1 ZFS(1M) Maintenance Commands ZFS(1M)
2
3 NAME
4 zfs configures ZFS file systems
5
6 SYNOPSIS
7 zfs [-?]
8 zfs create [-p] [-o property=value]... filesystem
9 zfs create [-ps] [-b blocksize] [-o property=value]... -V size volume
10 zfs destroy [-Rfnprv] filesystem|volume
11 zfs destroy [-Rdnprv] filesystem|volume@snap[%snap[,snap[%snap]]]...
12 zfs destroy filesystem|volume#bookmark
13 zfs snapshot [-r] [-o property=value]...
14 filesystem@snapname|volume@snapname...
15 zfs rollback [-Rfr] snapshot
16 zfs clone [-p] [-o property=value]... snapshot filesystem|volume
17 zfs promote clone-filesystem
18 zfs rename [-f] filesystem|volume|snapshot filesystem|volume|snapshot
19 zfs rename [-fp] filesystem|volume filesystem|volume
20 zfs rename -r snapshot snapshot
21 zfs list [-r|-d depth] [-Hp] [-o property[,property]...] [-s property]...
22 [-S property]... [-t type[,type]...] [filesystem|volume|snapshot]...
23 zfs set property=value [property=value]... filesystem|volume|snapshot...
24 zfs get [-r|-d depth] [-Hp] [-o field[,field]...] [-s source[,source]...]
25 [-t type[,type]...] all | property[,property]...
26 filesystem|volume|snapshot...
27 zfs inherit [-rS] property filesystem|volume|snapshot...
28 zfs upgrade
29 zfs upgrade -v
30 zfs upgrade [-r] [-V version] -a | filesystem
31 zfs userspace [-Hinp] [-o field[,field]...] [-s field]... [-S field]...
32 [-t type[,type]...] filesystem|snapshot
33 zfs groupspace [-Hinp] [-o field[,field]...] [-s field]... [-S field]...
34 [-t type[,type]...] filesystem|snapshot
35 zfs mount
36 zfs mount [-Ov] [-o options] -a | filesystem
37 zfs unmount [-f] -a | filesystem|mountpoint
38 zfs share -a | filesystem
39 zfs unshare -a | filesystem|mountpoint
40 zfs bookmark snapshot bookmark
41 zfs send [-DLPRenpv] [[-I|-i] snapshot] snapshot
42 zfs send [-Le] [-i snapshot|bookmark] filesystem|volume|snapshot
43 zfs send [-Penv] -t receive_resume_token
44 zfs receive [-Fnsuv] [-o origin=snapshot] filesystem|volume|snapshot
45 zfs receive [-Fnsuv] [-d|-e] [-o origin=snapshot] filesystem
46 zfs receive -A filesystem|volume
47 zfs allow filesystem|volume
48 zfs allow [-dglu] user|group[,user|group]...
49 perm|@setname[,perm|@setname]... filesystem|volume
50 zfs allow [-dl] -e|everyone perm|@setname[,perm|@setname]...
51 filesystem|volume
52 zfs allow -c perm|@setname[,perm|@setname]... filesystem|volume
53 zfs allow -s @setname perm|@setname[,perm|@setname]... filesystem|volume
54 zfs unallow [-dglru] user|group[,user|group]...
55 [perm|@setname[,perm|@setname]...] filesystem|volume
56 zfs unallow [-dlr] -e|everyone [perm|@setname[,perm|@setname]...]
57 filesystem|volume
58 zfs unallow [-r] -c [perm|@setname[,perm|@setname]...] filesystem|volume
59 zfs unallow [-r] -s -@setname [perm|@setname[,perm|@setname]...]
60 filesystem|volume
61 zfs hold [-r] tag snapshot...
62 zfs holds [-r] snapshot...
63 zfs release [-r] tag snapshot...
64 zfs diff [-FHt] snapshot snapshot|filesystem
65
66 DESCRIPTION
67 The zfs command configures ZFS datasets within a ZFS storage pool, as
68 described in zpool(1M). A dataset is identified by a unique path within
69 the ZFS namespace. For example:
70
71 pool/{filesystem,volume,snapshot}
72
73 where the maximum length of a dataset name is MAXNAMELEN (256 bytes).
74
75 A dataset can be one of the following:
76
77 file system A ZFS dataset of type filesystem can be mounted within the
78 standard system namespace and behaves like other file
79 systems. While ZFS file systems are designed to be POSIX
80 compliant, known issues exist that prevent compliance in
81 some cases. Applications that depend on standards
82 conformance might fail due to non-standard behavior when
83 checking file system free space.
84
85 volume A logical volume exported as a raw or block device. This
86 type of dataset should only be used under special
87 circumstances. File systems are typically used in most
88 environments.
89
90 snapshot A read-only version of a file system or volume at a given
91 point in time. It is specified as filesystem@name or
92 volume@name.
93
94 ZFS File System Hierarchy
95 A ZFS storage pool is a logical collection of devices that provide space
96 for datasets. A storage pool is also the root of the ZFS file system
97 hierarchy.
98
99 The root of the pool can be accessed as a file system, such as mounting
100 and unmounting, taking snapshots, and setting properties. The physical
101 storage characteristics, however, are managed by the zpool(1M) command.
102
103 See zpool(1M) for more information on creating and administering pools.
104
105 Snapshots
106 A snapshot is a read-only copy of a file system or volume. Snapshots can
107 be created extremely quickly, and initially consume no additional space
108 within the pool. As data within the active dataset changes, the snapshot
109 consumes more data than would otherwise be shared with the active
110 dataset.
111
112 Snapshots can have arbitrary names. Snapshots of volumes can be cloned or
113 rolled back, but cannot be accessed independently.
114
115 File system snapshots can be accessed under the .zfs/snapshot directory
116 in the root of the file system. Snapshots are automatically mounted on
117 demand and may be unmounted at regular intervals. The visibility of the
118 .zfs directory can be controlled by the snapdir property.
119
120 Clones
121 A clone is a writable volume or file system whose initial contents are
122 the same as another dataset. As with snapshots, creating a clone is
123 nearly instantaneous, and initially consumes no additional space.
124
125 Clones can only be created from a snapshot. When a snapshot is cloned, it
126 creates an implicit dependency between the parent and child. Even though
127 the clone is created somewhere else in the dataset hierarchy, the
128 original snapshot cannot be destroyed as long as a clone exists. The
129 origin property exposes this dependency, and the destroy command lists
130 any such dependencies, if they exist.
131
132 The clone parent-child dependency relationship can be reversed by using
133 the promote subcommand. This causes the "origin" file system to become a
134 clone of the specified file system, which makes it possible to destroy
135 the file system that the clone was created from.
136
137 Mount Points
138 Creating a ZFS file system is a simple operation, so the number of file
139 systems per system is likely to be numerous. To cope with this, ZFS
140 automatically manages mounting and unmounting file systems without the
141 need to edit the /etc/vfstab file. All automatically managed file systems
142 are mounted by ZFS at boot time.
143
144 By default, file systems are mounted under /path, where path is the name
145 of the file system in the ZFS namespace. Directories are created and
146 destroyed as needed.
147
148 A file system can also have a mount point set in the mountpoint property.
149 This directory is created as needed, and ZFS automatically mounts the
150 file system when the zfs mount -a command is invoked (without editing
151 /etc/vfstab). The mountpoint property can be inherited, so if pool/home
152 has a mount point of /export/stuff, then pool/home/user automatically
153 inherits a mount point of /export/stuff/user.
154
155 A file system mountpoint property of none prevents the file system from
156 being mounted.
157
158 If needed, ZFS file systems can also be managed with traditional tools
159 (mount, umount, /etc/vfstab). If a file system's mount point is set to
160 legacy, ZFS makes no attempt to manage the file system, and the
161 administrator is responsible for mounting and unmounting the file system.
162
163 Zones
164 A ZFS file system can be added to a non-global zone by using the zonecfg
165 add fs subcommand. A ZFS file system that is added to a non-global zone
166 must have its mountpoint property set to legacy.
167
168 The physical properties of an added file system are controlled by the
169 global administrator. However, the zone administrator can create, modify,
170 or destroy files within the added file system, depending on how the file
171 system is mounted.
172
173 A dataset can also be delegated to a non-global zone by using the zonecfg
174 add dataset subcommand. You cannot delegate a dataset to one zone and the
175 children of the same dataset to another zone. The zone administrator can
176 change properties of the dataset or any of its children. However, the
177 quota, filesystem_limit and snapshot_limit properties of the delegated
178 dataset can be modified only by the global administrator.
179
180 A ZFS volume can be added as a device to a non-global zone by using the
181 zonecfg add device subcommand. However, its physical properties can be
182 modified only by the global administrator.
183
184 For more information about zonecfg syntax, see zonecfg(1M).
185
186 After a dataset is delegated to a non-global zone, the zoned property is
187 automatically set. A zoned file system cannot be mounted in the global
188 zone, since the zone administrator might have to set the mount point to
189 an unacceptable value.
190
191 The global administrator can forcibly clear the zoned property, though
192 this should be done with extreme care. The global administrator should
193 verify that all the mount points are acceptable before clearing the
194 property.
195
196 Native Properties
197 Properties are divided into two types, native properties and user-defined
198 (or "user") properties. Native properties either export internal
199 statistics or control ZFS behavior. In addition, native properties are
200 either editable or read-only. User properties have no effect on ZFS
201 behavior, but you can use them to annotate datasets in a way that is
202 meaningful in your environment. For more information about user
203 properties, see the User Properties section, below.
204
205 Every dataset has a set of properties that export statistics about the
206 dataset as well as control various behaviors. Properties are inherited
207 from the parent unless overridden by the child. Some properties apply
208 only to certain types of datasets (file systems, volumes, or snapshots).
209
210 The values of numeric properties can be specified using human-readable
211 suffixes (for example, k, KB, M, Gb, and so forth, up to Z for
212 zettabyte). The following are all valid (and equal) specifications:
213 1536M, 1.5g, 1.50GB.
214
215 The values of non-numeric properties are case sensitive and must be
216 lowercase, except for mountpoint, sharenfs, and sharesmb.
217
218 The following native properties consist of read-only statistics about the
219 dataset. These properties can be neither set, nor inherited. Native
220 properties apply to all dataset types unless otherwise noted.
221
222 available The amount of space available to the dataset and
223 all its children, assuming that there is no other
224 activity in the pool. Because space is shared
225 within a pool, availability can be limited by any
226 number of factors, including physical pool size,
227 quotas, reservations, or other datasets within the
228 pool.
229
230 This property can also be referred to by its
231 shortened column name, avail.
232
233 compressratio For non-snapshots, the compression ratio achieved
234 for the used space of this dataset, expressed as a
235 multiplier. The used property includes descendant
236 datasets, and, for clones, does not include the
237 space shared with the origin snapshot. For
238 snapshots, the compressratio is the same as the
239 refcompressratio property. Compression can be
240 turned on by running: zfs set compression=on
241 dataset. The default value is off.
242
243 creation The time this dataset was created.
244
245 clones For snapshots, this property is a comma-separated
246 list of filesystems or volumes which are clones of
247 this snapshot. The clones' origin property is this
248 snapshot. If the clones property is not empty, then
249 this snapshot can not be destroyed (even with the
250 -r or -f options).
251
252 defer_destroy This property is on if the snapshot has been marked
253 for deferred destroy by using the zfs destroy -d
254 command. Otherwise, the property is off.
255
256 filesystem_count The total number of filesystems and volumes that
257 exist under this location in the dataset tree. This
258 value is only available when a filesystem_limit has
259 been set somewhere in the tree under which the
260 dataset resides.
261
262 logicalreferenced The amount of space that is "logically" accessible
263 by this dataset. See the referenced property. The
264 logical space ignores the effect of the compression
265 and copies properties, giving a quantity closer to
266 the amount of data that applications see. However,
267 it does include space consumed by metadata.
268
269 This property can also be referred to by its
270 shortened column name, lrefer.
271
272 logicalused The amount of space that is "logically" consumed by
273 this dataset and all its descendents. See the used
274 property. The logical space ignores the effect of
275 the compression and copies properties, giving a
276 quantity closer to the amount of data that
277 applications see. However, it does include space
278 consumed by metadata.
279
280 This property can also be referred to by its
281 shortened column name, lused.
282
283 mounted For file systems, indicates whether the file system
284 is currently mounted. This property can be either
285 yes or no.
286
287 origin For cloned file systems or volumes, the snapshot
288 from which the clone was created. See also the
289 clones property.
290
291 receive_resume_token For filesystems or volumes which have saved
292 partially-completed state from zfs receive -s, this
293 opaque token can be provided to zfs send -t to
294 resume and complete the zfs receive.
295
296 referenced The amount of data that is accessible by this
297 dataset, which may or may not be shared with other
298 datasets in the pool. When a snapshot or clone is
299 created, it initially references the same amount of
300 space as the file system or snapshot it was created
301 from, since its contents are identical.
302
303 This property can also be referred to by its
304 shortened column name, refer.
305
306 refcompressratio The compression ratio achieved for the referenced
307 space of this dataset, expressed as a multiplier.
308 See also the compressratio property.
309
310 snapshot_count The total number of snapshots that exist under this
311 location in the dataset tree. This value is only
312 available when a snapshot_limit has been set
313 somewhere in the tree under which the dataset
314 resides.
315
316 type The type of dataset: filesystem, volume, or
317 snapshot.
318
319 used The amount of space consumed by this dataset and
320 all its descendents. This is the value that is
321 checked against this dataset's quota and
322 reservation. The space used does not include this
323 dataset's reservation, but does take into account
324 the reservations of any descendent datasets. The
325 amount of space that a dataset consumes from its
326 parent, as well as the amount of space that are
327 freed if this dataset is recursively destroyed, is
328 the greater of its space used and its reservation.
329
330 When snapshots (see the Snapshots section) are
331 created, their space is initially shared between
332 the snapshot and the file system, and possibly with
333 previous snapshots. As the file system changes,
334 space that was previously shared becomes unique to
335 the snapshot, and counted in the snapshot's space
336 used. Additionally, deleting snapshots can increase
337 the amount of space unique to (and used by) other
338 snapshots.
339
340 The amount of space used, available, or referenced
341 does not take into account pending changes. Pending
342 changes are generally accounted for within a few
343 seconds. Committing a change to a disk using
344 fsync(3C) or O_SYNC does not necessarily guarantee
345 that the space usage information is updated
346 immediately.
347
348 usedby* The usedby* properties decompose the used
349 properties into the various reasons that space is
350 used. Specifically, used = usedbychildren +
351 usedbydataset + usedbyrefreservation +
352 usedbysnapshots. These properties are only
353 available for datasets created on zpool "version
354 13" pools.
355
356 usedbychildren The amount of space used by children of this
357 dataset, which would be freed if all the dataset's
358 children were destroyed.
359
360 usedbydataset The amount of space used by this dataset itself,
361 which would be freed if the dataset were destroyed
362 (after first removing any refreservation and
363 destroying any necessary snapshots or descendents).
364
365 usedbyrefreservation The amount of space used by a refreservation set on
366 this dataset, which would be freed if the
367 refreservation was removed.
368
369 usedbysnapshots The amount of space consumed by snapshots of this
370 dataset. In particular, it is the amount of space
371 that would be freed if all of this dataset's
372 snapshots were destroyed. Note that this is not
373 simply the sum of the snapshots' used properties
374 because space can be shared by multiple snapshots.
375
376 userused@user The amount of space consumed by the specified user
377 in this dataset. Space is charged to the owner of
378 each file, as displayed by ls -l. The amount of
379 space charged is displayed by du and ls -s. See
380 the zfs userspace subcommand for more information.
381
382 Unprivileged users can access only their own space
383 usage. The root user, or a user who has been
384 granted the userused privilege with zfs allow, can
385 access everyone's usage.
386
387 The userused@... properties are not displayed by
388 zfs get all. The user's name must be appended
389 after the @ symbol, using one of the following
390 forms:
391
392 POSIX name (for example, joe)
393
394 POSIX numeric ID (for example, 789)
395
396 SID name (for example, joe.smith@mydomain)
397
398 SID numeric ID (for example, S-1-123-456-789)
399
400 userrefs This property is set to the number of user holds on
401 this snapshot. User holds are set by using the zfs
402 hold command.
403
404 groupused@group The amount of space consumed by the specified group
405 in this dataset. Space is charged to the group of
406 each file, as displayed by ls -l. See the
407 userused@user property for more information.
408
409 Unprivileged users can only access their own
410 groups' space usage. The root user, or a user who
411 has been granted the groupused privilege with zfs
412 allow, can access all groups' usage.
413
414 volblocksize=blocksize
415 For volumes, specifies the block size of the
416 volume. The blocksize cannot be changed once the
417 volume has been written, so it should be set at
418 volume creation time. The default blocksize for
419 volumes is 8 Kbytes. Any power of 2 from 512 bytes
420 to 128 Kbytes is valid.
421
422 This property can also be referred to by its
423 shortened column name, volblock.
424
425 written The amount of referenced space written to this
426 dataset since the previous snapshot.
427
428 written@snapshot The amount of referenced space written to this
429 dataset since the specified snapshot. This is the
430 space that is referenced by this dataset but was
431 not referenced by the specified snapshot.
432
433 The snapshot may be specified as a short snapshot
434 name (just the part after the @), in which case it
435 will be interpreted as a snapshot in the same
436 filesystem as this dataset. The snapshot may be a
437 full snapshot name (filesystem@snapshot), which for
438 clones may be a snapshot in the origin's filesystem
439 (or the origin of the origin's filesystem, etc.)
440
441 The following native properties can be used to change the behavior of a
442 ZFS dataset.
443
444 aclinherit=discard|noallow|restricted|passthrough|passthrough-x
445 Controls how ACEs are inherited when files and directories are created.
446
447 discard does not inherit any ACEs.
448
449 noallow only inherits inheritable ACEs that specify "deny"
450 permissions.
451
452 restricted default, removes the write_acl and write_owner
453 permissions when the ACE is inherited.
454
455 passthrough inherits all inheritable ACEs without any modifications.
456
457 passthrough-x same meaning as passthrough, except that the owner@,
458 group@, and everyone@ ACEs inherit the execute
459 permission only if the file creation mode also requests
460 the execute bit.
461
462 When the property value is set to passthrough, files are created with a
463 mode determined by the inheritable ACEs. If no inheritable ACEs exist
464 that affect the mode, then the mode is set in accordance to the
465 requested mode from the application.
466
467 aclmode=discard|groupmask|passthrough|restricted
468 Controls how an ACL is modified during chmod(2).
469
470 discard default, deletes all ACEs that do not represent the mode
471 of the file.
472
473 groupmask reduces permissions granted in all ALLOW entries found in
474 the ACL such that they are no greater than the group
475 permissions specified by chmod(2).
476
477 passthrough indicates that no changes are made to the ACL other than
478 creating or updating the necessary ACEs to represent the
479 new mode of the file or directory.
480
481 restricted causes the chmod(2) operation to return an error when used
482 on any file or directory which has a non-trivial ACEs whose
483 entries can not be represented by a mode.
484
485 chmod(2) is required to change the set user ID, set group ID, or sticky
486 bits on a file or directory, as they do not have equivalent ACEs. In
487 order to use chmod(2) on a file or directory with a non-trivial ACL when
488 aclmode is set to restricted, you must first remove all ACEs which do
489 not represent the current mode.
490
491 atime=on|off
492 Controls whether the access time for files is updated when they are
493 read. Turning this property off avoids producing write traffic when
494 reading files and can result in significant performance gains, though
495 it might confuse mailers and other similar utilities. The default value
496 is on.
497
498 canmount=on|off|noauto
499 If this property is set to off, the file system cannot be mounted, and
500 is ignored by zfs mount -a. Setting this property to off is similar to
501 setting the mountpoint property to none, except that the dataset still
502 has a normal mountpoint property, which can be inherited. Setting this
503 property to off allows datasets to be used solely as a mechanism to
504 inherit properties. One example of setting canmount=off is to have two
505 datasets with the same mountpoint, so that the children of both
506 datasets appear in the same directory, but might have different
507 inherited characteristics.
508
509 When set to noauto, a dataset can only be mounted and unmounted
510 explicitly. The dataset is not mounted automatically when the dataset
511 is created or imported, nor is it mounted by the zfs mount -a command
512 or unmounted by the zfs unmount -a command.
513
514 This property is not inherited.
515
516 checksum=on|off|fletcher2|fletcher4|sha256|noparity|sha512|skein|edonr
517 Controls the checksum used to verify data integrity. The default value
518 is on, which automatically selects an appropriate algorithm (currently,
519 fletcher4, but this may change in future releases). The value off
520 disables integrity checking on user data. The value noparity not only
521 disables integrity but also disables maintaining parity for user data.
522 This setting is used internally by a dump device residing on a RAID-Z
523 pool and should not be used by any other dataset. Disabling checksums
524 is NOT a recommended practice.
525
526 The sha512, skein, and edonr checksum algorithms require enabling the
527 appropriate features on the pool. Please see zpool-features(5) for more
528 information on these algorithms.
529
530 Changing this property affects only newly-written data.
531
532 compression=on|off|gzip|gzip-N|lz4|lzjb|zle
533 Controls the compression algorithm used for this dataset.
534
535 Setting compression to on indicates that the current default
536 compression algorithm should be used. The default balances compression
537 and decompression speed, with compression ratio and is expected to work
538 well on a wide variety of workloads. Unlike all other settings for
539 this property, on does not select a fixed compression type. As new
540 compression algorithms are added to ZFS and enabled on a pool, the
541 default compression algorithm may change. The current default
542 compression algorthm is either lzjb or, if the lz4_compress feature is
543 enabled, lz4.
544
545 The lz4 compression algorithm is a high-performance replacement for the
546 lzjb algorithm. It features significantly faster compression and
547 decompression, as well as a moderately higher compression ratio than
548 lzjb, but can only be used on pools with the lz4_compress feature set
549 to enabled. See zpool-features(5) for details on ZFS feature flags and
550 the lz4_compress feature.
551
552 The lzjb compression algorithm is optimized for performance while
553 providing decent data compression.
554
555 The gzip compression algorithm uses the same compression as the gzip(1)
556 command. You can specify the gzip level by using the value gzip-N,
557 where N is an integer from 1 (fastest) to 9 (best compression ratio).
558 Currently, gzip is equivalent to gzip-6 (which is also the default for
559 gzip(1)).
560
561 The zle compression algorithm compresses runs of zeros.
562
563 This property can also be referred to by its shortened column name
564 compress. Changing this property affects only newly-written data.
565
566 copies=1|2|3
567 Controls the number of copies of data stored for this dataset. These
568 copies are in addition to any redundancy provided by the pool, for
569 example, mirroring or RAID-Z. The copies are stored on different disks,
570 if possible. The space used by multiple copies is charged to the
571 associated file and dataset, changing the used property and counting
572 against quotas and reservations.
573
574 Changing this property only affects newly-written data. Therefore, set
575 this property at file system creation time by using the -o copies=N
576 option.
577
578 devices=on|off
579 Controls whether device nodes can be opened on this file system. The
580 default value is on.
581
582 exec=on|off
583 Controls whether processes can be executed from within this file
584 system. The default value is on.
585
586 filesystem_limit=count|none
587 Limits the number of filesystems and volumes that can exist under this
588 point in the dataset tree. The limit is not enforced if the user is
589 allowed to change the limit. Setting a filesystem_limit to on a
590 descendent of a filesystem that already has a filesystem_limit does not
591 override the ancestor's filesystem_limit, but rather imposes an
592 additional limit. This feature must be enabled to be used (see
593 zpool-features(5)).
594
595 fsid_guid=value
596 Sets the dataset fsid_guid. The fsid_guid is a 64-bit unsigned integer,
597 used to construct the vfs id when mounting a dataset. This property
598 should only be set if you need the vfs id to be identical on two
599 systems, for example in a NFS migration scenario. When the fsid_guid
600 is changed for a file system, the file system and any children that
601 inherit the mountpoint are unmounted, then remounted. If the file
602 system was shared, existing NFS clients will require a remount.
603
604 mountpoint=path|none|legacy
605 Controls the mount point used for this file system. See the Mount
606 Points section for more information on how this property is used.
607
608 When the mountpoint property is changed for a file system, the file
609 system and any children that inherit the mount point are unmounted. If
610 the new value is legacy, then they remain unmounted. Otherwise, they
611 are automatically remounted in the new location if the property was
612 previously legacy or none, or if they were mounted before the property
613 was changed. In addition, any shared file systems are unshared and
614 shared in the new location.
615
616 nbmand=on|off
617 Controls whether the file system should be mounted with nbmand (Non
618 Blocking mandatory locks). This is used for SMB clients. Changes to
619 this property only take effect when the file system is umounted and
620 remounted. See mount(1M) for more information on nbmand mounts.
621
622 primarycache=all|none|metadata
623 Controls what is cached in the primary cache (ARC). If this property
624 is set to all, then both user data and metadata is cached. If this
625 property is set to none, then neither user data nor metadata is cached.
626 If this property is set to metadata, then only metadata is cached. The
627 default value is all.
628
629 quota=size|none
630 Limits the amount of space a dataset and its descendents can consume.
631 This property enforces a hard limit on the amount of space used. This
632 includes all space consumed by descendents, including file systems and
633 snapshots. Setting a quota on a descendent of a dataset that already
634 has a quota does not override the ancestor's quota, but rather imposes
635 an additional limit.
636
637 Quotas cannot be set on volumes, as the volsize property acts as an
638 implicit quota.
639
640 snapshot_limit=count|none
641 Limits the number of snapshots that can be created on a dataset and its
642 descendents. Setting a snapshot_limit on a descendent of a dataset that
643 already has a snapshot_limit does not override the ancestor's
644 snapshot_limit, but rather imposes an additional limit. The limit is
645 not enforced if the user is allowed to change the limit. For example,
646 this means that recursive snapshots taken from the global zone are
647 counted against each delegated dataset within a zone. This feature must
648 be enabled to be used (see zpool-features(5)).
649
650 userquota@user=size|none
651 Limits the amount of space consumed by the specified user. User space
652 consumption is identified by the userspace@user property.
653
654 Enforcement of user quotas may be delayed by several seconds. This
655 delay means that a user might exceed their quota before the system
656 notices that they are over quota and begins to refuse additional writes
657 with the EDQUOT error message. See the zfs userspace subcommand for
658 more information.
659
660 Unprivileged users can only access their own groups' space usage. The
661 root user, or a user who has been granted the userquota privilege with
662 zfs allow, can get and set everyone's quota.
663
664 This property is not available on volumes, on file systems before
665 version 4, or on pools before version 15. The userquota@... properties
666 are not displayed by zfs get all. The user's name must be appended
667 after the @ symbol, using one of the following forms:
668
669 POSIX name (for example, joe)
670
671 POSIX numeric ID (for example, 789)
672
673 SID name (for example, joe.smith@mydomain)
674
675 SID numeric ID (for example, S-1-123-456-789)
676
677 groupquota@group=size|none
678 Limits the amount of space consumed by the specified group. Group space
679 consumption is identified by the groupused@group property.
680
681 Unprivileged users can access only their own groups' space usage. The
682 root user, or a user who has been granted the groupquota privilege with
683 zfs allow, can get and set all groups' quotas.
684
685 readonly=on|off
686 Controls whether this dataset can be modified. The default value is
687 off.
688
689 This property can also be referred to by its shortened column name,
690 rdonly.
691
692 recordsize=size
693 Specifies a suggested block size for files in the file system. This
694 property is designed solely for use with database workloads that access
695 files in fixed-size records. ZFS automatically tunes block sizes
696 according to internal algorithms optimized for typical access patterns.
697
698 For databases that create very large files but access them in small
699 random chunks, these algorithms may be suboptimal. Specifying a
700 recordsize greater than or equal to the record size of the database can
701 result in significant performance gains. Use of this property for
702 general purpose file systems is strongly discouraged, and may adversely
703 affect performance.
704
705 The size specified must be a power of two greater than or equal to 512
706 and less than or equal to 128 Kbytes. If the large_blocks feature is
707 enabled on the pool, the size may be up to 1 Mbyte. See
708 zpool-features(5) for details on ZFS feature flags.
709
710 Changing the file system's recordsize affects only files created
711 afterward; existing files are unaffected.
712
713 This property can also be referred to by its shortened column name,
714 recsize.
715
716 redundant_metadata=all|most
717 Controls what types of metadata are stored redundantly. ZFS stores an
718 extra copy of metadata, so that if a single block is corrupted, the
719 amount of user data lost is limited. This extra copy is in addition to
720 any redundancy provided at the pool level (e.g. by mirroring or
721 RAID-Z), and is in addition to an extra copy specified by the copies
722 property (up to a total of 3 copies). For example if the pool is
723 mirrored, copies=2, and redundant_metadata=most, then ZFS stores 6
724 copies of most metadata, and 4 copies of data and some metadata.
725
726 When set to all, ZFS stores an extra copy of all metadata. If a single
727 on-disk block is corrupt, at worst a single block of user data (which is
728 recordsize bytes long) can be lost.
729
730 When set to most, ZFS stores an extra copy of most types of metadata.
731 This can improve performance of random writes, because less metadata
732 must be written. In practice, at worst about 100 blocks (of recordsize
733 bytes each) of user data can be lost if a single on-disk block is
734 corrupt. The exact behavior of which metadata blocks are stored
735 redundantly may change in future releases.
736
737 The default value is all.
738
739 refquota=size|none
740 Limits the amount of space a dataset can consume. This property
741 enforces a hard limit on the amount of space used. This hard limit does
742 not include space used by descendents, including file systems and
743 snapshots.
744
745 refreservation=size|none
746 The minimum amount of space guaranteed to a dataset, not including its
747 descendents. When the amount of space used is below this value, the
748 dataset is treated as if it were taking up the amount of space
749 specified by refreservation. The refreservation reservation is
750 accounted for in the parent datasets' space used, and counts against
751 the parent datasets' quotas and reservations.
752
753 If refreservation is set, a snapshot is only allowed if there is enough
754 free pool space outside of this reservation to accommodate the current
755 number of "referenced" bytes in the dataset.
756
757 This property can also be referred to by its shortened column name,
758 refreserv.
759
760 reservation=size|none
761 The minimum amount of space guaranteed to a dataset and its
762 descendents. When the amount of space used is below this value, the
763 dataset is treated as if it were taking up the amount of space
764 specified by its reservation. Reservations are accounted for in the
765 parent datasets' space used, and count against the parent datasets'
766 quotas and reservations.
767
768 This property can also be referred to by its shortened column name,
769 reserv.
770
771 secondarycache=all|none|metadata
772 Controls what is cached in the secondary cache (L2ARC). If this
773 property is set to all, then both user data and metadata is cached. If
774 this property is set to none, then neither user data nor metadata is
775 cached. If this property is set to metadata, then only metadata is
776 cached. The default value is all.
777
778 setuid=on|off
779 Controls whether the setuid bit is respected for the file system. The
780 default value is on.
781
782 sharesmb=on|off|opts
783 Controls whether the file system is shared via SMB, and what options
784 are to be used. A file system with the sharesmb property set to off is
785 managed through traditional tools such as sharemgr(1M). Otherwise, the
786 file system is automatically shared and unshared with the zfs share and
787 zfs unshare commands. If the property is set to on, the sharemgr(1M)
788 command is invoked with no options. Otherwise, the sharemgr(1M) command
789 is invoked with options equivalent to the contents of this property.
790
791 Because SMB shares requires a resource name, a unique resource name is
792 constructed from the dataset name. The constructed name is a copy of
793 the dataset name except that the characters in the dataset name, which
794 would be illegal in the resource name, are replaced with underscore (_)
795 characters. A pseudo property "name" is also supported that allows you
796 to replace the data set name with a specified name. The specified name
797 is then used to replace the prefix dataset in the case of inheritance.
798 For example, if the dataset data/home/john is set to name=john, then
799 data/home/john has a resource name of john. If a child dataset
800 data/home/john/backups is shared, it has a resource name of
801 john_backups.
802
803 When SMB shares are created, the SMB share name appears as an entry in
804 the .zfs/shares directory. You can use the ls or chmod command to
805 display the share-level ACLs on the entries in this directory.
806
807 When the sharesmb property is changed for a dataset, the dataset and
808 any children inheriting the property are re-shared with the new options,
809 only if the property was previously set to off, or if they were shared
810 before the property was changed. If the new property is set to off, the
811 file systems are unshared.
812
813 sharenfs=on|off|opts
814 Controls whether the file system is shared via NFS, and what options
815 are to be used. A file system with a sharenfs property of off is
816 managed through traditional tools such as share(1M), unshare(1M), and
817 dfstab(4). Otherwise, the file system is automatically shared and
818 unshared with the zfs share and zfs unshare commands. If the property
819 is set to on, share(1M) command is invoked with no options. Otherwise,
820 the share(1M) command is invoked with options equivalent to the
821 contents of this property.
822
823 When the sharenfs property is changed for a dataset, the dataset and
824 any children inheriting the property are re-shared with the new options,
825 only if the property was previously off, or if they were shared before
826 the property was changed. If the new property is off, the file systems
827 are unshared.
828
829 logbias=latency|throughput
830 Provide a hint to ZFS about handling of synchronous requests in this
831 dataset. If logbias is set to latency (the default), ZFS will use pool
832 log devices (if configured) to handle the requests at low latency. If
833 logbias is set to throughput, ZFS will not use configured pool log
834 devices. ZFS will instead optimize synchronous operations for global
835 pool throughput and efficient use of resources.
836
837 snapdir=hidden|visible
838 Controls whether the .zfs directory is hidden or visible in the root of
839 the file system as discussed in the Snapshots section. The default
840 value is hidden.
841
842 sync=standard|always|disabled
843 Controls the behavior of synchronous requests (e.g. fsync, O_DSYNC).
844 standard is the POSIX specified behavior of ensuring all synchronous
845 requests are written to stable storage and all devices are flushed to
846 ensure data is not cached by device controllers (this is the default).
847 always causes every file system transaction to be written and flushed
848 before its system call returns. This has a large performance penalty.
849 disabled disables synchronous requests. File system transactions are
850 only committed to stable storage periodically. This option will give
851 the highest performance. However, it is very dangerous as ZFS would be
852 ignoring the synchronous transaction demands of applications such as
853 databases or NFS. Administrators should only use this option when the
854 risks are understood.
855
856 version=N|current
857 The on-disk version of this file system, which is independent of the
858 pool version. This property can only be set to later supported
859 versions. See the zfs upgrade command.
860
861 volsize=size
862 For volumes, specifies the logical size of the volume. By default,
863 creating a volume establishes a reservation of equal size. For storage
864 pools with a version number of 9 or higher, a refreservation is set
865 instead. Any changes to volsize are reflected in an equivalent change
866 to the reservation (or refreservation). The volsize can only be set to
867 a multiple of volblocksize, and cannot be zero.
868
869 The reservation is kept equal to the volume's logical size to prevent
870 unexpected behavior for consumers. Without the reservation, the volume
871 could run out of space, resulting in undefined behavior or data
872 corruption, depending on how the volume is used. These effects can also
873 occur when the volume size is changed while it is in use (particularly
874 when shrinking the size). Extreme care should be used when adjusting
875 the volume size.
876
877 Though not recommended, a "sparse volume" (also known as "thin
878 provisioning") can be created by specifying the -s option to the zfs
879 create -V command, or by changing the reservation after the volume has
880 been created. A "sparse volume" is a volume where the reservation is
881 less then the volume size. Consequently, writes to a sparse volume can
882 fail with ENOSPC when the pool is low on space. For a sparse volume,
883 changes to volsize are not reflected in the reservation.
884
885 vscan=on|off
886 Controls whether regular files should be scanned for viruses when a
887 file is opened and closed. In addition to enabling this property, the
888 virus scan service must also be enabled for virus scanning to occur.
889 The default value is off.
890
891 xattr=on|off
892 Controls whether extended attributes are enabled for this file system.
893 The default value is on.
894
895 zoned=on|off
896 Controls whether the dataset is managed from a non-global zone. See the
897 Zones section for more information. The default value is off.
898
899 The following three properties cannot be changed after the file system is
900 created, and therefore, should be set when the file system is created. If
901 the properties are not set with the zfs create or zpool create commands,
902 these properties are inherited from the parent dataset. If the parent
903 dataset lacks these properties due to having been created prior to these
904 features being supported, the new file system will have the default
905 values for these properties.
906
907 casesensitivity=sensitive|insensitive|mixed
908 Indicates whether the file name matching algorithm used by the file
909 system should be case-sensitive, case-insensitive, or allow a combination
910 of both styles of matching. The default value for the casesensitivity
911 property is sensitive. Traditionally, UNIX and POSIX file systems have
912 case-sensitive file names.
913
914 The mixed value for the casesensitivity property indicates that the
915 file system can support requests for both case-sensitive and case-
916 insensitive matching behavior. Currently, case-insensitive matching
917 behavior on a file system that supports mixed behavior is limited to
918 the SMB server product. For more information about the mixed value
919 behavior, see the "ZFS Administration Guide".
920
921 normalization=none|formC|formD|formKC|formKD
922 Indicates whether the file system should perform a unicode
923 normalization of file names whenever two file names are compared, and
924 which normalization algorithm should be used. File names are always
925 stored unmodified, names are normalized as part of any comparison
926 process. If this property is set to a legal value other than none, and
927 the utf8only property was left unspecified, the utf8only property is
928 automatically set to on. The default value of the normalization
929 property is none. This property cannot be changed after the file
930 system is created.
931
932 utf8only=on|off
933 Indicates whether the file system should reject file names that include
934 characters that are not present in the UTF-8 character code set. If
935 this property is explicitly set to off, the normalization property must
936 either not be explicitly set or be set to none. The default value for
937 the utf8only property is off. This property cannot be changed after
938 the file system is created.
939
940 The casesensitivity, normalization, and utf8only properties are also new
941 permissions that can be assigned to non-privileged users by using the ZFS
942 delegated administration feature.
943
944 Temporary Mount Point Properties
945 When a file system is mounted, either through mount(1M) for legacy mounts
946 or the zfs mount command for normal file systems, its mount options are
947 set according to its properties. The correlation between properties and
948 mount options is as follows:
949
950 PROPERTY MOUNT OPTION
951 devices devices/nodevices
952 exec exec/noexec
953 readonly ro/rw
954 setuid setuid/nosetuid
955 xattr xattr/noxattr
956
957 In addition, these options can be set on a per-mount basis using the -o
958 option, without affecting the property that is stored on disk. The values
959 specified on the command line override the values stored in the dataset.
960 The nosuid option is an alias for nodevices,nosetuid. These properties
961 are reported as "temporary" by the zfs get command. If the properties are
962 changed while the dataset is mounted, the new setting overrides any
963 temporary settings.
964
965 User Properties
966 In addition to the standard native properties, ZFS supports arbitrary
967 user properties. User properties have no effect on ZFS behavior, but
968 applications or administrators can use them to annotate datasets (file
969 systems, volumes, and snapshots).
970
971 User property names must contain a colon (:) character to distinguish
972 them from native properties. They may contain lowercase letters, numbers,
973 and the following punctuation characters: colon (":"), dash ("-"), period
974 ("."), and underscore ("_"). The expected convention is that the
975 property name is divided into two portions such as module:property, but
976 this namespace is not enforced by ZFS. User property names can be at
977 most 256 characters, and cannot begin with a dash ("-").
978
979 When making programmatic use of user properties, it is strongly suggested
980 to use a reversed DNS domain name for the module component of property
981 names to reduce the chance that two independently-developed packages use
982 the same property name for different purposes.
983
984 The values of user properties are arbitrary strings, are always
985 inherited, and are never validated. All of the commands that operate on
986 properties (zfs list, zfs get, zfs set, and so forth) can be used to
987 manipulate both native properties and user properties. Use the zfs
988 inherit command to clear a user property . If the property is not defined
989 in any parent dataset, it is removed entirely. Property values are
990 limited to 1024 characters.
991
992 ZFS Volumes as Swap or Dump Devices
993 During an initial installation a swap device and dump device are created
994 on ZFS volumes in the ZFS root pool. By default, the swap area size is
995 based on 1/2 the size of physical memory up to 2 Gbytes. The size of the
996 dump device depends on the kernel's requirements at installation time.
997 Separate ZFS volumes must be used for the swap area and dump devices. Do
998 not swap to a file on a ZFS file system. A ZFS swap file configuration is
999 not supported.
1000
1001 If you need to change your swap area or dump device after the system is
1002 installed or upgraded, use the swap(1M) and dumpadm(1M) commands.
1003
1004 SUBCOMMANDS
1005 All subcommands that modify state are logged persistently to the pool in
1006 their original form.
1007
1008 zfs -?
1009 Displays a help message.
1010
1011 zfs create [-p] [-o property=value]... filesystem
1012 Creates a new ZFS file system. The file system is automatically mounted
1013 according to the mountpoint property inherited from the parent.
1014
1015 -o property=value
1016 Sets the specified property as if the command zfs set
1017 property=value was invoked at the same time the dataset was
1018 created. Any editable ZFS property can also be set at creation
1019 time. Multiple -o options can be specified. An error results if the
1020 same property is specified in multiple -o options.
1021
1022 -p Creates all the non-existing parent datasets. Datasets created in
1023 this manner are automatically mounted according to the mountpoint
1024 property inherited from their parent. Any property specified on the
1025 command line using the -o option is ignored. If the target
1026 filesystem already exists, the operation completes successfully.
1027
1028 zfs create [-ps] [-b blocksize] [-o property=value]... -V size volume
1029 Creates a volume of the given size. The volume is exported as a block
1030 device in /dev/zvol/{dsk,rdsk}/path, where path is the name of the
1031 volume in the ZFS namespace. The size represents the logical size as
1032 exported by the device. By default, a reservation of equal size is
1033 created.
1034
1035 size is automatically rounded up to the nearest 128 Kbytes to ensure
1036 that the volume has an integral number of blocks regardless of
1037 blocksize.
1038
1039 -b blocksize
1040 Equivalent to -o volblocksize=blocksize. If this option is
1041 specified in conjunction with -o volblocksize, the resulting
1042 behavior is undefined.
1043
1044 -o property=value
1045 Sets the specified property as if the zfs set property=value
1046 command was invoked at the same time the dataset was created. Any
1047 editable ZFS property can also be set at creation time. Multiple -o
1048 options can be specified. An error results if the same property is
1049 specified in multiple -o options.
1050
1051 -p Creates all the non-existing parent datasets. Datasets created in
1052 this manner are automatically mounted according to the mountpoint
1053 property inherited from their parent. Any property specified on the
1054 command line using the -o option is ignored. If the target
1055 filesystem already exists, the operation completes successfully.
1056
1057 -s Creates a sparse volume with no reservation. See volsize in the
1058 Native Properties section for more information about sparse
1059 volumes.
1060
1061 zfs destroy [-Rfnprv] filesystem|volume
1062 Destroys the given dataset. By default, the command unshares any file
1063 systems that are currently shared, unmounts any file systems that are
1064 currently mounted, and refuses to destroy a dataset that has active
1065 dependents (children or clones).
1066
1067 -R Recursively destroy all dependents, including cloned file systems
1068 outside the target hierarchy.
1069
1070 -f Force an unmount of any file systems using the unmount -f command.
1071 This option has no effect on non-file systems or unmounted file
1072 systems.
1073
1074 -n Do a dry-run ("No-op") deletion. No data will be deleted. This is
1075 useful in conjunction with the -v or -p flags to determine what
1076 data would be deleted.
1077
1078 -p Print machine-parsable verbose information about the deleted data.
1079
1080 -r Recursively destroy all children.
1081
1082 -v Print verbose information about the deleted data.
1083
1084 Extreme care should be taken when applying either the -r or the -R
1085 options, as they can destroy large portions of a pool and cause
1086 unexpected behavior for mounted file systems in use.
1087
1088 zfs destroy [-Rdnprv] filesystem|volume@snap[%snap[,snap[%snap]]]...
1089 The given snapshots are destroyed immediately if and only if the zfs
1090 destroy command without the -d option would have destroyed it. Such
1091 immediate destruction would occur, for example, if the snapshot had no
1092 clones and the user-initiated reference count were zero.
1093
1094 If a snapshot does not qualify for immediate destruction, it is marked
1095 for deferred deletion. In this state, it exists as a usable, visible
1096 snapshot until both of the preconditions listed above are met, at which
1097 point it is destroyed.
1098
1099 An inclusive range of snapshots may be specified by separating the
1100 first and last snapshots with a percent sign. The first and/or last
1101 snapshots may be left blank, in which case the filesystem's oldest or
1102 newest snapshot will be implied.
1103
1104 Multiple snapshots (or ranges of snapshots) of the same filesystem or
1105 volume may be specified in a comma-separated list of snapshots. Only the
1106 snapshot's short name (the part after the @) should be specified when
1107 using a range or comma-separated list to identify multiple snapshots.
1108
1109 -R Recursively destroy all clones of these snapshots, including the
1110 clones, snapshots, and children. If this flag is specified, the -d
1111 flag will have no effect.
1112
1113 -d Defer snapshot deletion.
1114
1115 -n Do a dry-run ("No-op") deletion. No data will be deleted. This is
1116 useful in conjunction with the -p or -v flags to determine what
1117 data would be deleted.
1118
1119 -p Print machine-parsable verbose information about the deleted data.
1120
1121 -r Destroy (or mark for deferred deletion) all snapshots with this
1122 name in descendent file systems.
1123
1124 -v Print verbose information about the deleted data.
1125
1126 Extreme care should be taken when applying either the -r or the -R
1127 options, as they can destroy large portions of a pool and cause
1128 unexpected behavior for mounted file systems in use.
1129
1130 zfs destroy filesystem|volume#bookmark
1131 The given bookmark is destroyed.
1132
1133 zfs snapshot [-r] [-o property=value]...
1134 filesystem@snapname|volume@snapname...
1135 Creates snapshots with the given names. All previous modifications by
1136 successful system calls to the file system are part of the snapshots.
1137 Snapshots are taken atomically, so that all snapshots correspond to the
1138 same moment in time. See the Snapshots section for details.
1139
1140 -o property=value
1141 Sets the specified property; see zfs create for details.
1142
1143 -r Recursively create snapshots of all descendent datasets
1144
1145 zfs rollback [-Rfr] snapshot
1146 Roll back the given dataset to a previous snapshot. When a dataset is
1147 rolled back, all data that has changed since the snapshot is discarded,
1148 and the dataset reverts to the state at the time of the snapshot. By
1149 default, the command refuses to roll back to a snapshot other than the
1150 most recent one. In order to do so, all intermediate snapshots and
1151 bookmarks must be destroyed by specifying the -r option.
1152
1153 The -rR options do not recursively destroy the child snapshots of a
1154 recursive snapshot. Only direct snapshots of the specified filesystem
1155 are destroyed by either of these options. To completely roll back a
1156 recursive snapshot, you must rollback the individual child snapshots.
1157
1158 -R Destroy any more recent snapshots and bookmarks, as well as any
1159 clones of those snapshots.
1160
1161 -f Used with the -R option to force an unmount of any clone file
1162 systems that are to be destroyed.
1163
1164 -r Destroy any snapshots and bookmarks more recent than the one
1165 specified.
1166
1167 zfs clone [-p] [-o property=value]... snapshot filesystem|volume
1168 Creates a clone of the given snapshot. See the Clones section for
1169 details. The target dataset can be located anywhere in the ZFS
1170 hierarchy, and is created as the same type as the original.
1171
1172 -o property=value
1173 Sets the specified property; see zfs create for details.
1174
1175 -p Creates all the non-existing parent datasets. Datasets created in
1176 this manner are automatically mounted according to the mountpoint
1177 property inherited from their parent. If the target filesystem or
1178 volume already exists, the operation completes successfully.
1179
1180 zfs promote clone-filesystem
1181 Promotes a clone file system to no longer be dependent on its "origin"
1182 snapshot. This makes it possible to destroy the file system that the
1183 clone was created from. The clone parent-child dependency relationship
1184 is reversed, so that the origin file system becomes a clone of the
1185 specified file system.
1186
1187 The snapshot that was cloned, and any snapshots previous to this
1188 snapshot, are now owned by the promoted clone. The space they use moves
1189 from the origin file system to the promoted clone, so enough space must
1190 be available to accommodate these snapshots. No new space is consumed
1191 by this operation, but the space accounting is adjusted. The promoted
1192 clone must not have any conflicting snapshot names of its own. The
1193 rename subcommand can be used to rename any conflicting snapshots.
1194
1195 zfs rename [-f] filesystem|volume|snapshot filesystem|volume|snapshot
1196 zfs rename [-fp] filesystem|volume filesystem|volume
1197 Renames the given dataset. The new target can be located anywhere in
1198 the ZFS hierarchy, with the exception of snapshots. Snapshots can only
1199 be renamed within the parent file system or volume. When renaming a
1200 snapshot, the parent file system of the snapshot does not need to be
1201 specified as part of the second argument. Renamed file systems can
1202 inherit new mount points, in which case they are unmounted and
1203 remounted at the new mount point.
1204
1205 -f Force unmount any filesystems that need to be unmounted in the
1206 process.
1207
1208 -p Creates all the nonexistent parent datasets. Datasets created in
1209 this manner are automatically mounted according to the mountpoint
1210 property inherited from their parent.
1211
1212 zfs rename -r snapshot snapshot
1213 Recursively rename the snapshots of all descendent datasets. Snapshots
1214 are the only dataset that can be renamed recursively.
1215
1216 zfs list [-r|-d depth] [-Hp] [-o property[,property]...] [-s property]...
1217 [-S property]... [-t type[,type]...] [filesystem|volume|snapshot]...
1218 Lists the property information for the given datasets in tabular form.
1219 If specified, you can list property information by the absolute
1220 pathname or the relative pathname. By default, all file systems and
1221 volumes are displayed. Snapshots are displayed if the listsnaps
1222 property is on (the default is off). The following fields are
1223 displayed, name,used,available,referenced,mountpoint.
1224
1225 -H Used for scripting mode. Do not print headers and separate fields
1226 by a single tab instead of arbitrary white space.
1227
1228 -S property
1229 Same as the -s option, but sorts by property in descending order.
1230
1231 -d depth
1232 Recursively display any children of the dataset, limiting the
1233 recursion to
1234
1235 -o property
1236 A comma-separated list of properties to display. The property must
1237 be:
1238
1239 One of the properties described in the Native Properties
1240 section
1241
1242 A user property
1243
1244 The value name to display the dataset name
1245
1246 The value space to display space usage properties on file
1247 systems and volumes. This is a shortcut for specifying -o
1248 name,avail,used,usedsnap,usedds,usedrefreserv,usedchild -t
1249 filesystem,volume syntax.
1250
1251 -p Display numbers in parsable (exact) values.
1252
1253 -r Recursively display any children of the dataset on the command
1254 line. depth. A depth of 1 will display only the dataset and its
1255 direct children.
1256
1257 -s property
1258 A property for sorting the output by column in ascending order
1259 based on the value of the property. The property must be one of the
1260 properties described in the Properties section, or the special
1261 value name to sort by the dataset name. Multiple properties can be
1262 specified at one time using multiple -s property options. Multiple
1263 -s options are evaluated from left to right in decreasing order of
1264 importance. The following is a list of sorting criteria:
1265
1266 Numeric types sort in numeric order.
1267
1268 String types sort in alphabetical order.
1269
1270 Types inappropriate for a row sort that row to the literal
1271 bottom, regardless of the specified ordering.
1272
1273 If no sorting options are specified the existing behavior of zfs
1274 list is preserved.
1275
1276 -t type
1277 A comma-separated list of types to display, where type is one of
1278 filesystem, snapshot, volume, bookmark, or all. For example,
1279 specifying -t snapshot displays only snapshots.
1280
1281 zfs set property=value [property=value]... filesystem|volume|snapshot...
1282 Sets the property or list of properties to the given value(s) for each
1283 dataset. Only some properties can be edited. See the Properties
1284 section for more information on what properties can be set and
1285 acceptable values. Numeric values can be specified as exact values, or
1286 in a human-readable form with a suffix of B, K, M, G, T, P, E, Z (for
1287 bytes, kilobytes, megabytes, gigabytes, terabytes, petabytes, exabytes,
1288 or zettabytes, respectively). User properties can be set on snapshots.
1289 For more information, see the User Properties section.
1290
1291 zfs get [-r|-d depth] [-Hp] [-o field[,field]...] [-s source[,source]...]
1292 [-t type[,type]...] all | property[,property]...
1293 filesystem|volume|snapshot...
1294 Displays properties for the given datasets. If no datasets are
1295 specified, then the command displays properties for all datasets on the
1296 system. For each property, the following columns are displayed:
1297
1298 name Dataset name
1299 property Property name
1300 value Property value
1301 source Property source. Can either be local, default,
1302 temporary, inherited, or none (-).
1303
1304 All columns are displayed by default, though this can be controlled by
1305 using the -o option. This command takes a comma-separated list of
1306 properties as described in the Native Properties and User Properties
1307 sections.
1308
1309 The special value all can be used to display all properties that apply
1310 to the given dataset's type (filesystem, volume, snapshot, or
1311 bookmark).
1312
1313 -H Display output in a form more easily parsed by scripts. Any headers
1314 are omitted, and fields are explicitly separated by a single tab
1315 instead of an arbitrary amount of space.
1316
1317 -d depth
1318 Recursively display any children of the dataset, limiting the
1319 recursion to depth. A depth of 1 will display only the dataset and
1320 its direct children.
1321
1322 -o field
1323 A comma-separated list of columns to display.
1324 name,property,value,source is the default value.
1325
1326 -p Display numbers in parsable (exact) values.
1327
1328 -r Recursively display properties for any children.
1329
1330 -s source
1331 A comma-separated list of sources to display. Those properties
1332 coming from a source other than those in this list are ignored.
1333 Each source must be one of the following: local, default,
1334 inherited, temporary, and none. The default value is all sources.
1335
1336 -t type
1337 A comma-separated list of types to display, where type is one of
1338 filesystem, snapshot, volume, bookmark, or all.
1339
1340 zfs inherit [-rS] property filesystem|volume|snapshot...
1341 Clears the specified property, causing it to be inherited from an
1342 ancestor, restored to default if no ancestor has the property set, or
1343 with the -S option reverted to the received value if one exists. See
1344 the Properties section for a listing of default values, and details on
1345 which properties can be inherited.
1346
1347 -r Recursively inherit the given property for all children.
1348
1349 -S Revert the property to the received value if one exists; otherwise
1350 operate as if the -S option was not specified.
1351
1352 zfs upgrade
1353 Displays a list of file systems that are not the most recent version.
1354
1355 zfs upgrade -v
1356 Displays a list of currently supported file system versions.
1357
1358 zfs upgrade [-r] [-V version] -a | filesystem
1359 Upgrades file systems to a new on-disk version. Once this is done, the
1360 file systems will no longer be accessible on systems running older
1361 versions of the software. zfs send streams generated from new
1362 snapshots of these file systems cannot be accessed on systems running
1363 older versions of the software.
1364
1365 In general, the file system version is independent of the pool version.
1366 See zpool(1M) for information on the zpool upgrade command.
1367
1368 In some cases, the file system version and the pool version are
1369 interrelated and the pool version must be upgraded before the file
1370 system version can be upgraded.
1371
1372 -V version
1373 Upgrade to the specified version. If the -V flag is not specified,
1374 this command upgrades to the most recent version. This option can
1375 only be used to increase the version number, and only up to the
1376 most recent version supported by this software.
1377
1378 -a Upgrade all file systems on all imported pools.
1379
1380 filesystem
1381 Upgrade the specified file system.
1382
1383 -r Upgrade the specified file system and all descendent file systems.
1384
1385 zfs userspace [-Hinp] [-o field[,field]...] [-s field]... [-S field]...
1386 [-t type[,type]...] filesystem|snapshot
1387 Displays space consumed by, and quotas on, each user in the specified
1388 filesystem or snapshot. This corresponds to the userused@user and
1389 userquota@user properties.
1390
1391 -H Do not print headers, use tab-delimited output.
1392
1393 -S field
1394 Sort by this field in reverse order. See -s.
1395
1396 -i Translate SID to POSIX ID. The POSIX ID may be ephemeral if no
1397 mapping exists. Normal POSIX interfaces (for example, stat(2), ls
1398 -l) perform this translation, so the -i option allows the output
1399 from zfs userspace to be compared directly with those utilities.
1400 However, -i may lead to confusion if some files were created by an
1401 SMB user before a SMB-to-POSIX name mapping was established. In such
1402 a case, some files will be owned by the SMB entity and some by the
1403 POSIX entity. However, the -i option will report that the POSIX
1404 entity has the total usage and quota for both.
1405
1406 -n Print numeric ID instead of user/group name.
1407
1408 -o field[,field]...
1409 Display only the specified fields from the following set: type,
1410 name, used, quota. The default is to display all fields.
1411
1412 -p Use exact (parsable) numeric output.
1413
1414 -s field
1415 Sort output by this field. The -s and -S flags may be specified
1416 multiple times to sort first by one field, then by another. The
1417 default is -s type -s name.
1418
1419 -t type[,type]...
1420 Print only the specified types from the following set: all,
1421 posixuser, smbuser, posixgroup, smbgroup. The default is -t
1422 posixuser,smbuser. The default can be changed to include group
1423 types.
1424
1425 zfs groupspace [-Hinp] [-o field[,field]...] [-s field]... [-S field]...
1426 [-t type[,type]...] filesystem|snapshot
1427 Displays space consumed by, and quotas on, each group in the specified
1428 filesystem or snapshot. This subcommand is identical to zfs userspace,
1429 except that the default types to display are -t posixgroup,smbgroup.
1430
1431 zfs mount
1432 Displays all ZFS file systems currently mounted.
1433
1434 zfs mount [-Ov] [-o options] -a | filesystem
1435 Mounts ZFS file systems.
1436
1437 -O Perform an overlay mount. See mount(1M) for more information.
1438
1439 -a Mount all available ZFS file systems. Invoked automatically as part
1440 of the boot process.
1441
1442 filesystem
1443 Mount the specified filesystem.
1444
1445 -o options
1446 An optional, comma-separated list of mount options to use
1447 temporarily for the duration of the mount. See the Temporary Mount
1448 Point Properties section for details.
1449
1450 -v Report mount progress.
1451
1452 zfs unmount [-f] -a | filesystem|mountpoint
1453 Unmounts currently mounted ZFS file systems.
1454
1455 -a Unmount all available ZFS file systems. Invoked automatically as
1456 part of the shutdown process.
1457
1458 filesystem|mountpoint
1459 Unmount the specified filesystem. The command can also be given a
1460 path to a ZFS file system mount point on the system.
1461
1462 -f Forcefully unmount the file system, even if it is currently in use.
1463
1464 zfs share -a | filesystem
1465 Shares available ZFS file systems.
1466
1467 -a Share all available ZFS file systems. Invoked automatically as part
1468 of the boot process.
1469
1470 filesystem
1471 Share the specified filesystem according to the sharenfs and
1472 sharesmb properties. File systems are shared when the sharenfs or
1473 sharesmb property is set.
1474
1475 zfs unshare -a | filesystem|mountpoint
1476 Unshares currently shared ZFS file systems.
1477
1478 -a Unshare all available ZFS file systems. Invoked automatically as
1479 part of the shutdown process.
1480
1481 filesystem|mountpoint
1482 Unshare the specified filesystem. The command can also be given a
1483 path to a ZFS file system shared on the system.
1484
1485 zfs bookmark snapshot bookmark
1486 Creates a bookmark of the given snapshot. Bookmarks mark the point in
1487 time when the snapshot was created, and can be used as the incremental
1488 source for a zfs send command.
1489
1490 This feature must be enabled to be used. See zpool-features(5) for
1491 details on ZFS feature flags and the bookmarks feature.
1492
1493 zfs send [-DLPRenpv] [[-I|-i] snapshot] snapshot
1494 Creates a stream representation of the second snapshot, which is
1495 written to standard output. The output can be redirected to a file or
1496 to a different system (for example, using ssh(1)). By default, a full
1497 stream is generated.
1498
1499 -D Generate a deduplicated stream. Blocks which would have been sent
1500 multiple times in the send stream will only be sent once. The
1501 receiving system must also support this feature to recieve a
1502 deduplicated stream. This flag can be used regardless of the
1503 dataset's dedup property, but performance will be much better if
1504 the filesystem uses a dedup-capable checksum (for example, sha256).
1505
1506 -I snapshot
1507 Generate a stream package that sends all intermediary snapshots
1508 from the first snapshot to the second snapshot. For example, -I @a
1509 fs@d is similar to -i @a fs@b; -i @b fs@c; -i @c fs@d. The
1510 incremental source may be specified as with the -i option.
1511
1512 -L Generate a stream which may contain blocks larger than 128KB. This
1513 flag has no effect if the large_blocks pool feature is disabled, or
1514 if the recordsize property of this filesystem has never been set
1515 above 128KB. The receiving system must have the large_blocks pool
1516 feature enabled as well. See zpool-features(5) for details on ZFS
1517 feature flags and the large_blocks feature.
1518
1519 -P Print machine-parsable verbose information about the stream package
1520 generated.
1521
1522 -R Generate a replication stream package, which will replicate the
1523 specified file system, and all descendent file systems, up to the
1524 named snapshot. When received, all properties, snapshots,
1525 descendent file systems, and clones are preserved.
1526
1527 If the -i or -I flags are used in conjunction with the -R flag, an
1528 incremental replication stream is generated. The current values of
1529 properties, and current snapshot and file system names are set when
1530 the stream is received. If the -F flag is specified when this
1531 stream is received, snapshots and file systems that do not exist on
1532 the sending side are destroyed.
1533
1534 -e Generate a more compact stream by using WRITE_EMBEDDED records for
1535 blocks which are stored more compactly on disk by the embedded_data
1536 pool feature. This flag has no effect if the embedded_data feature
1537 is disabled. The receiving system must have the embedded_data
1538 feature enabled. If the lz4_compress feature is active on the
1539 sending system, then the receiving system must have that feature
1540 enabled as well. See zpool-features(5) for details on ZFS feature
1541 flags and the embedded_data feature.
1542
1543 -i snapshot
1544 Generate an incremental stream from the first snapshot (the
1545 incremental source) to the second snapshot (the incremental
1546 target). The incremental source can be specified as the last
1547 component of the snapshot name (the @ character and following) and
1548 it is assumed to be from the same file system as the incremental
1549 target.
1550
1551 If the destination is a clone, the source may be the origin
1552 snapshot, which must be fully specified (for example,
1553 pool/fs@origin, not just @origin).
1554
1555 -n Do a dry-run ("No-op") send. Do not generate any actual send data.
1556 This is useful in conjunction with the -v or -P flags to determine
1557 what data will be sent. In this case, the verbose output will be
1558 written to standard output (contrast with a non-dry-run, where the
1559 stream is written to standard output and the verbose output goes to
1560 standard error).
1561
1562 -p Include the dataset's properties in the stream. This flag is
1563 implicit when -R is specified. The receiving system must also
1564 support this feature.
1565
1566 -v Print verbose information about the stream package generated. This
1567 information includes a per-second report of how much data has been
1568 sent.
1569
1570 The format of the stream is committed. You will be able to receive
1571 your streams on future versions of ZFS .
1572
1573 zfs send [-Le] [-i snapshot|bookmark] filesystem|volume|snapshot
1574 Generate a send stream, which may be of a filesystem, and may be
1575 incremental from a bookmark. If the destination is a filesystem or
1576 volume, the pool must be read-only, or the filesystem must not be
1577 mounted. When the stream generated from a filesystem or volume is
1578 received, the default snapshot name will be "--head--".
1579
1580 -L Generate a stream which may contain blocks larger than 128KB. This
1581 flag has no effect if the large_blocks pool feature is disabled, or
1582 if the recordsize property of this filesystem has never been set
1583 above 128KB. The receiving system must have the large_blocks pool
1584 feature enabled as well. See zpool-features(5) for details on ZFS
1585 feature flags and the large_blocks feature.
1586
1587 -e Generate a more compact stream by using WRITE_EMBEDDED records for
1588 blocks which are stored more compactly on disk by the embedded_data
1589 pool feature. This flag has no effect if the embedded_data feature
1590 is disabled. The receiving system must have the embedded_data
1591 feature enabled. If the lz4_compress feature is active on the
1592 sending system, then the receiving system must have that feature
1593 enabled as well. See zpool-features(5) for details on ZFS feature
1594 flags and the embedded_data feature.
1595
1596 -i snapshot|bookmark
1597 Generate an incremental send stream. The incremental source must be
1598 an earlier snapshot in the destination's history. It will commonly
1599 be an earlier snapshot in the destination's file system, in which
1600 case it can be specified as the last component of the name (the #
1601 or @ character and following).
1602
1603 If the incremental target is a clone, the incremental source can be
1604 the origin snapshot, or an earlier snapshot in the origin's
1605 filesystem, or the origin's origin, etc.
1606
1607 zfs send [-Penv] -t receive_resume_token
1608 Creates a send stream which resumes an interrupted receive. The
1609 receive_resume_token is the value of this property on the filesystem or
1610 volume that was being received into. See the documentation for zfs
1611 receive -s for more details.
1612
1613 zfs receive [-Fnsuv] [-o origin=snapshot] filesystem|volume|snapshot
1614 zfs receive [-Fnsuv] [-d|-e] [-o origin=snapshot] filesystem
1615 Creates a snapshot whose contents are as specified in the stream
1616 provided on standard input. If a full stream is received, then a new
1617 file system is created as well. Streams are created using the zfs send
1618 subcommand, which by default creates a full stream. zfs recv can be
1619 used as an alias for zfs receive.
1620
1621 If an incremental stream is received, then the destination file system
1622 must already exist, and its most recent snapshot must match the
1623 incremental stream's source. For zvols, the destination device link is
1624 destroyed and recreated, which means the zvol cannot be accessed during
1625 the receive operation.
1626
1627 When a snapshot replication package stream that is generated by using
1628 the zfs send -R command is received, any snapshots that do not exist on
1629 the sending location are destroyed by using the zfs destroy -d command.
1630
1631 The name of the snapshot (and file system, if a full stream is
1632 received) that this subcommand creates depends on the argument type and
1633 the use of the -d or -e options.
1634
1635 If the argument is a snapshot name, the specified snapshot is created.
1636 If the argument is a file system or volume name, a snapshot with the
1637 same name as the sent snapshot is created within the specified
1638 filesystem or volume. If neither of the -d or -e options are
1639 specified, the provided target snapshot name is used exactly as
1640 provided.
1641
1642 The -d and -e options cause the file system name of the target snapshot
1643 to be determined by appending a portion of the sent snapshot's name to
1644 the specified target filesystem. If the -d option is specified, all
1645 but the first element of the sent snapshot's file system path (usually
1646 the pool name) is used and any required intermediate file systems
1647 within the specified one are created. If the -e option is specified,
1648 then only the last element of the sent snapshot's file system name
1649 (i.e. the name of the source file system itself) is used as the target
1650 file system name.
1651
1652 -F Force a rollback of the file system to the most recent snapshot
1653 before performing the receive operation. If receiving an
1654 incremental replication stream (for example, one generated by zfs
1655 send -R [-i|-I]), destroy snapshots and file systems that do not
1656 exist on the sending side.
1657
1658 -d Discard the first element of the sent snapshot's file system name,
1659 using the remaining elements to determine the name of the target
1660 file system for the new snapshot as described in the paragraph
1661 above.
1662
1663 -e Discard all but the last element of the sent snapshot's file system
1664 name, using that element to determine the name of the target file
1665 system for the new snapshot as described in the paragraph above.
1666
1667 -n Do not actually receive the stream. This can be useful in
1668 conjunction with the -v option to verify the name the receive
1669 operation would use.
1670
1671 -o origin=snapshot
1672 Forces the stream to be received as a clone of the given snapshot.
1673 This is only valid if the stream is an incremental stream whose
1674 source is the same as the provided origin.
1675
1676 -u File system that is associated with the received stream is not
1677 mounted.
1678
1679 -v Print verbose information about the stream and the time required to
1680 perform the receive operation.
1681
1682 -s If the receive is interrupted, save the partially received state,
1683 rather than deleting it. Interruption may be due to premature
1684 termination of the stream (e.g. due to network failure or failure
1685 of the remote system if the stream is being read over a network
1686 connection), a checksum error in the stream, termination of the zfs
1687 receive process, or unclean shutdown of the system.
1688
1689 The receive can be resumed with a stream generated by zfs send -t
1690 token, where the token is the value of the receive_resume_token
1691 property of the filesystem or volume which is received into.
1692
1693 To use this flag, the storage pool must have the extensible_dataset
1694 feature enabled. See zpool-features(5) for details on ZFS feature
1695 flags.
1696
1697 zfs receive -A filesystem|volume
1698 Abort an interrupted zfs receive -s, deleting its saved partially
1699 received state.
1700
1701 zfs allow filesystem|volume
1702 Displays permissions that have been delegated on the specified
1703 filesystem or volume. See the other forms of zfs allow for more
1704 information.
1705
1706 zfs allow [-dglu] user|group[,user|group]...
1707 perm|@setname[,perm|@setname]... filesystem|volume
1708 zfs allow [-dl] -e|everyone perm|@setname[,perm|@setname]...
1709 filesystem|volume
1710 Delegates ZFS administration permission for the file systems to non-
1711 privileged users.
1712
1713 -d Allow only for the descendent file systems.
1714
1715 -e|everyone
1716 Specifies that the permissions be delegated to everyone.
1717
1718 -g group[,group]...
1719 Explicitly specify that permissions are delegated to the group.
1720
1721 -l Allow "locally" only for the specified file system.
1722
1723 -u user[,user]...
1724 Explicitly specify that permissions are delegated to the user.
1725
1726 user|group[,user|group]...
1727 Specifies to whom the permissions are delegated. Multiple entities
1728 can be specified as a comma-separated list. If neither of the -gu
1729 options are specified, then the argument is interpreted
1730 preferentially as the keyword everyone, then as a user name, and
1731 lastly as a group name. To specify a user or group named
1732 "everyone", use the -g or -u options. To specify a group with the
1733 same name as a user, use the -g options.
1734
1735 perm|@setname[,perm|@setname]...
1736 The permissions to delegate. Multiple permissions may be specified
1737 as a comma-separated list. Permission names are the same as ZFS
1738 subcommand and property names. See the property list below.
1739 Property set names, which begin with @, may be specified. See the
1740 -s form below for details.
1741
1742 If neither of the -dl options are specified, or both are, then the
1743 permissions are allowed for the file system or volume, and all of its
1744 descendents.
1745
1746 Permissions are generally the ability to use a ZFS subcommand or change
1747 a ZFS property. The following permissions are available:
1748
1749 NAME TYPE NOTES
1750 allow subcommand Must also have the permission that is being
1751 allowed
1752 clone subcommand Must also have the 'create' ability and 'mount'
1753 ability in the origin file system
1754 create subcommand Must also have the 'mount' ability
1755 destroy subcommand Must also have the 'mount' ability
1756 diff subcommand Allows lookup of paths within a dataset
1757 given an object number, and the ability to
1758 create snapshots necessary to 'zfs diff'.
1759 mount subcommand Allows mount/umount of ZFS datasets
1760 promote subcommand Must also have the 'mount'
1761 and 'promote' ability in the origin file system
1762 receive subcommand Must also have the 'mount' and 'create' ability
1763 rename subcommand Must also have the 'mount' and 'create'
1764 ability in the new parent
1765 rollback subcommand Must also have the 'mount' ability
1766 send subcommand
1767 share subcommand Allows sharing file systems over NFS or SMB
1768 protocols
1769 snapshot subcommand Must also have the 'mount' ability
1770
1771 groupquota other Allows accessing any groupquota@... property
1772 groupused other Allows reading any groupused@... property
1773 userprop other Allows changing any user property
1774 userquota other Allows accessing any userquota@... property
1775 userused other Allows reading any userused@... property
1776
1777 aclinherit property
1778 aclmode property
1779 atime property
1780 canmount property
1781 casesensitivity property
1782 checksum property
1783 compression property
1784 copies property
1785 devices property
1786 exec property
1787 filesystem_limit property
1788 mountpoint property
1789 nbmand property
1790 normalization property
1791 primarycache property
1792 quota property
1793 readonly property
1794 recordsize property
1795 refquota property
1796 refreservation property
1797 reservation property
1798 secondarycache property
1799 setuid property
1800 sharenfs property
1801 sharesmb property
1802 snapdir property
1803 snapshot_limit property
1804 utf8only property
1805 version property
1806 volblocksize property
1807 volsize property
1808 vscan property
1809 xattr property
1810 zoned property
1811
1812 zfs allow -c perm|@setname[,perm|@setname]... filesystem|volume
1813 Sets "create time" permissions. These permissions are granted (locally)
1814 to the creator of any newly-created descendent file system.
1815
1816 zfs allow -s @setname perm|@setname[,perm|@setname]... filesystem|volume
1817 Defines or adds permissions to a permission set. The set can be used by
1818 other zfs allow commands for the specified file system and its
1819 descendents. Sets are evaluated dynamically, so changes to a set are
1820 immediately reflected. Permission sets follow the same naming
1821 restrictions as ZFS file systems, but the name must begin with @, and
1822 can be no more than 64 characters long.
1823
1824 zfs unallow [-dglru] user|group[,user|group]...
1825 [perm|@setname[,perm|@setname]...] filesystem|volume
1826 zfs unallow [-dlr] -e|everyone [perm|@setname[,perm|@setname]...]
1827 filesystem|volume
1828 zfs unallow [-r] -c [perm|@setname[,perm|@setname]...] filesystem|volume
1829 Removes permissions that were granted with the zfs allow command. No
1830 permissions are explicitly denied, so other permissions granted are
1831 still in effect. For example, if the permission is granted by an
1832 ancestor. If no permissions are specified, then all permissions for the
1833 specified user, group, or everyone are removed. Specifying everyone (or
1834 using the -e option) only removes the permissions that were granted to
1835 everyone, not all permissions for every user and group. See the zfs
1836 allow command for a description of the -ldugec options.
1837
1838 -r Recursively remove the permissions from this file system and all
1839 descendents.
1840
1841 zfs unallow [-r] -s -@setname [perm|@setname[,perm|@setname]...]
1842 filesystem|volume
1843 Removes permissions from a permission set. If no permissions are
1844 specified, then all permissions are removed, thus removing the set
1845 entirely.
1846
1847 zfs hold [-r] tag snapshot...
1848 Adds a single reference, named with the tag argument, to the specified
1849 snapshot or snapshots. Each snapshot has its own tag namespace, and
1850 tags must be unique within that space.
1851
1852 If a hold exists on a snapshot, attempts to destroy that snapshot by
1853 using the zfs destroy command return EBUSY.
1854
1855 -r Specifies that a hold with the given tag is applied recursively to
1856 the snapshots of all descendent file systems.
1857
1858 zfs holds [-r] snapshot...
1859 Lists all existing user references for the given snapshot or snapshots.
1860
1861 -r Lists the holds that are set on the named descendent snapshots, in
1862 addition to listing the holds on the named snapshot.
1863
1864 zfs release [-r] tag snapshot...
1865 Removes a single reference, named with the tag argument, from the
1866 specified snapshot or snapshots. The tag must already exist for each
1867 snapshot. If a hold exists on a snapshot, attempts to destroy that
1868 snapshot by using the zfs destroy command return EBUSY.
1869
1870 -r Recursively releases a hold with the given tag on the snapshots of
1871 all descendent file systems.
1872
1873 zfs diff [-FHt] snapshot snapshot|filesystem
1874 Display the difference between a snapshot of a given filesystem and
1875 another snapshot of that filesystem from a later time or the current
1876 contents of the filesystem. The first column is a character indicating
1877 the type of change, the other columns indicate pathname, new pathname
1878 (in case of rename), change in link count, and optionally file type
1879 and/or change time. The types of change are:
1880
1881 - The path has been removed
1882 + The path has been created
1883 M The path has been modified
1884 R The path has been renamed
1885
1886 -F Display an indication of the type of file, in a manner similar to
1887 the - option of ls(1).
1888
1889 B Block device
1890 C Character device
1891 / Directory
1892 > Door
1893 | Named pipe
1894 @ Symbolic link
1895 P Event port
1896 = Socket
1897 F Regular file
1898
1899 -H Give more parsable tab-separated output, without header lines and
1900 without arrows.
1901
1902 -t Display the path's inode change time as the first column of output.
1903
1904 EXIT STATUS
1905 The zfs utility exits 0 on success, 1 if an error occurs, and 2 if
1906 invalid command line options were specified.
1907
1908 EXAMPLES
1909 Example 1 Creating a ZFS File System Hierarchy
1910 The following commands create a file system named pool/home and a file
1911 system named pool/home/bob. The mount point /export/home is set for
1912 the parent file system, and is automatically inherited by the child
1913 file system.
1914
1915 # zfs create pool/home
1916 # zfs set mountpoint=/export/home pool/home
1917 # zfs create pool/home/bob
1918
1919 Example 2 Creating a ZFS Snapshot
1920 The following command creates a snapshot named yesterday. This
1921 snapshot is mounted on demand in the .zfs/snapshot directory at the
1922 root of the pool/home/bob file system.
1923
1924 # zfs snapshot pool/home/bob@yesterday
1925
1926 Example 3 Creating and Destroying Multiple Snapshots
1927 The following command creates snapshots named yesterday of pool/home
1928 and all of its descendent file systems. Each snapshot is mounted on
1929 demand in the .zfs/snapshot directory at the root of its file system.
1930 The second command destroys the newly created snapshots.
1931
1932 # zfs snapshot -r pool/home@yesterday
1933 # zfs destroy -r pool/home@yesterday
1934
1935 Example 4 Disabling and Enabling File System Compression
1936 The following command disables the compression property for all file
1937 systems under pool/home. The next command explicitly enables
1938 compression for pool/home/anne.
1939
1940 # zfs set compression=off pool/home
1941 # zfs set compression=on pool/home/anne
1942
1943 Example 5 Listing ZFS Datasets
1944 The following command lists all active file systems and volumes in the
1945 system. Snapshots are displayed if the listsnaps property is on. The
1946 default is off. See zpool(1M) for more information on pool properties.
1947
1948 # zfs list
1949 NAME USED AVAIL REFER MOUNTPOINT
1950 pool 450K 457G 18K /pool
1951 pool/home 315K 457G 21K /export/home
1952 pool/home/anne 18K 457G 18K /export/home/anne
1953 pool/home/bob 276K 457G 276K /export/home/bob
1954
1955 Example 6 Setting a Quota on a ZFS File System
1956 The following command sets a quota of 50 Gbytes for pool/home/bob.
1957
1958 # zfs set quota=50G pool/home/bob
1959
1960 Example 7 Listing ZFS Properties
1961 The following command lists all properties for pool/home/bob.
1962
1963 # zfs get all pool/home/bob
1964 NAME PROPERTY VALUE SOURCE
1965 pool/home/bob type filesystem -
1966 pool/home/bob creation Tue Jul 21 15:53 2009 -
1967 pool/home/bob used 21K -
1968 pool/home/bob available 20.0G -
1969 pool/home/bob referenced 21K -
1970 pool/home/bob compressratio 1.00x -
1971 pool/home/bob mounted yes -
1972 pool/home/bob quota 20G local
1973 pool/home/bob reservation none default
1974 pool/home/bob recordsize 128K default
1975 pool/home/bob mountpoint /pool/home/bob default
1976 pool/home/bob sharenfs off default
1977 pool/home/bob checksum on default
1978 pool/home/bob compression on local
1979 pool/home/bob atime on default
1980 pool/home/bob devices on default
1981 pool/home/bob exec on default
1982 pool/home/bob setuid on default
1983 pool/home/bob readonly off default
1984 pool/home/bob zoned off default
1985 pool/home/bob snapdir hidden default
1986 pool/home/bob aclmode discard default
1987 pool/home/bob aclinherit restricted default
1988 pool/home/bob canmount on default
1989 pool/home/bob xattr on default
1990 pool/home/bob copies 1 default
1991 pool/home/bob version 4 -
1992 pool/home/bob utf8only off -
1993 pool/home/bob normalization none -
1994 pool/home/bob casesensitivity sensitive -
1995 pool/home/bob vscan off default
1996 pool/home/bob nbmand off default
1997 pool/home/bob sharesmb off default
1998 pool/home/bob refquota none default
1999 pool/home/bob refreservation none default
2000 pool/home/bob primarycache all default
2001 pool/home/bob secondarycache all default
2002 pool/home/bob usedbysnapshots 0 -
2003 pool/home/bob usedbydataset 21K -
2004 pool/home/bob usedbychildren 0 -
2005 pool/home/bob usedbyrefreservation 0 -
2006
2007 The following command gets a single property value.
2008
2009 # zfs get -H -o value compression pool/home/bob
2010 on
2011 The following command lists all properties with local settings for
2012 pool/home/bob.
2013
2014 # zfs get -r -s local -o name,property,value all pool/home/bob
2015 NAME PROPERTY VALUE
2016 pool/home/bob quota 20G
2017 pool/home/bob compression on
2018
2019 Example 8 Rolling Back a ZFS File System
2020 The following command reverts the contents of pool/home/anne to the
2021 snapshot named yesterday, deleting all intermediate snapshots.
2022
2023 # zfs rollback -r pool/home/anne@yesterday
2024
2025 Example 9 Creating a ZFS Clone
2026 The following command creates a writable file system whose initial
2027 contents are the same as pool/home/bob@yesterday.
2028
2029 # zfs clone pool/home/bob@yesterday pool/clone
2030
2031 Example 10 Promoting a ZFS Clone
2032 The following commands illustrate how to test out changes to a file
2033 system, and then replace the original file system with the changed one,
2034 using clones, clone promotion, and renaming:
2035
2036 # zfs create pool/project/production
2037 populate /pool/project/production with data
2038 # zfs snapshot pool/project/production@today
2039 # zfs clone pool/project/production@today pool/project/beta
2040 make changes to /pool/project/beta and test them
2041 # zfs promote pool/project/beta
2042 # zfs rename pool/project/production pool/project/legacy
2043 # zfs rename pool/project/beta pool/project/production
2044 once the legacy version is no longer needed, it can be destroyed
2045 # zfs destroy pool/project/legacy
2046
2047 Example 11 Inheriting ZFS Properties
2048 The following command causes pool/home/bob and pool/home/anne to
2049 inherit the checksum property from their parent.
2050
2051 # zfs inherit checksum pool/home/bob pool/home/anne
2052
2053 Example 12 Remotely Replicating ZFS Data
2054 The following commands send a full stream and then an incremental
2055 stream to a remote machine, restoring them into poolB/received/fs@a and
2056 poolB/received/fs@b, respectively. poolB must contain the file system
2057 poolB/received, and must not initially contain poolB/received/fs.
2058
2059 # zfs send pool/fs@a | \
2060 ssh host zfs receive poolB/received/fs@a
2061 # zfs send -i a pool/fs@b | \
2062 ssh host zfs receive poolB/received/fs
2063
2064 Example 13 Using the zfs receive -d Option
2065 The following command sends a full stream of poolA/fsA/fsB@snap to a
2066 remote machine, receiving it into poolB/received/fsA/fsB@snap. The
2067 fsA/fsB@snap portion of the received snapshot's name is determined from
2068 the name of the sent snapshot. poolB must contain the file system
2069 poolB/received. If poolB/received/fsA does not exist, it is created as
2070 an empty file system.
2071
2072 # zfs send poolA/fsA/fsB@snap | \
2073 ssh host zfs receive -d poolB/received
2074
2075 Example 14 Setting User Properties
2076 The following example sets the user-defined com.example:department
2077 property for a dataset.
2078
2079 # zfs set com.example:department=12345 tank/accounting
2080
2081 Example 15 Performing a Rolling Snapshot
2082 The following example shows how to maintain a history of snapshots with
2083 a consistent naming scheme. To keep a week's worth of snapshots, the
2084 user destroys the oldest snapshot, renames the remaining snapshots, and
2085 then creates a new snapshot, as follows:
2086
2087 # zfs destroy -r pool/users@7daysago
2088 # zfs rename -r pool/users@6daysago @7daysago
2089 # zfs rename -r pool/users@5daysago @6daysago
2090 # zfs rename -r pool/users@yesterday @5daysago
2091 # zfs rename -r pool/users@yesterday @4daysago
2092 # zfs rename -r pool/users@yesterday @3daysago
2093 # zfs rename -r pool/users@yesterday @2daysago
2094 # zfs rename -r pool/users@today @yesterday
2095 # zfs snapshot -r pool/users@today
2096
2097 Example 16 Setting sharenfs Property Options on a ZFS File System
2098 The following commands show how to set sharenfs property options to
2099 enable rw access for a set of IP addresses and to enable root access
2100 for system neo on the tank/home file system.
2101
2102 # zfs set sharenfs='rw=@123.123.0.0/16,root=neo' tank/home
2103
2104 If you are using DNS for host name resolution, specify the fully
2105 qualified hostname.
2106
2107 Example 17 Delegating ZFS Administration Permissions on a ZFS Dataset
2108 The following example shows how to set permissions so that user cindys
2109 can create, destroy, mount, and take snapshots on tank/cindys. The
2110 permissions on tank/cindys are also displayed.
2111
2112 # zfs allow cindys create,destroy,mount,snapshot tank/cindys
2113 # zfs allow tank/cindys
2114 ---- Permissions on tank/cindys --------------------------------------
2115 Local+Descendent permissions:
2116 user cindys create,destroy,mount,snapshot
2117
2118 Because the tank/cindys mount point permission is set to 755 by
2119 default, user cindys will be unable to mount file systems under
2120 tank/cindys. Add an ACE similar to the following syntax to provide
2121 mount point access:
2122
2123 # chmod A+user:cindys:add_subdirectory:allow /tank/cindys
2124
2125 Example 18 Delegating Create Time Permissions on a ZFS Dataset
2126 The following example shows how to grant anyone in the group staff to
2127 create file systems in tank/users. This syntax also allows staff
2128 members to destroy their own file systems, but not destroy anyone
2129 else's file system. The permissions on tank/users are also displayed.
2130
2131 # zfs allow staff create,mount tank/users
2132 # zfs allow -c destroy tank/users
2133 # zfs allow tank/users
2134 ---- Permissions on tank/users ---------------------------------------
2135 Permission sets:
2136 destroy
2137 Local+Descendent permissions:
2138 group staff create,mount
2139
2140 Example 19 Defining and Granting a Permission Set on a ZFS Dataset
2141 The following example shows how to define and grant a permission set on
2142 the tank/users file system. The permissions on tank/users are also
2143 displayed.
2144
2145 # zfs allow -s @pset create,destroy,snapshot,mount tank/users
2146 # zfs allow staff @pset tank/users
2147 # zfs allow tank/users
2148 ---- Permissions on tank/users ---------------------------------------
2149 Permission sets:
2150 @pset create,destroy,mount,snapshot
2151 Local+Descendent permissions:
2152 group staff @pset
2153
2154 Example 20 Delegating Property Permissions on a ZFS Dataset
2155 The following example shows to grant the ability to set quotas and
2156 reservations on the users/home file system. The permissions on
2157 users/home are also displayed.
2158
2159 # zfs allow cindys quota,reservation users/home
2160 # zfs allow users/home
2161 ---- Permissions on users/home ---------------------------------------
2162 Local+Descendent permissions:
2163 user cindys quota,reservation
2164 cindys% zfs set quota=10G users/home/marks
2165 cindys% zfs get quota users/home/marks
2166 NAME PROPERTY VALUE SOURCE
2167 users/home/marks quota 10G local
2168
2169 Example 21 Removing ZFS Delegated Permissions on a ZFS Dataset
2170 The following example shows how to remove the snapshot permission from
2171 the staff group on the tank/users file system. The permissions on
2172 tank/users are also displayed.
2173
2174 # zfs unallow staff snapshot tank/users
2175 # zfs allow tank/users
2176 ---- Permissions on tank/users ---------------------------------------
2177 Permission sets:
2178 @pset create,destroy,mount,snapshot
2179 Local+Descendent permissions:
2180 group staff @pset
2181
2182 Example 22 Showing the differences between a snapshot and a ZFS Dataset
2183 The following example shows how to see what has changed between a prior
2184 snapshot of a ZFS dataset and its current state. The -F option is used
2185 to indicate type information for the files affected.
2186
2187 # zfs diff -F tank/test@before tank/test
2188 M / /tank/test/
2189 M F /tank/test/linked (+1)
2190 R F /tank/test/oldname -> /tank/test/newname
2191 - F /tank/test/deleted
2192 + F /tank/test/created
2193 M F /tank/test/modified
2194
2195 INTERFACE STABILITY
2196 Commited.
2197
2198 SEE ALSO
2199 gzip(1,) ssh(1), mount(1M), share(1M), sharemgr(1M), unshare(1M),
2200 zonecfg(1M), zpool(1M), chmod(2), stat(2), write(2), fsync(3C),
2201 dfstab(4), acl(5), attributes(5)
2202
2203 illumos June 8, 2015 illumos