferred deletion. In this state, it exists as a usable, visible snapshot until
1825both of the preconditions listed above are met, at which point it is destroyed.
1826.Pp
1827An inclusive range of snapshots may be specified by separating the first and
1828last snapshots with a percent sign. The first and/or last snapshots may be left
1829blank, in which case the filesystem's oldest or newest snapshot will be implied.
1830.Pp
1831Multiple snapshots
1832.Pq or ranges of snapshots
1833of the same filesystem or volume may be specified in a comma-separated list of
1834snapshots. Only the snapshot's short name
1835.Po the part after the
1836.Sy @
1837.Pc
1838should be specified when using a range or comma-separated list to identify
1839multiple snapshots.
1840.Bl -tag -width "-R"
1841.It Fl R
1842Recursively destroy all clones of these snapshots, including the clones,
1843snapshots, and children. If this flag is specified, the
1844.Fl d
1845flag will have no effect.
1846.It Fl d
1847Defer snapshot deletion.
1848.It Fl n
1849Do a dry-run
1850.Pq Qq No-op
1851deletion. No data will be deleted. This is
1852useful in conjunction with the
1853.Fl p
1854or
1855.Fl v
1856flags to determine what data would be deleted.
1857.It Fl p
1858Print machine-parsable verbose information about the deleted data.
1859.It Fl r
1860Destroy
1861.Pq or mark for deferred deletion
1862all snapshots with this name in descendent file systems.
1863.It Fl v
1864Print verbose information about the deleted data.
1865.Pp
1866Extreme care should be taken when applying either the
1867.Fl r
1868or the
1869.Fl R
1870options, as they can destroy large portions of a pool and cause unexpected
1871behavior for mounted file systems in use.
1872.El
1873.It Xo
1874.Nm
1875.Cm destroy
1876.Ar filesystem Ns | Ns Ar volume Ns # Ns Ar bookmark
1877.Xc
1878The given bookmark is destroyed.
1879.It Xo
1880.Nm
1881.Cm snapshot
1882.Op Fl r
1883.Oo Fl o Ar property Ns = Ns value Oc Ns ...
1884.Ar filesystem Ns @ Ns Ar snapname Ns | Ns Ar volume Ns @ Ns Ar snapname Ns ...
1885.Xc
1886Creates snapshots with the given names. All previous modifications by successful
1887system calls to the file system are part of the snapshots. Snapshots are taken
1888atomically, so that all snapshots correspond to the same moment in time. See the
1889.Sx Snapshots
1890section for details.
1891.Bl -tag -width "-o"
1892.It Fl o Ar property Ns = Ns Ar value
1893Sets the specified property; see
1894.Nm zfs Cm create
1895for details.
1896.It Fl r
1897Recursively create snapshots of all descendent datasets
1898.El
1899.It Xo
1900.Nm
1901.Cm rollback
1902.Op Fl Rfr
1903.Ar snapshot
1904.Xc
1905Roll back the given dataset to a previous snapshot. When a dataset is rolled
1906back, all data that has changed since the snapshot is discarded, and the dataset
1907reverts to the state at the time of the snapshot. By default, the command
1908refuses to roll back to a snapshot other than the most recent one. In order to
1909do so, all intermediate snapshots and bookmarks must be destroyed by specifying
1910the
1911.Fl r
1912option.
1913.Pp
1914The
1915.Fl rR
1916options do not recursively destroy the child snapshots of a recursive snapshot.
1917Only direct snapshots of the specified filesystem are destroyed by either of
1918these options. To completely roll back a recursive snapshot, you must rollback
1919the individual child snapshots.
1920.Bl -tag -width "-R"
1921.It Fl R
1922Destroy any more recent snapshots and bookmarks, as well as any clones of those
1923snapshots.
1924.It Fl f
1925Used with the
1926.Fl R
1927option to force an unmount of any clone file systems that are to be destroyed.
1928.It Fl r
1929Destroy any snapshots and bookmarks more recent than the one specified.
1930.El
1931.It Xo
1932.Nm
1933.Cm clone
1934.Op Fl p
1935.Oo Fl o Ar property Ns = Ns Ar value Oc Ns ...
1936.Ar snapshot Ar filesystem Ns | Ns Ar volume
1937.Xc
1938Creates a clone of the given snapshot. See the
1939.Sx Clones
1940section for details. The target dataset can be located anywhere in the ZFS
1941hierarchy, and is created as the same type as the original.
1942.Bl -tag -width "-o"
1943.It Fl o Ar property Ns = Ns Ar value
1944Sets the specified property; see
1945.Nm zfs Cm create
1946for details.
1947.It Fl p
1948Creates all the non-existing parent datasets. Datasets created in this manner
1949are automatically mounted according to the
1950.Sy mountpoint
1951property inherited from their parent. If the target filesystem or volume already
1952exists, the operation completes successfully.
1953.El
1954.It Xo
1955.Nm
1956.Cm promote
1957.Ar clone-filesystem
1958.Xc
1959Promotes a clone file system to no longer be dependent on its
1960.Qq origin
1961snapshot. This makes it possible to destroy the file system that the clone was
1962created from. The clone parent-child dependency relationship is reversed, so
1963that the origin file system becomes a clone of the specified file system.
1964.Pp
1965The snapshot that was cloned, and any snapshots previous to this snapshot, are
1966now owned by the promoted clone. The space they use moves from the origin file
1967system to the promoted clone, so enough space must be available to accommodate
1968these snapshots. No new space is consumed by this operation, but the space
1969accounting is adjusted. The promoted clone must not have any conflicting
1970snapshot names of its own. The
1971.Cm rename
1972subcommand can be used to rename any conflicting snapshots.
1973.It Xo
1974.Nm
1975.Cm rename
1976.Op Fl f
1977.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
1978.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
1979.br
1980.Nm
1981.Cm rename
1982.Op Fl fp
1983.Ar filesystem Ns | Ns Ar volume
1984.Ar filesystem Ns | Ns Ar volume
1985.Xc
1986Renames the given dataset. The new target can be located anywhere in the ZFS
1987hierarchy, with the exception of snapshots. Snapshots can only be renamed within
1988the parent file system or volume. When renaming a snapshot, the parent file
1989system of the snapshot does not need to be specified as part of the second
1990argument. Renamed file systems can inherit new mount points, in which case they
1991are unmounted and remounted at the new mount point.
1992.Bl -tag -width "-a"
1993.It Fl f
1994Force unmount any filesystems that need to be unmounted in the process.
1995.It Fl p
1996Creates all the nonexistent parent datasets. Datasets created in this manner are
1997automatically mounted according to the
1998.Sy mountpoint
1999property inherited from their parent.
2000.El
2001.It Xo
2002.Nm
2003.Cm rename
2004.Fl r
2005.Ar snapshot Ar snapshot
2006.Xc
2007Recursively rename the snapshots of all descendent datasets. Snapshots are the
2008only dataset that can be renamed recursively.
2009.It Xo
2010.Nm
2011.Cm list
2012.Op Fl r Ns | Ns Fl d Ar depth
2013.Op Fl Hp
2014.Oo Fl o Ar property Ns Oo , Ns Ar property Oc Ns ... Oc
2015.Oo Fl s Ar property Oc Ns ...
2016.Oo Fl S Ar property Oc Ns ...
2017.Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2018.Oo Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Oc Ns ...
2019.Xc
2020Lists the property information for the given datasets in tabular form. If
2021specified, you can list property information by the absolute pathname or the
2022relative pathname. By default, all file systems and volumes are displayed.
2023Snapshots are displayed if the
2024.Sy listsnaps
2025property is
2026.Sy on
2027.Po the default is
2028.Sy off
2029.Pc .
2030The following fields are displayed,
2031.Sy name Ns , Ns Sy used Ns , Ns Sy available Ns , Ns Sy referenced Ns , Ns
2032.Sy mountpoint .
2033.Bl -tag -width "-H"
2034.It Fl H
2035Used for scripting mode. Do not print headers and separate fields by a single
2036tab instead of arbitrary white space.
2037.It Fl S Ar property
2038Same as the
2039.Fl s
2040option, but sorts by property in descending order.
2041.It Fl d Ar depth
2042Recursively display any children of the dataset, limiting the recursion to
2043.It Fl o Ar property
2044A comma-separated list of properties to display. The property must be:
2045.Bl -bullet
2046.It
2047One of the properties described in the
2048.Sx Native Properties
2049section
2050.It
2051A user property
2052.It
2053The value
2054.Sy name
2055to display the dataset name
2056.It
2057The value
2058.Sy space
2059to display space usage properties on file systems and volumes. This is a
2060shortcut for specifying
2061.Fl o Sy name Ns , Ns Sy avail Ns , Ns Sy used Ns , Ns Sy usedsnap Ns , Ns
2062.Sy usedds Ns , Ns Sy usedrefreserv Ns , Ns Sy usedchild Fl t
2063.Sy filesystem Ns , Ns Sy volume
2064syntax.
2065.El
2066.It Fl p
2067Display numbers in parsable
2068.Pq exact
2069values.
2070.It Fl r
2071Recursively display any children of the dataset on the command line.
2072.Ar depth .
2073A depth of
2074.Sy 1
2075will display only the dataset and its direct children.
2076.It Fl s Ar property
2077A property for sorting the output by column in ascending order based on the
2078value of the property. The property must be one of the properties described in
2079the
2080.Sx Properties
2081section, or the special value
2082.Sy name
2083to sort by the dataset name. Multiple properties can be specified at one time
2084using multiple
2085.Fl s
2086property options. Multiple
2087.Fl s
2088options are evaluated from left to right in decreasing order of importance. The
2089following is a list of sorting criteria:
2090.Bl -bullet
2091.It
2092Numeric types sort in numeric order.
2093.It
2094String types sort in alphabetical order.
2095.It
2096Types inappropriate for a row sort that row to the literal bottom, regardless of
2097the specified ordering.
2098.El
2099.Pp
2100If no sorting options are specified the existing behavior of
2101.Nm zfs Cm list
2102is preserved.
2103.It Fl t Ar type
2104A comma-separated list of types to display, where
2105.Ar type
2106is one of
2107.Sy filesystem ,
2108.Sy snapshot ,
2109.Sy volume ,
2110.Sy bookmark ,
2111or
2112.Sy all .
2113For example, specifying
2114.Fl t Sy snapshot
2115displays only snapshots.
2116.El
2117.It Xo
2118.Nm
2119.Cm set
2120.Ar property Ns = Ns Ar value Oo Ar property Ns = Ns Ar value Oc Ns ...
2121.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
2122.Xc
2123Sets the property or list of properties to the given value(s) for each dataset.
2124Only some properties can be edited. See the
2125.Sx Properties
2126section for more information on what properties can be set and acceptable
2127values. Numeric values can be specified as exact values, or in a human-readable
2128form with a suffix of
2129.Sy B , K , M , G , T , P , E , Z
2130.Po for bytes, kilobytes, megabytes, gigabytes, terabytes, petabytes, exabytes,
2131or zettabytes, respectively
2132.Pc .
2133User properties can be set on snapshots. For more information, see the
2134.Sx User Properties
2135section.
2136.It Xo
2137.Nm
2138.Cm get
2139.Op Fl r Ns | Ns Fl d Ar depth
2140.Op Fl Hp
2141.Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
2142.Oo Fl s Ar source Ns Oo , Ns Ar source Oc Ns ... Oc
2143.Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2144.Cm all | Ar property Ns Oo , Ns Ar property Oc Ns ...
2145.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns | Ns Ar bookmark Ns ...
2146.Xc
2147Displays properties for the given datasets. If no datasets are specified, then
2148the command displays properties for all datasets on the system. For each
2149property, the following columns are displayed:
2150.Bd -literal
2151    name      Dataset name
2152    property  Property name
2153    value     Property value
2154    source    Property source. Can either be local, default,
2155              temporary, inherited, or none (-).
2156.Ed
2157.Pp
2158All columns are displayed by default, though this can be controlled by using the
2159.Fl o
2160option. This command takes a comma-separated list of properties as described in
2161the
2162.Sx Native Properties
2163and
2164.Sx User Properties
2165sections.
2166.Pp
2167The special value
2168.Sy all
2169can be used to display all properties that apply to the given dataset's type
2170.Pq filesystem, volume, snapshot, or bookmark .
2171.Bl -tag -width "-H"
2172.It Fl H
2173Display output in a form more easily parsed by scripts. Any headers are omitted,
2174and fields are explicitly separated by a single tab instead of an arbitrary
2175amount of space.
2176.It Fl d Ar depth
2177Recursively display any children of the dataset, limiting the recursion to
2178.Ar depth .
2179A depth of
2180.Sy 1
2181will display only the dataset and its direct children.
2182.It Fl o Ar field
2183A comma-separated list of columns to display.
2184.Sy name Ns , Ns Sy property Ns , Ns Sy value Ns , Ns Sy source
2185is the default value.
2186.It Fl p
2187Display numbers in parsable
2188.Pq exact
2189values.
2190.It Fl r
2191Recursively display properties for any children.
2192.It Fl s Ar source
2193A comma-separated list of sources to display. Those properties coming from a
2194source other than those in this list are ignored. Each source must be one of the
2195following:
2196.Sy local ,
2197.Sy default ,
2198.Sy inherited ,
2199.Sy temporary ,
2200and
2201.Sy none .
2202The default value is all sources.
2203.It Fl t Ar type
2204A comma-separated list of types to display, where
2205.Ar type
2206is one of
2207.Sy filesystem ,
2208.Sy snapshot ,
2209.Sy volume ,
2210.Sy bookmark ,
2211or
2212.Sy all .
2213.El
2214.It Xo
2215.Nm
2216.Cm inherit
2217.Op Fl rS
2218.Ar property Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot Ns ...
2219.Xc
2220Clears the specified property, causing it to be inherited from an ancestor,
2221restored to default if no ancestor has the property set, or with the
2222.Fl S
2223option reverted to the received value if one exists. See the
2224.Sx Properties
2225section for a listing of default values, and details on which properties can be
2226inherited.
2227.Bl -tag -width "-r"
2228.It Fl r
2229Recursively inherit the given property for all children.
2230.It Fl S
2231Revert the property to the received value if one exists; otherwise operate as
2232if the
2233.Fl S
2234option was not specified.
2235.El
2236.It Xo
2237.Nm
2238.Cm upgrade
2239.Xc
2240Displays a list of file systems that are not the most recent version.
2241.It Xo
2242.Nm
2243.Cm upgrade
2244.Fl v
2245.Xc
2246Displays a list of currently supported file system versions.
2247.It Xo
2248.Nm
2249.Cm upgrade
2250.Op Fl r
2251.Op Fl V Ar version
2252.Fl a | Ar filesystem
2253.Xc
2254Upgrades file systems to a new on-disk version. Once this is done, the file
2255systems will no longer be accessible on systems running older versions of the
2256software.
2257.Nm zfs Cm send
2258streams generated from new snapshots of these file systems cannot be accessed on
2259systems running older versions of the software.
2260.Pp
2261In general, the file system version is independent of the pool version. See
2262.Xr zpool 1M
2263for information on the
2264.Nm zpool Cm upgrade
2265command.
2266.Pp
2267In some cases, the file system version and the pool version are interrelated and
2268the pool version must be upgraded before the file system version can be upgraded.
2269.Bl -tag -width "-V"
2270.It Fl V Ar version
2271Upgrade to the specified
2272.Ar version .
2273If the
2274.Fl V
2275flag is not specified, this command upgrades to the most recent version. This
2276option can only be used to increase the version number, and only up to the most
2277recent version supported by this software.
2278.It Fl a
2279Upgrade all file systems on all imported pools.
2280.It Ar filesystem
2281Upgrade the specified file system.
2282.It Fl r
2283Upgrade the specified file system and all descendent file systems.
2284.El
2285.It Xo
2286.Nm
2287.Cm userspace
2288.Op Fl Hinp
2289.Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
2290.Oo Fl s Ar field Oc Ns ...
2291.Oo Fl S Ar field Oc Ns ...
2292.Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2293.Ar filesystem Ns | Ns Ar snapshot
2294.Xc
2295Displays space consumed by, and quotas on, each user in the specified filesystem
2296or snapshot. This corresponds to the
2297.Sy userused@ Ns Em user
2298and
2299.Sy userquota@ Ns Em user
2300properties.
2301.Bl -tag -width "-H"
2302.It Fl H
2303Do not print headers, use tab-delimited output.
2304.It Fl S Ar field
2305Sort by this field in reverse order. See
2306.Fl s .
2307.It Fl i
2308Translate SID to POSIX ID. The POSIX ID may be ephemeral if no mapping exists.
2309Normal POSIX interfaces
2310.Po for example,
2311.Xr stat 2 ,
2312.Nm ls Fl l
2313.Pc
2314perform this translation, so the
2315.Fl i
2316option allows the output from
2317.Nm zfs Cm userspace
2318to be compared directly with those utilities. However,
2319.Fl i
2320may lead to confusion if some files were created by an SMB user before a
2321SMB-to-POSIX name mapping was established. In such a case, some files will be
2322owned by the SMB entity and some by the POSIX entity. However, the
2323.Fl i
2324option will report that the POSIX entity has the total usage and quota for both.
2325.It Fl n
2326Print numeric ID instead of user/group name.
2327.It Fl o Ar field Ns Oo , Ns Ar field Oc Ns ...
2328Display only the specified fields from the following set:
2329.Sy type ,
2330.Sy name ,
2331.Sy used ,
2332.Sy quota .
2333The default is to display all fields.
2334.It Fl p
2335Use exact
2336.Pq parsable
2337numeric output.
2338.It Fl s Ar field
2339Sort output by this field. The
2340.Fl s
2341and
2342.Fl S
2343flags may be specified multiple times to sort first by one field, then by
2344another. The default is
2345.Fl s Sy type Fl s Sy name .
2346.It Fl t Ar type Ns Oo , Ns Ar type Oc Ns ...
2347Print only the specified types from the following set:
2348.Sy all ,
2349.Sy posixuser ,
2350.Sy smbuser ,
2351.Sy posixgroup ,
2352.Sy smbgroup .
2353The default is
2354.Fl t Sy posixuser Ns , Ns Sy smbuser .
2355The default can be changed to include group types.
2356.El
2357.It Xo
2358.Nm
2359.Cm groupspace
2360.Op Fl Hinp
2361.Oo Fl o Ar field Ns Oo , Ns Ar field Oc Ns ... Oc
2362.Oo Fl s Ar field Oc Ns ...
2363.Oo Fl S Ar field Oc Ns ...
2364.Oo Fl t Ar type Ns Oo , Ns Ar type Oc Ns ... Oc
2365.Ar filesystem Ns | Ns Ar snapshot
2366.Xc
2367Displays space consumed by, and quotas on, each group in the specified
2368filesystem or snapshot. This subcommand is identical to
2369.Nm zfs Cm userspace ,
2370except that the default types to display are
2371.Fl t Sy posixgroup Ns , Ns Sy smbgroup .
2372.It Xo
2373.Nm
2374.Cm mount
2375.Xc
2376Displays all ZFS file systems currently mounted.
2377.It Xo
2378.Nm
2379.Cm mount
2380.Op Fl Ov
2381.Op Fl o Ar options
2382.Fl a | Ar filesystem
2383.Xc
2384Mounts ZFS file systems.
2385.Bl -tag -width "-O"
2386.It Fl O
2387Perform an overlay mount. See
2388.Xr mount 1M
2389for more information.
2390.It Fl a
2391Mount all available ZFS file systems. Invoked automatically as part of the boot
2392process.
2393.It Ar filesystem
2394Mount the specified filesystem.
2395.It Fl o Ar options
2396An optional, comma-separated list of mount options to use temporarily for the
2397duration of the mount. See the
2398.Sx Temporary Mount Point Properties
2399section for details.
2400.It Fl v
2401Report mount progress.
2402.El
2403.It Xo
2404.Nm
2405.Cm unmount
2406.Op Fl f
2407.Fl a | Ar filesystem Ns | Ns Ar mountpoint
2408.Xc
2409Unmounts currently mounted ZFS file systems.
2410.Bl -tag -width "-a"
2411.It Fl a
2412Unmount all available ZFS file systems. Invoked automatically as part of the
2413shutdown process.
2414.It Ar filesystem Ns | Ns Ar mountpoint
2415Unmount the specified filesystem. The command can also be given a path to a ZFS
2416file system mount point on the system.
2417.It Fl f
2418Forcefully unmount the file system, even if it is currently in use.
2419.El
2420.It Xo
2421.Nm
2422.Cm share
2423.Fl a | Ar filesystem
2424.Xc
2425Shares available ZFS file systems.
2426.Bl -tag -width "-a"
2427.It Fl a
2428Share all available ZFS file systems. Invoked automatically as part of the boot
2429process.
2430.It Ar filesystem
2431Share the specified filesystem according to the
2432.Sy sharenfs
2433and
2434.Sy sharesmb
2435properties. File systems are shared when the
2436.Sy sharenfs
2437or
2438.Sy sharesmb
2439property is set.
2440.El
2441.It Xo
2442.Nm
2443.Cm unshare
2444.Fl a | Ar filesystem Ns | Ns Ar mountpoint
2445.Xc
2446Unshares currently shared ZFS file systems.
2447.Bl -tag -width "-a"
2448.It Fl a
2449Unshare all available ZFS file systems. Invoked automatically as part of the
2450shutdown process.
2451.It Ar filesystem Ns | Ns Ar mountpoint
2452Unshare the specified filesystem. The command can also be given a path to a ZFS
2453file system shared on the system.
2454.El
2455.It Xo
2456.Nm
2457.Cm bookmark
2458.Ar snapshot bookmark
2459.Xc
2460Creates a bookmark of the given snapshot. Bookmarks mark the point in time when
2461the snapshot was created, and can be used as the incremental source for a
2462.Nm zfs Cm send
2463command.
2464.Pp
2465This feature must be enabled to be used. See
2466.Xr zpool-features 5
2467for details on ZFS feature flags and the
2468.Sy bookmarks
2469feature.
2470.It Xo
2471.Nm
2472.Cm send
2473.Op Fl DLPRenpv
2474.Op Oo Fl I Ns | Ns Fl i Oc Ar snapshot
2475.Ar snapshot
2476.Xc
2477Creates a stream representation of the second
2478.Ar snapshot ,
2479which is written to standard output. The output can be redirected to a file or
2480to a different system
2481.Po for example, using
2482.Xr ssh 1
2483.Pc .
2484By default, a full stream is generated.
2485.Bl -tag -width "-D"
2486.It Fl D
2487Generate a deduplicated stream. Blocks which would have been sent multiple times
2488in the send stream will only be sent once. The receiving system must also
2489support this feature to recieve a deduplicated stream. This flag can be used
2490regardless of the dataset's
2491.Sy dedup
2492property, but performance will be much better if the filesystem uses a
2493dedup-capable checksum
2494.Po for example,
2495.Sy sha256
2496.Pc .
2497.It Fl I Ar snapshot
2498Generate a stream package that sends all intermediary snapshots from the first
2499snapshot to the second snapshot. For example,
2500.Fl I Em @a Em fs@d
2501is similar to
2502.Fl i Em @a Em fs@b Ns ; Fl i Em @b Em fs@c Ns ; Fl i Em @c Em fs@d .
2503The incremental source may be specified as with the
2504.Fl i
2505option.
2506.It Fl L
2507Generate a stream which may contain blocks larger than 128KB. This flag has no
2508effect if the
2509.Sy large_blocks
2510pool feature is disabled, or if the
2511.Sy recordsize
2512property of this filesystem has never been set above 128KB. The receiving system
2513must have the
2514.Sy large_blocks
2515pool feature enabled as well. See
2516.Xr zpool-features 5
2517for details on ZFS feature flags and the
2518.Sy large_blocks
2519feature.
2520.It Fl P
2521Print machine-parsable verbose information about the stream package generated.
2522.It Fl R
2523Generate a replication stream package, which will replicate the specified
2524file system, and all descendent file systems, up to the named snapshot. When
2525received, all properties, snapshots, descendent file systems, and clones are
2526preserved.
2527.Pp
2528If the
2529.Fl i
2530or
2531.Fl I
2532flags are used in conjunction with the
2533.Fl R
2534flag, an incremental replication stream is generated. The current values of
2535properties, and current snapshot and file system names are set when the stream
2536is received. If the
2537.Fl F
2538flag is specified when this stream is received, snapshots and file systems that
2539do not exist on the sending side are destroyed.
2540.It Fl e
2541Generate a more compact stream by using
2542.Sy WRITE_EMBEDDED
2543records for blocks which are stored more compactly on disk by the
2544.Sy embedded_data
2545pool feature. This flag has no effect if the
2546.Sy embedded_data
2547feature is disabled. The receiving system must have the
2548.Sy embedded_data
2549feature enabled. If the
2550.Sy lz4_compress
2551feature is active on the sending system, then the receiving system must have
2552that feature enabled as well. See
2553.Xr zpool-features 5
2554for details on ZFS feature flags and the
2555.Sy embedded_data
2556feature.
2557.It Fl i Ar snapshot
2558Generate an incremental stream from the first
2559.Ar snapshot
2560.Pq the incremental source
2561to the second
2562.Ar snapshot
2563.Pq the incremental target .
2564The incremental source can be specified as the last component of the snapshot
2565name
2566.Po the
2567.Sy @
2568character and following
2569.Pc
2570and it is assumed to be from the same file system as the incremental target.
2571.Pp
2572If the destination is a clone, the source may be the origin snapshot, which must
2573be fully specified
2574.Po for example,
2575.Em pool/fs@origin ,
2576not just
2577.Em @origin
2578.Pc .
2579.It Fl n
2580Do a dry-run
2581.Pq Qq No-op
2582send. Do not generate any actual send data. This is useful in conjunction with
2583the
2584.Fl v
2585or
2586.Fl P
2587flags to determine what data will be sent. In this case, the verbose output will
2588be written to standard output
2589.Po contrast with a non-dry-run, where the stream is written to standard output
2590and the verbose output goes to standard error
2591.Pc .
2592.It Fl p
2593Include the dataset's properties in the stream. This flag is implicit when
2594.Fl R
2595is specified. The receiving system must also support this feature.
2596.It Fl v
2597Print verbose information about the stream package generated. This information
2598includes a per-second report of how much data has been sent.
2599.Pp
2600The format of the stream is committed. You will be able to receive your streams
2601on future versions of ZFS .
2602.El
2603.It Xo
2604.Nm
2605.Cm send
2606.Op Fl Le
2607.Op Fl i Ar snapshot Ns | Ns Ar bookmark
2608.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2609.Xc
2610Generate a send stream, which may be of a filesystem, and may be incremental
2611from a bookmark. If the destination is a filesystem or volume, the pool must be
2612read-only, or the filesystem must not be mounted. When the stream generated from
2613a filesystem or volume is received, the default snapshot name will be
2614.Qq --head-- .
2615.Bl -tag -width "-L"
2616.It Fl L
2617Generate a stream which may contain blocks larger than 128KB. This flag has no
2618effect if the
2619.Sy large_blocks
2620pool feature is disabled, or if the
2621.Sy recordsize
2622property of this filesystem has never been set above 128KB. The receiving system
2623must have the
2624.Sy large_blocks
2625pool feature enabled as well. See
2626.Xr zpool-features 5
2627for details on ZFS feature flags and the
2628.Sy large_blocks
2629feature.
2630.It Fl e
2631Generate a more compact stream by using
2632.Sy WRITE_EMBEDDED
2633records for blocks which are stored more compactly on disk by the
2634.Sy embedded_data
2635pool feature. This flag has no effect if the
2636.Sy embedded_data
2637feature is disabled. The receiving system must have the
2638.Sy embedded_data
2639feature enabled. If the
2640.Sy lz4_compress
2641feature is active on the sending system, then the receiving system must have
2642that feature enabled as well. See
2643.Xr zpool-features 5
2644for details on ZFS feature flags and the
2645.Sy embedded_data
2646feature.
2647.It Fl i Ar snapshot Ns | Ns Ar bookmark
2648Generate an incremental send stream. The incremental source must be an earlier
2649snapshot in the destination's history. It will commonly be an earlier snapshot
2650in the destination's file system, in which case it can be specified as the last
2651component of the name
2652.Po the
2653.Sy #
2654or
2655.Sy @
2656character and following
2657.Pc .
2658.Pp
2659If the incremental target is a clone, the incremental source can be the origin
2660snapshot, or an earlier snapshot in the origin's filesystem, or the origin's
2661origin, etc.
2662.El
2663.It Xo
2664.Nm
2665.Cm send
2666.Op Fl Penv
2667.Fl t
2668.Ar receive_resume_token
2669.Xc
2670Creates a send stream which resumes an interrupted receive.  The
2671.Ar receive_resume_token
2672is the value of this property on the filesystem
2673or volume that was being received into.  See the documentation for
2674.Sy zfs receive -s
2675for more details.
2676.It Xo
2677.Nm
2678.Cm receive
2679.Op Fl Fnsuv
2680.Op Fl o Sy origin Ns = Ns Ar snapshot
2681.Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
2682.br
2683.Nm
2684.Cm receive
2685.Op Fl Fnsuv
2686.Op Fl d Ns | Ns Fl e
2687.Op Fl o Sy origin Ns = Ns Ar snapshot
2688.Ar filesystem
2689.Xc
2690Creates a snapshot whose contents are as specified in the stream provided on
2691standard input. If a full stream is received, then a new file system is created
2692as well. Streams are created using the
2693.Nm zfs Cm send
2694subcommand, which by default creates a full stream.
2695.Nm zfs Cm recv
2696can be used as an alias for
2697.Nm zfs Cm receive.
2698.Pp
2699If an incremental stream is received, then the destination file system must
2700already exist, and its most recent snapshot must match the incremental stream's
2701source. For
2702.Sy zvols ,
2703the destination device link is destroyed and recreated, which means the
2704.Sy zvol
2705cannot be accessed during the
2706.Cm receive
2707operation.
2708.Pp
2709When a snapshot replication package stream that is generated by using the
2710.Nm zfs Cm send Fl R
2711command is received, any snapshots that do not exist on the sending location are
2712destroyed by using the
2713.Nm zfs Cm destroy Fl d
2714command.
2715.Pp
2716The name of the snapshot
2717.Pq and file system, if a full stream is received
2718that this subcommand creates depends on the argument type and the use of the
2719.Fl d
2720or
2721.Fl e
2722options.
2723.Pp
2724If the argument is a snapshot name, the specified
2725.Ar snapshot
2726is created. If the argument is a file system or volume name, a snapshot with the
2727same name as the sent snapshot is created within the specified
2728.Ar filesystem
2729or
2730.Ar volume .
2731If neither of the
2732.Fl d
2733or
2734.Fl e
2735options are specified, the provided target snapshot name is used exactly as
2736provided.
2737.Pp
2738The
2739.Fl d
2740and
2741.Fl e
2742options cause the file system name of the target snapshot to be determined by
2743appending a portion of the sent snapshot's name to the specified target
2744.Ar filesystem .
2745If the
2746.Fl d
2747option is specified, all but the first element of the sent snapshot's file
2748system path
2749.Pq usually the pool name
2750is used and any required intermediate file systems within the specified one are
2751created. If the
2752.Fl e
2753option is specified, then only the last element of the sent snapshot's file
2754system name
2755.Pq i.e. the name of the source file system itself
2756is used as the target file system name.
2757.Bl -tag -width "-F"
2758.It Fl F
2759Force a rollback of the file system to the most recent snapshot before
2760performing the receive operation. If receiving an incremental replication stream
2761.Po for example, one generated by
2762.Nm zfs Cm send Fl R Op Fl i Ns | Ns Fl I
2763.Pc ,
2764destroy snapshots and file systems that do not exist on the sending side.
2765.It Fl d
2766Discard the first element of the sent snapshot's file system name, using the
2767remaining elements to determine the name of the target file system for the new
2768snapshot as described in the paragraph above.
2769.It Fl e
2770Discard all but the last element of the sent snapshot's file system name, using
2771that element to determine the name of the target file system for the new
2772snapshot as described in the paragraph above.
2773.It Fl n
2774Do not actually receive the stream. This can be useful in conjunction with the
2775.Fl v
2776option to verify the name the receive operation would use.
2777.It Fl o Sy origin Ns = Ns Ar snapshot
2778Forces the stream to be received as a clone of the given snapshot.
2779If the stream is a full send stream, this will create the filesystem
2780described by the stream as a clone of the specified snapshot. Which
2781snapshot was specified will not affect the success or failure of the
2782receive, as long as the snapshot does exist.  If the stream is an
2783incremental send stream, all the normal verification will be performed.
2784.It Fl u
2785File system that is associated with the received stream is not mounted.
2786.It Fl v
2787Print verbose information about the stream and the time required to perform the
2788receive operation.
2789.It Fl s
2790If the receive is interrupted, save the partially received state, rather
2791than deleting it.  Interruption may be due to premature termination of
2792the stream
2793.Po e.g. due to network failure or failure of the remote system
2794if the stream is being read over a network connection
2795.Pc ,
2796a checksum error in the stream, termination of the
2797.Nm zfs Cm receive
2798process, or unclean shutdown of the system.
2799.Pp
2800The receive can be resumed with a stream generated by
2801.Nm zfs Cm send Fl t Ar token ,
2802where the
2803.Ar token
2804is the value of the
2805.Sy receive_resume_token
2806property of the filesystem or volume which is received into.
2807.Pp
2808To use this flag, the storage pool must have the
2809.Sy extensible_dataset
2810feature enabled.  See
2811.Xr zpool-features 5
2812for details on ZFS feature flags.
2813.El
2814.It Xo
2815.Nm
2816.Cm receive
2817.Fl A
2818.Ar filesystem Ns | Ns Ar volume
2819.Xc
2820Abort an interrupted
2821.Nm zfs Cm receive Fl s ,
2822deleting its saved partially received state.
2823.It Xo
2824.Nm
2825.Cm allow
2826.Ar filesystem Ns | Ns Ar volume
2827.Xc
2828Displays permissions that have been delegated on the specified filesystem or
2829volume. See the other forms of
2830.Nm zfs Cm allow
2831for more information.
2832.It Xo
2833.Nm
2834.Cm allow
2835.Op Fl dglu
2836.Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
2837.Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
2838.Ar setname Oc Ns ...
2839.Ar filesystem Ns | Ns Ar volume
2840.br
2841.Nm
2842.Cm allow
2843.Op Fl dl
2844.Fl e Ns | Ns Sy everyone
2845.Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
2846.Ar setname Oc Ns ...
2847.Ar filesystem Ns | Ns Ar volume
2848.Xc
2849Delegates ZFS administration permission for the file systems to non-privileged
2850users.
2851.Bl -tag -width "-d"
2852.It Fl d
2853Allow only for the descendent file systems.
2854.It Fl e Ns | Ns Sy everyone
2855Specifies that the permissions be delegated to everyone.
2856.It Fl g Ar group Ns Oo , Ns Ar group Oc Ns ...
2857Explicitly specify that permissions are delegated to the group.
2858.It Fl l
2859Allow
2860.Qq locally
2861only for the specified file system.
2862.It Fl u Ar user Ns Oo , Ns Ar user Oc Ns ...
2863Explicitly specify that permissions are delegated to the user.
2864.It Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
2865Specifies to whom the permissions are delegated. Multiple entities can be
2866specified as a comma-separated list. If neither of the
2867.Fl gu
2868options are specified, then the argument is interpreted preferentially as the
2869keyword
2870.Sy everyone ,
2871then as a user name, and lastly as a group name. To specify a user or group
2872named
2873.Qq everyone ,
2874use the
2875.Fl g
2876or
2877.Fl u
2878options. To specify a group with the same name as a user, use the
2879.Fl g
2880options.
2881.It Xo
2882.Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
2883.Ar setname Oc Ns ...
2884.Xc
2885The permissions to delegate. Multiple permissions may be specified as a
2886comma-separated list. Permission names are the same as ZFS subcommand and
2887property names. See the property list below. Property set names,
2888which begin with
2889.Sy @ ,
2890may be specified. See the
2891.Fl s
2892form below for details.
2893.El
2894.Pp
2895If neither of the
2896.Fl dl
2897options are specified, or both are, then the permissions are allowed for the
2898file system or volume, and all of its descendents.
2899.Pp
2900Permissions are generally the ability to use a ZFS subcommand or change a ZFS
2901property. The following permissions are available:
2902.Bd -literal
2903NAME             TYPE           NOTES
2904allow            subcommand     Must also have the permission that is being
2905                                allowed
2906clone            subcommand     Must also have the 'create' ability and 'mount'
2907                                ability in the origin file system
2908create           subcommand     Must also have the 'mount' ability
2909destroy          subcommand     Must also have the 'mount' ability
2910diff             subcommand     Allows lookup of paths within a dataset
2911                                given an object number, and the ability to
2912                                create snapshots necessary to 'zfs diff'.
2913mount            subcommand     Allows mount/umount of ZFS datasets
2914promote          subcommand     Must also have the 'mount'
2915                                and 'promote' ability in the origin file system
2916receive          subcommand     Must also have the 'mount' and 'create' ability
2917rename           subcommand     Must also have the 'mount' and 'create'
2918                                ability in the new parent
2919rollback         subcommand     Must also have the 'mount' ability
2920send             subcommand
2921share            subcommand     Allows sharing file systems over NFS or SMB
2922                                protocols
2923snapshot         subcommand     Must also have the 'mount' ability
2924
2925groupquota       other          Allows accessing any groupquota@... property
2926groupused        other          Allows reading any groupused@... property
2927userprop         other          Allows changing any user property
2928userquota        other          Allows accessing any userquota@... property
2929userused         other          Allows reading any userused@... property
2930
2931aclinherit       property
2932aclmode          property
2933atime            property
2934canmount         property
2935casesensitivity  property
2936checksum         property
2937compression      property
2938copies           property
2939devices          property
2940exec             property
2941filesystem_limit property
2942mountpoint       property
2943nbmand           property
2944normalization    property
2945primarycache     property
2946quota            property
2947readonly         property
2948recordsize       property
2949refquota         property
2950refreservation   property
2951reservation      property
2952secondarycache   property
2953setuid           property
2954sharenfs         property
2955sharesmb         property
2956snapdir          property
2957snapshot_limit   property
2958utf8only         property
2959version          property
2960volblocksize     property
2961volsize          property
2962vscan            property
2963xattr            property
2964zoned            property
2965.Ed
2966.It Xo
2967.Nm
2968.Cm allow
2969.Fl c
2970.Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
2971.Ar setname Oc Ns ...
2972.Ar filesystem Ns | Ns Ar volume
2973.Xc
2974Sets
2975.Qq create time
2976permissions. These permissions are granted
2977.Pq locally
2978to the creator of any newly-created descendent file system.
2979.It Xo
2980.Nm
2981.Cm allow
2982.Fl s No @ Ns Ar setname
2983.Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
2984.Ar setname Oc Ns ...
2985.Ar filesystem Ns | Ns Ar volume
2986.Xc
2987Defines or adds permissions to a permission set. The set can be used by other
2988.Nm zfs Cm allow
2989commands for the specified file system and its descendents. Sets are evaluated
2990dynamically, so changes to a set are immediately reflected. Permission sets
2991follow the same naming restrictions as ZFS file systems, but the name must begin
2992with
2993.Sy @ ,
2994and can be no more than 64 characters long.
2995.It Xo
2996.Nm
2997.Cm unallow
2998.Op Fl dglru
2999.Ar user Ns | Ns Ar group Ns Oo , Ns Ar user Ns | Ns Ar group Oc Ns ...
3000.Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3001.Ar setname Oc Ns ... Oc
3002.Ar filesystem Ns | Ns Ar volume
3003.br
3004.Nm
3005.Cm unallow
3006.Op Fl dlr
3007.Fl e Ns | Ns Sy everyone
3008.Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3009.Ar setname Oc Ns ... Oc
3010.Ar filesystem Ns | Ns Ar volume
3011.br
3012.Nm
3013.Cm unallow
3014.Op Fl r
3015.Fl c
3016.Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3017.Ar setname Oc Ns ... Oc
3018.Ar filesystem Ns | Ns Ar volume
3019.Xc
3020Removes permissions that were granted with the
3021.Nm zfs Cm allow
3022command. No permissions are explicitly denied, so other permissions granted are
3023still in effect. For example, if the permission is granted by an ancestor. If no
3024permissions are specified, then all permissions for the specified
3025.Ar user ,
3026.Ar group ,
3027or
3028.Sy everyone
3029are removed. Specifying
3030.Sy everyone
3031.Po or using the
3032.Fl e
3033option
3034.Pc
3035only removes the permissions that were granted to everyone, not all permissions
3036for every user and group. See the
3037.Nm zfs Cm allow
3038command for a description of the
3039.Fl ldugec
3040options.
3041.Bl -tag -width "-r"
3042.It Fl r
3043Recursively remove the permissions from this file system and all descendents.
3044.El
3045.It Xo
3046.Nm
3047.Cm unallow
3048.Op Fl r
3049.Fl s @ Ns Ar setname
3050.Oo Ar perm Ns | Ns @ Ns Ar setname Ns Oo , Ns Ar perm Ns | Ns @ Ns
3051.Ar setname Oc Ns ... Oc
3052.Ar filesystem Ns | Ns Ar volume
3053.Xc
3054Removes permissions from a permission set. If no permissions are specified, then
3055all permissions are removed, thus removing the set entirely.
3056.It Xo
3057.Nm
3058.Cm hold
3059.Op Fl r
3060.Ar tag Ar snapshot Ns ...
3061.Xc
3062Adds a single reference, named with the
3063.Ar tag
3064argument, to the specified snapshot or snapshots. Each snapshot has its own tag
3065namespace, and tags must be unique within that space.
3066.Pp
3067If a hold exists on a snapshot, attempts to destroy that snapshot by using the
3068.Nm zfs Cm destroy
3069command return
3070.Er EBUSY .
3071.Bl -tag -width "-r"
3072.It Fl r
3073Specifies that a hold with the given tag is applied recursively to the snapshots
3074of all descendent file systems.
3075.El
3076.It Xo
3077.Nm
3078.Cm holds
3079.Op Fl r
3080.Ar snapshot Ns ...
3081.Xc
3082Lists all existing user references for the given snapshot or snapshots.
3083.Bl -tag -width "-r"
3084.It Fl r
3085Lists the holds that are set on the named descendent snapshots, in addition to
3086listing the holds on the named snapshot.
3087.El
3088.It Xo
3089.Nm
3090.Cm release
3091.Op Fl r
3092.Ar tag Ar snapshot Ns ...
3093.Xc
3094Removes a single reference, named with the
3095.Ar tag
3096argument, from the specified snapshot or snapshots. The tag must already exist
3097for each snapshot. If a hold exists on a snapshot, attempts to destroy that
3098snapshot by using the
3099.Nm zfs Cm destroy
3100command return
3101.Er EBUSY .
3102.Bl -tag -width "-r"
3103.It Fl r
3104Recursively releases a hold with the given tag on the snapshots of all
3105descendent file systems.
3106.El
3107.It Xo
3108.Nm
3109.Cm diff
3110.Op Fl FHt
3111.Ar snapshot Ar snapshot Ns | Ns Ar filesystem
3112.Xc
3113Display the difference between a snapshot of a given filesystem and another
3114snapshot of that filesystem from a later time or the current contents of the
3115filesystem. The first column is a character indicating the type of change, the
3116other columns indicate pathname, new pathname
3117.Pq in case of rename ,
3118change in link count, and optionally file type and/or change time. The types of
3119change are:
3120.Bd -literal
3121-       The path has been removed
3122+       The path has been created
3123M       The path has been modified
3124R       The path has been renamed
3125.Ed
3126.Bl -tag -width "-F"
3127.It Fl F
3128Display an indication of the type of file, in a manner similar to the
3129.Fl
3130option of
3131.Xr ls 1 .
3132.Bd -literal
3133B       Block device
3134C       Character device
3135/       Directory
3136>       Door
3137|       Named pipe
3138@       Symbolic link
3139P       Event port
3140=       Socket
3141F       Regular file
3142.Ed
3143.It Fl H
3144Give more parsable tab-separated output, without header lines and without
3145arrows.
3146.It Fl t
3147Display the path's inode change time as the first column of output.
3148.El
3149.El
3150.Sh EXIT STATUS
3151The
3152.Nm
3153utility exits 0 on success, 1 if an error occurs, and 2 if invalid command line
3154options were specified.
3155.Sh EXAMPLES
3156.Bl -tag -width ""
3157.It Sy Example 1 No Creating a ZFS File System Hierarchy
3158The following commands create a file system named
3159.Em pool/home
3160and a file system named
3161.Em pool/home/bob .
3162The mount point
3163.Pa /export/home
3164is set for the parent file system, and is automatically inherited by the child
3165file system.
3166.Bd -literal
3167# zfs create pool/home
3168# zfs set mountpoint=/export/home pool/home
3169# zfs create pool/home/bob
3170.Ed
3171.It Sy Example 2 No Creating a ZFS Snapshot
3172The following command creates a snapshot named
3173.Sy yesterday .
3174This snapshot is mounted on demand in the
3175.Pa .zfs/snapshot
3176directory at the root of the
3177.Em pool/home/bob
3178file system.
3179.Bd -literal
3180# zfs snapshot pool/home/bob@yesterday
3181.Ed
3182.It Sy Example 3 No Creating and Destroying Multiple Snapshots
3183The following command creates snapshots named
3184.Sy yesterday
3185of
3186.Em pool/home
3187and all of its descendent file systems. Each snapshot is mounted on demand in
3188the
3189.Pa .zfs/snapshot
3190directory at the root of its file system. The second command destroys the newly
3191created snapshots.
3192.Bd -literal
3193# zfs snapshot -r pool/home@yesterday
3194# zfs destroy -r pool/home@yesterday
3195.Ed
3196.It Sy Example 4 No Disabling and Enabling File System Compression
3197The following command disables the
3198.Sy compression
3199property for all file systems under
3200.Em pool/home .
3201The next command explicitly enables
3202.Sy compression
3203for
3204.Em pool/home/anne .
3205.Bd -literal
3206# zfs set compression=off pool/home
3207# zfs set compression=on pool/home/anne
3208.Ed
3209.It Sy Example 5 No Listing ZFS Datasets
3210The following command lists all active file systems and volumes in the system.
3211Snapshots are displayed if the
3212.Sy listsnaps
3213property is
3214.Sy on .
3215The default is
3216.Sy off .
3217See
3218.Xr zpool 1M
3219for more information on pool properties.
3220.Bd -literal
3221# zfs list
3222NAME                      USED  AVAIL  REFER  MOUNTPOINT
3223pool                      450K   457G    18K  /pool
3224pool/home                 315K   457G    21K  /export/home
3225pool/home/anne             18K   457G    18K  /export/home/anne
3226pool/home/bob             276K   457G   276K  /export/home/bob
3227.Ed
3228.It Sy Example 6 No Setting a Quota on a ZFS File System
3229The following command sets a quota of 50 Gbytes for
3230.Em pool/home/bob .
3231.Bd -literal
3232# zfs set quota=50G pool/home/bob
3233.Ed
3234.It Sy Example 7 No Listing ZFS Properties
3235The following command lists all properties for
3236.Em pool/home/bob .
3237.Bd -literal
3238# zfs get all pool/home/bob
3239NAME           PROPERTY              VALUE                  SOURCE
3240pool/home/bob  type                  filesystem             -
3241pool/home/bob  creation              Tue Jul 21 15:53 2009  -
3242pool/home/bob  used                  21K                    -
3243pool/home/bob  available             20.0G                  -
3244pool/home/bob  referenced            21K                    -
3245pool/home/bob  compressratio         1.00x                  -
3246pool/home/bob  mounted               yes                    -
3247pool/home/bob  quota                 20G                    local
3248pool/home/bob  reservation           none                   default
3249pool/home/bob  recordsize            128K                   default
3250pool/home/bob  mountpoint            /pool/home/bob         default
3251pool/home/bob  sharenfs              off                    default
3252pool/home/bob  checksum              on                     default
3253pool/home/bob  compression           on                     local
3254pool/home/bob  atime                 on                     default
3255pool/home/bob  devices               on                     default
3256pool/home/bob  exec                  on                     default
3257pool/home/bob  setuid                on                     default
3258pool/home/bob  readonly              off                    default
3259pool/home/bob  zoned                 off                    default
3260pool/home/bob  snapdir               hidden                 default
3261pool/home/bob  aclmode               discard                default
3262pool/home/bob  aclinherit            restricted             default
3263pool/home/bob  canmount              on                     default
3264pool/home/bob  xattr                 on                     default
3265pool/home/bob  copies                1                      default
3266pool/home/bob  version               4                      -
3267pool/home/bob  utf8only              off                    -
3268pool/home/bob  normalization         none                   -
3269pool/home/bob  casesensitivity       sensitive              -
3270pool/home/bob  vscan                 off                    default
3271pool/home/bob  nbmand                off                    default
3272pool/home/bob  sharesmb              off                    default
3273pool/home/bob  refquota              none                   default
3274pool/home/bob  refreservation        none                   default
3275pool/home/bob  primarycache          all                    default
3276pool/home/bob  secondarycache        all                    default
3277pool/home/bob  usedbysnapshots       0                      -
3278pool/home/bob  usedbydataset         21K                    -
3279pool/home/bob  usedbychildren        0                      -
3280pool/home/bob  usedbyrefreservation  0                      -
3281.Ed
3282.Pp
3283The following command gets a single property value.
3284.Bd -literal
3285# zfs get -H -o value compression pool/home/bob
3286on
3287.Ed
3288The following command lists all properties with local settings for
3289.Em pool/home/bob .
3290.Bd -literal
3291# zfs get -r -s local -o name,property,value all pool/home/bob
3292NAME           PROPERTY              VALUE
3293pool/home/bob  quota                 20G
3294pool/home/bob  compression           on
3295.Ed
3296.It Sy Example 8 No Rolling Back a ZFS File System
3297The following command reverts the contents of
3298.Em pool/home/anne
3299to the snapshot named
3300.Sy yesterday ,
3301deleting all intermediate snapshots.
3302.Bd -literal
3303# zfs rollback -r pool/home/anne@yesterday
3304.Ed
3305.It Sy Example 9 No Creating a ZFS Clone
3306The following command creates a writable file system whose initial contents are
3307the same as
3308.Em pool/home/bob@yesterday .
3309.Bd -literal
3310# zfs clone pool/home/bob@yesterday pool/clone
3311.Ed
3312.It Sy Example 10 No Promoting a ZFS Clone
3313The following commands illustrate how to test out changes to a file system, and
3314then replace the original file system with the changed one, using clones, clone
3315promotion, and renaming:
3316.Bd -literal
3317# zfs create pool/project/production
3318  populate /pool/project/production with data
3319# zfs snapshot pool/project/production@today
3320# zfs clone pool/project/production@today pool/project/beta
3321  make changes to /pool/project/beta and test them
3322# zfs promote pool/project/beta
3323# zfs rename pool/project/production pool/project/legacy
3324# zfs rename pool/project/beta pool/project/production
3325  once the legacy version is no longer needed, it can be destroyed
3326# zfs destroy pool/project/legacy
3327.Ed
3328.It Sy Example 11 No Inheriting ZFS Properties
3329The following command causes
3330.Em pool/home/bob
3331and
3332.Em pool/home/anne
3333to inherit the
3334.Sy checksum
3335property from their parent.
3336.Bd -literal
3337# zfs inherit checksum pool/home/bob pool/home/anne
3338.Ed
3339.It Sy Example 12 No Remotely Replicating ZFS Data
3340The following commands send a full stream and then an incremental stream to a
3341remote machine, restoring them into
3342.Em poolB/received/fs@a
3343and
3344.Em poolB/received/fs@b ,
3345respectively.
3346.Em poolB
3347must contain the file system
3348.Em poolB/received ,
3349and must not initially contain
3350.Em poolB/received/fs .
3351.Bd -literal
3352# zfs send pool/fs@a | \e
3353  ssh host zfs receive poolB/received/fs@a
3354# zfs send -i a pool/fs@b | \e
3355  ssh host zfs receive poolB/received/fs
3356.Ed
3357.It Sy Example 13 No Using the zfs receive -d Option
3358The following command sends a full stream of
3359.Em poolA/fsA/fsB@snap
3360to a remote machine, receiving it into
3361.Em poolB/received/fsA/fsB@snap .
3362The
3363.Em fsA/fsB@snap
3364portion of the received snapshot's name is determined from the name of the sent
3365snapshot.
3366.Em poolB
3367must contain the file system
3368.Em poolB/received .
3369If
3370.Em poolB/received/fsA
3371does not exist, it is created as an empty file system.
3372.Bd -literal
3373# zfs send poolA/fsA/fsB@snap | \e
3374  ssh host zfs receive -d poolB/received
3375.Ed
3376.It Sy Example 14 No Setting User Properties
3377The following example sets the user-defined
3378.Sy com.example:department
3379property for a dataset.
3380.Bd -literal
3381# zfs set com.example:department=12345 tank/accounting
3382.Ed
3383.It Sy Example 15 No Performing a Rolling Snapshot
3384The following example shows how to maintain a history of snapshots with a
3385consistent naming scheme. To keep a week's worth of snapshots, the user
3386destroys the oldest snapshot, renames the remaining snapshots, and then creates
3387a new snapshot, as follows:
3388.Bd -literal
3389# zfs destroy -r pool/users@7daysago
3390# zfs rename -r pool/users@6daysago @7daysago
3391# zfs rename -r pool/users@5daysago @6daysago
3392# zfs rename -r pool/users@yesterday @5daysago
3393# zfs rename -r pool/users@yesterday @4daysago
3394# zfs rename -r pool/users@yesterday @3daysago
3395# zfs rename -r pool/users@yesterday @2daysago
3396# zfs rename -r pool/users@today @yesterday
3397# zfs snapshot -r pool/users@today
3398.Ed
3399.It Sy Example 16 No Setting sharenfs Property Options on a ZFS File System
3400The following commands show how to set
3401.Sy sharenfs
3402property options to enable
3403.Sy rw
3404access for a set of
3405.Sy IP
3406addresses and to enable root access for system
3407.Sy neo
3408on the
3409.Em tank/home
3410file system.
3411.Bd -literal
3412# zfs set sharenfs='rw=@123.123.0.0/16,root=neo' tank/home
3413.Ed
3414.Pp
3415If you are using
3416.Sy DNS
3417for host name resolution, specify the fully qualified hostname.
3418.It Sy Example 17 No Delegating ZFS Administration Permissions on a ZFS Dataset
3419The following example shows how to set permissions so that user
3420.Sy cindys
3421can create, destroy, mount, and take snapshots on
3422.Em tank/cindys .
3423The permissions on
3424.Em tank/cindys
3425are also displayed.
3426.Bd -literal
3427# zfs allow cindys create,destroy,mount,snapshot tank/cindys
3428# zfs allow tank/cindys
3429---- Permissions on tank/cindys --------------------------------------
3430Local+Descendent permissions:
3431        user cindys create,destroy,mount,snapshot
3432.Ed
3433.Pp
3434Because the
3435.Em tank/cindys
3436mount point permission is set to 755 by default, user
3437.Sy cindys
3438will be unable to mount file systems under
3439.Em tank/cindys .
3440Add an
3441.Sy ACE
3442similar to the following syntax to provide mount point access:
3443.Bd -literal
3444# chmod A+user:cindys:add_subdirectory:allow /tank/cindys
3445.Ed
3446.It Sy Example 18 No Delegating Create Time Permissions on a ZFS Dataset
3447The following example shows how to grant anyone in the group
3448.Sy staff
3449to create file systems in
3450.Em tank/users .
3451This syntax also allows staff members to destroy their own file systems, but not
3452destroy anyone else's file system. The permissions on
3453.Em tank/users
3454are also displayed.
3455.Bd -literal
3456# zfs allow staff create,mount tank/users
3457# zfs allow -c destroy tank/users
3458# zfs allow tank/users
3459---- Permissions on tank/users ---------------------------------------
3460Permission sets:
3461        destroy
3462Local+Descendent permissions:
3463        group staff create,mount
3464.Ed
3465.It Sy Example 19 No Defining and Granting a Permission Set on a ZFS Dataset
3466The following example shows how to define and grant a permission set on the
3467.Em tank/users
3468file system. The permissions on
3469.Em tank/users
3470are also displayed.
3471.Bd -literal
3472# zfs allow -s @pset create,destroy,snapshot,mount tank/users
3473# zfs allow staff @pset tank/users
3474# zfs allow tank/users
3475---- Permissions on tank/users ---------------------------------------
3476Permission sets:
3477        @pset create,destroy,mount,snapshot
3478Local+Descendent permissions:
3479        group staff @pset
3480.Ed
3481.It Sy Example 20 No Delegating Property Permissions on a ZFS Dataset
3482The following example shows to grant the ability to set quotas and reservations
3483on the
3484.Em users/home
3485file system. The permissions on
3486.Em users/home
3487are also displayed.
3488.Bd -literal
3489# zfs allow cindys quota,reservation users/home
3490# zfs allow users/home
3491---- Permissions on users/home ---------------------------------------
3492Local+Descendent permissions:
3493        user cindys quota,reservation
3494cindys% zfs set quota=10G users/home/marks
3495cindys% zfs get quota users/home/marks
3496NAME              PROPERTY  VALUE  SOURCE
3497users/home/marks  quota     10G    local
3498.Ed
3499.It Sy Example 21 No Removing ZFS Delegated Permissions on a ZFS Dataset
3500The following example shows how to remove the snapshot permission from the
3501.Sy staff
3502group on the
3503.Em tank/users
3504file system. The permissions on
3505.Em tank/users
3506are also displayed.
3507.Bd -literal
3508# zfs unallow staff snapshot tank/users
3509# zfs allow tank/users
3510---- Permissions on tank/users ---------------------------------------
3511Permission sets:
3512        @pset create,destroy,mount,snapshot
3513Local+Descendent permissions:
3514        group staff @pset
3515.Ed
3516.It Sy Example 22 No Showing the differences between a snapshot and a ZFS Dataset
3517The following example shows how to see what has changed between a prior
3518snapshot of a ZFS dataset and its current state. The
3519.Fl F
3520option is used to indicate type information for the files affected.
3521.Bd -literal
3522# zfs diff -F tank/test@before tank/test
3523M       /       /tank/test/
3524M       F       /tank/test/linked      (+1)
3525R       F       /tank/test/oldname -> /tank/test/newname
3526-       F       /tank/test/deleted
3527+       F       /tank/test/created
3528M       F       /tank/test/modified
3529.Ed
3530.El
3531.Sh INTERFACE STABILITY
3532.Sy Commited .
3533.Sh SEE ALSO
3534.Xr gzip 1 ,
3535.Xr ssh 1 ,
3536.Xr mount 1M ,
3537.Xr share 1M ,
3538.Xr sharemgr 1M ,
3539.Xr unshare 1M ,
3540.Xr zonecfg 1M ,
3541.Xr zpool 1M ,
3542.Xr chmod 2 ,
3543.Xr stat 2 ,
3544.Xr write 2 ,
3545.Xr fsync 3C ,
3546.Xr dfstab 4 ,
3547.Xr acl 5 ,
3548.Xr attributes 5
3549