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 [-DFLPRenpv] [[-I|-i] snapshot] snapshot
42 zfs send [-FLe] [-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 o POSIX name (for example, joe)
393
394 o POSIX numeric ID (for example, 789)
395
396 o SID name (for example, joe.smith@mydomain)
397
398 o 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
483 whose 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
488 when aclmode is set to restricted, you must first remove all ACEs which
489 do 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 mountpoint=path|none|legacy
596 Controls the mount point used for this file system. See the Mount
597 Points section for more information on how this property is used.
598
599 When the mountpoint property is changed for a file system, the file
600 system and any children that inherit the mount point are unmounted. If
601 the new value is legacy, then they remain unmounted. Otherwise, they
602 are automatically remounted in the new location if the property was
603 previously legacy or none, or if they were mounted before the property
604 was changed. In addition, any shared file systems are unshared and
605 shared in the new location.
606
607 nbmand=on|off
608 Controls whether the file system should be mounted with nbmand (Non
609 Blocking mandatory locks). This is used for SMB clients. Changes to
610 this property only take effect when the file system is umounted and
611 remounted. See mount(1M) for more information on nbmand mounts.
612
613 primarycache=all|none|metadata
614 Controls what is cached in the primary cache (ARC). If this property
615 is set to all, then both user data and metadata is cached. If this
616 property is set to none, then neither user data nor metadata is cached.
617 If this property is set to metadata, then only metadata is cached. The
618 default value is all.
619
620 quota=size|none
621 Limits the amount of space a dataset and its descendents can consume.
622 This property enforces a hard limit on the amount of space used. This
623 includes all space consumed by descendents, including file systems and
624 snapshots. Setting a quota on a descendent of a dataset that already
625 has a quota does not override the ancestor's quota, but rather imposes
626 an additional limit.
627
628 Quotas cannot be set on volumes, as the volsize property acts as an
629 implicit quota.
630
631 snapshot_limit=count|none
632 Limits the number of snapshots that can be created on a dataset and its
633 descendents. Setting a snapshot_limit on a descendent of a dataset that
634 already has a snapshot_limit does not override the ancestor's
635 snapshot_limit, but rather imposes an additional limit. The limit is
636 not enforced if the user is allowed to change the limit. For example,
637 this means that recursive snapshots taken from the global zone are
638 counted against each delegated dataset within a zone. This feature must
639 be enabled to be used (see zpool-features(5)).
640
641 userquota@user=size|none
642 Limits the amount of space consumed by the specified user. User space
643 consumption is identified by the userspace@user property.
644
645 Enforcement of user quotas may be delayed by several seconds. This
646 delay means that a user might exceed their quota before the system
647 notices that they are over quota and begins to refuse additional writes
648 with the EDQUOT error message. See the zfs userspace subcommand for
649 more information.
650
651 Unprivileged users can only access their own groups' space usage. The
652 root user, or a user who has been granted the userquota privilege with
653 zfs allow, can get and set everyone's quota.
654
655 This property is not available on volumes, on file systems before
656 version 4, or on pools before version 15. The userquota@... properties
657 are not displayed by zfs get all. The user's name must be appended
658 after the @ symbol, using one of the following forms:
659
660 o POSIX name (for example, joe)
661
662 o POSIX numeric ID (for example, 789)
663
664 o SID name (for example, joe.smith@mydomain)
665
666 o SID numeric ID (for example, S-1-123-456-789)
667
668 groupquota@group=size|none
669 Limits the amount of space consumed by the specified group. Group space
670 consumption is identified by the groupused@group property.
671
672 Unprivileged users can access only their own groups' space usage. The
673 root user, or a user who has been granted the groupquota privilege with
674 zfs allow, can get and set all groups' quotas.
675
676 readonly=on|off
677 Controls whether this dataset can be modified. The default value is
678 off.
679
680 This property can also be referred to by its shortened column name,
681 rdonly.
682
683 recordsize=size
684 Specifies a suggested block size for files in the file system. This
685 property is designed solely for use with database workloads that access
686 files in fixed-size records. ZFS automatically tunes block sizes
687 according to internal algorithms optimized for typical access patterns.
688
689 For databases that create very large files but access them in small
690 random chunks, these algorithms may be suboptimal. Specifying a
691 recordsize greater than or equal to the record size of the database can
692 result in significant performance gains. Use of this property for
693 general purpose file systems is strongly discouraged, and may adversely
694 affect performance.
695
696 The size specified must be a power of two greater than or equal to 512
697 and less than or equal to 128 Kbytes. If the large_blocks feature is
698 enabled on the pool, the size may be up to 1 Mbyte. See
699 zpool-features(5) for details on ZFS feature flags.
700
701 Changing the file system's recordsize affects only files created
702 afterward; existing files are unaffected.
703
704 This property can also be referred to by its shortened column name,
705 recsize.
706
707 redundant_metadata=all|most
708 Controls what types of metadata are stored redundantly. ZFS stores an
709 extra copy of metadata, so that if a single block is corrupted, the
710 amount of user data lost is limited. This extra copy is in addition to
711 any redundancy provided at the pool level (e.g. by mirroring or
712 RAID-Z), and is in addition to an extra copy specified by the copies
713 property (up to a total of 3 copies). For example if the pool is
714 mirrored, copies=2, and redundant_metadata=most, then ZFS stores 6
715 copies of most metadata, and 4 copies of data and some metadata.
716
717 When set to all, ZFS stores an extra copy of all metadata. If a single
718 on-disk block is corrupt, at worst a single block of user data (which
719 is recordsize bytes long) can be lost.
720
721 When set to most, ZFS stores an extra copy of most types of metadata.
722 This can improve performance of random writes, because less metadata
723 must be written. In practice, at worst about 100 blocks (of recordsize
724 bytes each) of user data can be lost if a single on-disk block is
725 corrupt. The exact behavior of which metadata blocks are stored
726 redundantly may change in future releases.
727
728 The default value is all.
729
730 refquota=size|none
731 Limits the amount of space a dataset can consume. This property
732 enforces a hard limit on the amount of space used. This hard limit does
733 not include space used by descendents, including file systems and
734 snapshots.
735
736 refreservation=size|none
737 The minimum amount of space guaranteed to a dataset, not including its
738 descendents. When the amount of space used is below this value, the
739 dataset is treated as if it were taking up the amount of space
740 specified by refreservation. The refreservation reservation is
741 accounted for in the parent datasets' space used, and counts against
742 the parent datasets' quotas and reservations.
743
744 If refreservation is set, a snapshot is only allowed if there is enough
745 free pool space outside of this reservation to accommodate the current
746 number of "referenced" bytes in the dataset.
747
748 This property can also be referred to by its shortened column name,
749 refreserv.
750
751 reservation=size|none
752 The minimum amount of space guaranteed to a dataset and its
753 descendents. When the amount of space used is below this value, the
754 dataset is treated as if it were taking up the amount of space
755 specified by its reservation. Reservations are accounted for in the
756 parent datasets' space used, and count against the parent datasets'
757 quotas and reservations.
758
759 This property can also be referred to by its shortened column name,
760 reserv.
761
762 secondarycache=all|none|metadata
763 Controls what is cached in the secondary cache (L2ARC). If this
764 property is set to all, then both user data and metadata is cached. If
765 this property is set to none, then neither user data nor metadata is
766 cached. If this property is set to metadata, then only metadata is
767 cached. The default value is all.
768
769 setuid=on|off
770 Controls whether the setuid bit is respected for the file system. The
771 default value is on.
772
773 sharesmb=on|off|opts
774 Controls whether the file system is shared via SMB, and what options
775 are to be used. A file system with the sharesmb property set to off is
776 managed through traditional tools such as sharemgr(1M). Otherwise, the
777 file system is automatically shared and unshared with the zfs share and
778 zfs unshare commands. If the property is set to on, the sharemgr(1M)
779 command is invoked with no options. Otherwise, the sharemgr(1M) command
780 is invoked with options equivalent to the contents of this property.
781
782 Because SMB shares requires a resource name, a unique resource name is
783 constructed from the dataset name. The constructed name is a copy of
784 the dataset name except that the characters in the dataset name, which
785 would be illegal in the resource name, are replaced with underscore (_)
786 characters. A pseudo property "name" is also supported that allows you
787 to replace the data set name with a specified name. The specified name
788 is then used to replace the prefix dataset in the case of inheritance.
789 For example, if the dataset data/home/john is set to name=john, then
790 data/home/john has a resource name of john. If a child dataset
791 data/home/john/backups is shared, it has a resource name of
792 john_backups.
793
794 When SMB shares are created, the SMB share name appears as an entry in
795 the .zfs/shares directory. You can use the ls or chmod command to
796 display the share-level ACLs on the entries in this directory.
797
798 When the sharesmb property is changed for a dataset, the dataset and
799 any children inheriting the property are re-shared with the new
800 options, only if the property was previously set to off, or if they
801 were shared before the property was changed. If the new property is set
802 to off, the file systems are unshared.
803
804 sharenfs=on|off|opts
805 Controls whether the file system is shared via NFS, and what options
806 are to be used. A file system with a sharenfs property of off is
807 managed through traditional tools such as share(1M), unshare(1M), and
808 dfstab(4). Otherwise, the file system is automatically shared and
809 unshared with the zfs share and zfs unshare commands. If the property
810 is set to on, share(1M) command is invoked with no options. Otherwise,
811 the share(1M) command is invoked with options equivalent to the
812 contents of this property.
813
814 When the sharenfs property is changed for a dataset, the dataset and
815 any children inheriting the property are re-shared with the new
816 options, only if the property was previously off, or if they were
817 shared before the property was changed. If the new property is off, the
818 file systems are unshared.
819
820 logbias=latency|throughput
821 Provide a hint to ZFS about handling of synchronous requests in this
822 dataset. If logbias is set to latency (the default), ZFS will use pool
823 log devices (if configured) to handle the requests at low latency. If
824 logbias is set to throughput, ZFS will not use configured pool log
825 devices. ZFS will instead optimize synchronous operations for global
826 pool throughput and efficient use of resources.
827
828 snapdir=hidden|visible
829 Controls whether the .zfs directory is hidden or visible in the root of
830 the file system as discussed in the Snapshots section. The default
831 value is hidden.
832
833 sync=standard|always|disabled
834 Controls the behavior of synchronous requests (e.g. fsync, O_DSYNC).
835 standard is the POSIX specified behavior of ensuring all synchronous
836 requests are written to stable storage and all devices are flushed to
837 ensure data is not cached by device controllers (this is the default).
838 always causes every file system transaction to be written and flushed
839 before its system call returns. This has a large performance penalty.
840 disabled disables synchronous requests. File system transactions are
841 only committed to stable storage periodically. This option will give
842 the highest performance. However, it is very dangerous as ZFS would be
843 ignoring the synchronous transaction demands of applications such as
844 databases or NFS. Administrators should only use this option when the
845 risks are understood.
846
847 version=N|current
848 The on-disk version of this file system, which is independent of the
849 pool version. This property can only be set to later supported
850 versions. See the zfs upgrade command.
851
852 volsize=size
853 For volumes, specifies the logical size of the volume. By default,
854 creating a volume establishes a reservation of equal size. For storage
855 pools with a version number of 9 or higher, a refreservation is set
856 instead. Any changes to volsize are reflected in an equivalent change
857 to the reservation (or refreservation). The volsize can only be set to
858 a multiple of volblocksize, and cannot be zero.
859
860 The reservation is kept equal to the volume's logical size to prevent
861 unexpected behavior for consumers. Without the reservation, the volume
862 could run out of space, resulting in undefined behavior or data
863 corruption, depending on how the volume is used. These effects can also
864 occur when the volume size is changed while it is in use (particularly
865 when shrinking the size). Extreme care should be used when adjusting
866 the volume size.
867
868 Though not recommended, a "sparse volume" (also known as "thin
869 provisioning") can be created by specifying the -s option to the zfs
870 create -V command, or by changing the reservation after the volume has
871 been created. A "sparse volume" is a volume where the reservation is
872 less then the volume size. Consequently, writes to a sparse volume can
873 fail with ENOSPC when the pool is low on space. For a sparse volume,
874 changes to volsize are not reflected in the reservation.
875
876 vscan=on|off
877 Controls whether regular files should be scanned for viruses when a
878 file is opened and closed. In addition to enabling this property, the
879 virus scan service must also be enabled for virus scanning to occur.
880 The default value is off.
881
882 xattr=on|off
883 Controls whether extended attributes are enabled for this file system.
884 The default value is on.
885
886 zoned=on|off
887 Controls whether the dataset is managed from a non-global zone. See the
888 Zones section for more information. The default value is off.
889
890 The following three properties cannot be changed after the file system is
891 created, and therefore, should be set when the file system is created. If
892 the properties are not set with the zfs create or zpool create commands,
893 these properties are inherited from the parent dataset. If the parent
894 dataset lacks these properties due to having been created prior to these
895 features being supported, the new file system will have the default
896 values for these properties.
897
898 casesensitivity=sensitive|insensitive|mixed
899 Indicates whether the file name matching algorithm used by the file
900 system should be case-sensitive, case-insensitive, or allow a
901 combination of both styles of matching. The default value for the
902 casesensitivity property is sensitive. Traditionally, UNIX and POSIX
903 file systems have case-sensitive file names.
904
905 The mixed value for the casesensitivity property indicates that the
906 file system can support requests for both case-sensitive and case-
907 insensitive matching behavior. Currently, case-insensitive matching
908 behavior on a file system that supports mixed behavior is limited to
909 the SMB server product. For more information about the mixed value
910 behavior, see the "ZFS Administration Guide".
911
912 normalization=none|formC|formD|formKC|formKD
913 Indicates whether the file system should perform a unicode
914 normalization of file names whenever two file names are compared, and
915 which normalization algorithm should be used. File names are always
916 stored unmodified, names are normalized as part of any comparison
917 process. If this property is set to a legal value other than none, and
918 the utf8only property was left unspecified, the utf8only property is
919 automatically set to on. The default value of the normalization
920 property is none. This property cannot be changed after the file
921 system is created.
922
923 utf8only=on|off
924 Indicates whether the file system should reject file names that include
925 characters that are not present in the UTF-8 character code set. If
926 this property is explicitly set to off, the normalization property must
927 either not be explicitly set or be set to none. The default value for
928 the utf8only property is off. This property cannot be changed after
929 the file system is created.
930
931 The casesensitivity, normalization, and utf8only properties are also new
932 permissions that can be assigned to non-privileged users by using the ZFS
933 delegated administration feature.
934
935 Temporary Mount Point Properties
936 When a file system is mounted, either through mount(1M) for legacy mounts
937 or the zfs mount command for normal file systems, its mount options are
938 set according to its properties. The correlation between properties and
939 mount options is as follows:
940
941 PROPERTY MOUNT OPTION
942 devices devices/nodevices
943 exec exec/noexec
944 readonly ro/rw
945 setuid setuid/nosetuid
946 xattr xattr/noxattr
947
948 In addition, these options can be set on a per-mount basis using the -o
949 option, without affecting the property that is stored on disk. The values
950 specified on the command line override the values stored in the dataset.
951 The nosuid option is an alias for nodevices,nosetuid. These properties
952 are reported as "temporary" by the zfs get command. If the properties are
953 changed while the dataset is mounted, the new setting overrides any
954 temporary settings.
955
956 User Properties
957 In addition to the standard native properties, ZFS supports arbitrary
958 user properties. User properties have no effect on ZFS behavior, but
959 applications or administrators can use them to annotate datasets (file
960 systems, volumes, and snapshots).
961
962 User property names must contain a colon (":") character to distinguish
963 them from native properties. They may contain lowercase letters, numbers,
964 and the following punctuation characters: colon (":"), dash ("-"), period
965 ("."), and underscore ("_"). The expected convention is that the
966 property name is divided into two portions such as module:property, but
967 this namespace is not enforced by ZFS. User property names can be at
968 most 256 characters, and cannot begin with a dash ("-").
969
970 When making programmatic use of user properties, it is strongly suggested
971 to use a reversed DNS domain name for the module component of property
972 names to reduce the chance that two independently-developed packages use
973 the same property name for different purposes.
974
975 The values of user properties are arbitrary strings, are always
976 inherited, and are never validated. All of the commands that operate on
977 properties (zfs list, zfs get, zfs set, and so forth) can be used to
978 manipulate both native properties and user properties. Use the zfs
979 inherit command to clear a user property . If the property is not defined
980 in any parent dataset, it is removed entirely. Property values are
981 limited to 1024 characters.
982
983 ZFS Volumes as Swap or Dump Devices
984 During an initial installation a swap device and dump device are created
985 on ZFS volumes in the ZFS root pool. By default, the swap area size is
986 based on 1/2 the size of physical memory up to 2 Gbytes. The size of the
987 dump device depends on the kernel's requirements at installation time.
988 Separate ZFS volumes must be used for the swap area and dump devices. Do
989 not swap to a file on a ZFS file system. A ZFS swap file configuration is
990 not supported.
991
992 If you need to change your swap area or dump device after the system is
993 installed or upgraded, use the swap(1M) and dumpadm(1M) commands.
994
995 SUBCOMMANDS
996 All subcommands that modify state are logged persistently to the pool in
997 their original form.
998
999 zfs -?
1000 Displays a help message.
1001
1002 zfs create [-p] [-o property=value]... filesystem
1003 Creates a new ZFS file system. The file system is automatically mounted
1004 according to the mountpoint property inherited from the parent.
1005
1006 -o property=value
1007 Sets the specified property as if the command zfs set
1008 property=value was invoked at the same time the dataset was
1009 created. Any editable ZFS property can also be set at creation
1010 time. Multiple -o options can be specified. An error results if the
1011 same property is specified in multiple -o options.
1012
1013 -p Creates all the non-existing parent datasets. Datasets created in
1014 this manner are automatically mounted according to the mountpoint
1015 property inherited from their parent. Any property specified on the
1016 command line using the -o option is ignored. If the target
1017 filesystem already exists, the operation completes successfully.
1018
1019 zfs create [-ps] [-b blocksize] [-o property=value]... -V size volume
1020 Creates a volume of the given size. The volume is exported as a block
1021 device in /dev/zvol/{dsk,rdsk}/path, where path is the name of the
1022 volume in the ZFS namespace. The size represents the logical size as
1023 exported by the device. By default, a reservation of equal size is
1024 created.
1025
1026 size is automatically rounded up to the nearest 128 Kbytes to ensure
1027 that the volume has an integral number of blocks regardless of
1028 blocksize.
1029
1030 -b blocksize
1031 Equivalent to -o volblocksize=blocksize. If this option is
1032 specified in conjunction with -o volblocksize, the resulting
1033 behavior is undefined.
1034
1035 -o property=value
1036 Sets the specified property as if the zfs set property=value
1037 command was invoked at the same time the dataset was created. Any
1038 editable ZFS property can also be set at creation time. Multiple -o
1039 options can be specified. An error results if the same property is
1040 specified in multiple -o options.
1041
1042 -p Creates all the non-existing parent datasets. Datasets created in
1043 this manner are automatically mounted according to the mountpoint
1044 property inherited from their parent. Any property specified on the
1045 command line using the -o option is ignored. If the target
1046 filesystem already exists, the operation completes successfully.
1047
1048 -s Creates a sparse volume with no reservation. See volsize in the
1049 Native Properties section for more information about sparse
1050 volumes.
1051
1052 zfs destroy [-Rfnprv] filesystem|volume
1053 Destroys the given dataset. By default, the command unshares any file
1054 systems that are currently shared, unmounts any file systems that are
1055 currently mounted, and refuses to destroy a dataset that has active
1056 dependents (children or clones).
1057
1058 -R Recursively destroy all dependents, including cloned file systems
1059 outside the target hierarchy.
1060
1061 -f Force an unmount of any file systems using the unmount -f command.
1062 This option has no effect on non-file systems or unmounted file
1063 systems.
1064
1065 -n Do a dry-run ("No-op") deletion. No data will be deleted. This is
1066 useful in conjunction with the -v or -p flags to determine what
1067 data would be deleted.
1068
1069 -p Print machine-parsable verbose information about the deleted data.
1070
1071 -r Recursively destroy all children.
1072
1073 -v Print verbose information about the deleted data.
1074
1075 Extreme care should be taken when applying either the -r or the -R
1076 options, as they can destroy large portions of a pool and cause
1077 unexpected behavior for mounted file systems in use.
1078
1079 zfs destroy [-Rdnprv] filesystem|volume@snap[%snap[,snap[%snap]]]...
1080 The given snapshots are destroyed immediately if and only if the zfs
1081 destroy command without the -d option would have destroyed it. Such
1082 immediate destruction would occur, for example, if the snapshot had no
1083 clones and the user-initiated reference count were zero.
1084
1085 If a snapshot does not qualify for immediate destruction, it is marked
1086 for deferred deletion. In this state, it exists as a usable, visible
1087 snapshot until both of the preconditions listed above are met, at which
1088 point it is destroyed.
1089
1090 An inclusive range of snapshots may be specified by separating the
1091 first and last snapshots with a percent sign. The first and/or last
1092 snapshots may be left blank, in which case the filesystem's oldest or
1093 newest snapshot will be implied.
1094
1095 Multiple snapshots (or ranges of snapshots) of the same filesystem or
1096 volume may be specified in a comma-separated list of snapshots. Only
1097 the snapshot's short name (the part after the @) should be specified
1098 when using a range or comma-separated list to identify multiple
1099 snapshots.
1100
1101 -R Recursively destroy all clones of these snapshots, including the
1102 clones, snapshots, and children. If this flag is specified, the -d
1103 flag will have no effect.
1104
1105 -d Defer snapshot deletion.
1106
1107 -n Do a dry-run ("No-op") deletion. No data will be deleted. This is
1108 useful in conjunction with the -p or -v flags to determine what
1109 data would be deleted.
1110
1111 -p Print machine-parsable verbose information about the deleted data.
1112
1113 -r Destroy (or mark for deferred deletion) all snapshots with this
1114 name in descendent file systems.
1115
1116 -v Print verbose information about the deleted data.
1117
1118 Extreme care should be taken when applying either the -r or the -R
1119 options, as they can destroy large portions of a pool and cause
1120 unexpected behavior for mounted file systems in use.
1121
1122 zfs destroy filesystem|volume#bookmark
1123 The given bookmark is destroyed.
1124
1125 zfs snapshot [-r] [-o property=value]...
1126 filesystem@snapname|volume@snapname...
1127 Creates snapshots with the given names. All previous modifications by
1128 successful system calls to the file system are part of the snapshots.
1129 Snapshots are taken atomically, so that all snapshots correspond to the
1130 same moment in time. See the Snapshots section for details.
1131
1132 -o property=value
1133 Sets the specified property; see zfs create for details.
1134
1135 -r Recursively create snapshots of all descendent datasets
1136
1137 zfs rollback [-Rfr] snapshot
1138 Roll back the given dataset to a previous snapshot. When a dataset is
1139 rolled back, all data that has changed since the snapshot is discarded,
1140 and the dataset reverts to the state at the time of the snapshot. By
1141 default, the command refuses to roll back to a snapshot other than the
1142 most recent one. In order to do so, all intermediate snapshots and
1143 bookmarks must be destroyed by specifying the -r option.
1144
1145 The -rR options do not recursively destroy the child snapshots of a
1146 recursive snapshot. Only direct snapshots of the specified filesystem
1147 are destroyed by either of these options. To completely roll back a
1148 recursive snapshot, you must rollback the individual child snapshots.
1149
1150 -R Destroy any more recent snapshots and bookmarks, as well as any
1151 clones of those snapshots.
1152
1153 -f Used with the -R option to force an unmount of any clone file
1154 systems that are to be destroyed.
1155
1156 -r Destroy any snapshots and bookmarks more recent than the one
1157 specified.
1158
1159 zfs clone [-p] [-o property=value]... snapshot filesystem|volume
1160 Creates a clone of the given snapshot. See the Clones section for
1161 details. The target dataset can be located anywhere in the ZFS
1162 hierarchy, and is created as the same type as the original.
1163
1164 -o property=value
1165 Sets the specified property; see zfs create for details.
1166
1167 -p Creates all the non-existing parent datasets. Datasets created in
1168 this manner are automatically mounted according to the mountpoint
1169 property inherited from their parent. If the target filesystem or
1170 volume already exists, the operation completes successfully.
1171
1172 zfs promote clone-filesystem
1173 Promotes a clone file system to no longer be dependent on its "origin"
1174 snapshot. This makes it possible to destroy the file system that the
1175 clone was created from. The clone parent-child dependency relationship
1176 is reversed, so that the origin file system becomes a clone of the
1177 specified file system.
1178
1179 The snapshot that was cloned, and any snapshots previous to this
1180 snapshot, are now owned by the promoted clone. The space they use moves
1181 from the origin file system to the promoted clone, so enough space must
1182 be available to accommodate these snapshots. No new space is consumed
1183 by this operation, but the space accounting is adjusted. The promoted
1184 clone must not have any conflicting snapshot names of its own. The
1185 rename subcommand can be used to rename any conflicting snapshots.
1186
1187 zfs rename [-f] filesystem|volume|snapshot filesystem|volume|snapshot
1188 zfs rename [-fp] filesystem|volume filesystem|volume
1189 Renames the given dataset. The new target can be located anywhere in
1190 the ZFS hierarchy, with the exception of snapshots. Snapshots can only
1191 be renamed within the parent file system or volume. When renaming a
1192 snapshot, the parent file system of the snapshot does not need to be
1193 specified as part of the second argument. Renamed file systems can
1194 inherit new mount points, in which case they are unmounted and
1195 remounted at the new mount point.
1196
1197 -f Force unmount any filesystems that need to be unmounted in the
1198 process.
1199
1200 -p Creates all the nonexistent parent datasets. Datasets created in
1201 this manner are automatically mounted according to the mountpoint
1202 property inherited from their parent.
1203
1204 zfs rename -r snapshot snapshot
1205 Recursively rename the snapshots of all descendent datasets. Snapshots
1206 are the only dataset that can be renamed recursively.
1207
1208 zfs list [-r|-d depth] [-Hp] [-o property[,property]...] [-s property]...
1209 [-S property]... [-t type[,type]...] [filesystem|volume|snapshot]...
1210 Lists the property information for the given datasets in tabular form.
1211 If specified, you can list property information by the absolute
1212 pathname or the relative pathname. By default, all file systems and
1213 volumes are displayed. Snapshots are displayed if the listsnaps
1214 property is on (the default is off). The following fields are
1215 displayed, name,used,available,referenced,mountpoint.
1216
1217 -H Used for scripting mode. Do not print headers and separate fields
1218 by a single tab instead of arbitrary white space.
1219
1220 -S property
1221 Same as the -s option, but sorts by property in descending order.
1222
1223 -d depth
1224 Recursively display any children of the dataset, limiting the
1225 recursion to
1226
1227 -o property
1228 A comma-separated list of properties to display. The property must
1229 be:
1230
1231 o One of the properties described in the Native Properties
1232 section
1233
1234 o A user property
1235
1236 o The value name to display the dataset name
1237
1238 o The value space to display space usage properties on file
1239 systems and volumes. This is a shortcut for specifying -o
1240 name,avail,used,usedsnap,usedds,usedrefreserv,usedchild -t
1241 filesystem,volume syntax.
1242
1243 -p Display numbers in parsable (exact) values.
1244
1245 -r Recursively display any children of the dataset on the command
1246 line. depth. A depth of 1 will display only the dataset and its
1247 direct children.
1248
1249 -s property
1250 A property for sorting the output by column in ascending order
1251 based on the value of the property. The property must be one of the
1252 properties described in the Properties section, or the special
1253 value name to sort by the dataset name. Multiple properties can be
1254 specified at one time using multiple -s property options. Multiple
1255 -s options are evaluated from left to right in decreasing order of
1256 importance. The following is a list of sorting criteria:
1257
1258 o Numeric types sort in numeric order.
1259
1260 o String types sort in alphabetical order.
1261
1262 o Types inappropriate for a row sort that row to the literal
1263 bottom, regardless of the specified ordering.
1264
1265 If no sorting options are specified the existing behavior of zfs
1266 list is preserved.
1267
1268 -t type
1269 A comma-separated list of types to display, where type is one of
1270 filesystem, snapshot, volume, bookmark, or all. For example,
1271 specifying -t snapshot displays only snapshots.
1272
1273 zfs set property=value [property=value]... filesystem|volume|snapshot...
1274 Sets the property or list of properties to the given value(s) for each
1275 dataset. Only some properties can be edited. See the Properties
1276 section for more information on what properties can be set and
1277 acceptable values. Numeric values can be specified as exact values, or
1278 in a human-readable form with a suffix of B, K, M, G, T, P, E, Z (for
1279 bytes, kilobytes, megabytes, gigabytes, terabytes, petabytes, exabytes,
1280 or zettabytes, respectively). User properties can be set on snapshots.
1281 For more information, see the User Properties section.
1282
1283 zfs get [-r|-d depth] [-Hp] [-o field[,field]...] [-s source[,source]...]
1284 [-t type[,type]...] all | property[,property]...
1285 filesystem|volume|snapshot...
1286 Displays properties for the given datasets. If no datasets are
1287 specified, then the command displays properties for all datasets on the
1288 system. For each property, the following columns are displayed:
1289
1290 name Dataset name
1291 property Property name
1292 value Property value
1293 source Property source. Can either be local, default,
1294 temporary, inherited, or none (-).
1295
1296 All columns are displayed by default, though this can be controlled by
1297 using the -o option. This command takes a comma-separated list of
1298 properties as described in the Native Properties and User Properties
1299 sections.
1300
1301 The special value all can be used to display all properties that apply
1302 to the given dataset's type (filesystem, volume, snapshot, or
1303 bookmark).
1304
1305 -H Display output in a form more easily parsed by scripts. Any headers
1306 are omitted, and fields are explicitly separated by a single tab
1307 instead of an arbitrary amount of space.
1308
1309 -d depth
1310 Recursively display any children of the dataset, limiting the
1311 recursion to depth. A depth of 1 will display only the dataset and
1312 its direct children.
1313
1314 -o field
1315 A comma-separated list of columns to display.
1316 name,property,value,source is the default value.
1317
1318 -p Display numbers in parsable (exact) values.
1319
1320 -r Recursively display properties for any children.
1321
1322 -s source
1323 A comma-separated list of sources to display. Those properties
1324 coming from a source other than those in this list are ignored.
1325 Each source must be one of the following: local, default,
1326 inherited, temporary, and none. The default value is all sources.
1327
1328 -t type
1329 A comma-separated list of types to display, where type is one of
1330 filesystem, snapshot, volume, bookmark, or all.
1331
1332 zfs inherit [-rS] property filesystem|volume|snapshot...
1333 Clears the specified property, causing it to be inherited from an
1334 ancestor, restored to default if no ancestor has the property set, or
1335 with the -S option reverted to the received value if one exists. See
1336 the Properties section for a listing of default values, and details on
1337 which properties can be inherited.
1338
1339 -r Recursively inherit the given property for all children.
1340
1341 -S Revert the property to the received value if one exists; otherwise
1342 operate as if the -S option was not specified.
1343
1344 zfs upgrade
1345 Displays a list of file systems that are not the most recent version.
1346
1347 zfs upgrade -v
1348 Displays a list of currently supported file system versions.
1349
1350 zfs upgrade [-r] [-V version] -a | filesystem
1351 Upgrades file systems to a new on-disk version. Once this is done, the
1352 file systems will no longer be accessible on systems running older
1353 versions of the software. zfs send streams generated from new
1354 snapshots of these file systems cannot be accessed on systems running
1355 older versions of the software.
1356
1357 In general, the file system version is independent of the pool version.
1358 See zpool(1M) for information on the zpool upgrade command.
1359
1360 In some cases, the file system version and the pool version are
1361 interrelated and the pool version must be upgraded before the file
1362 system version can be upgraded.
1363
1364 -V version
1365 Upgrade to the specified version. If the -V flag is not specified,
1366 this command upgrades to the most recent version. This option can
1367 only be used to increase the version number, and only up to the
1368 most recent version supported by this software.
1369
1370 -a Upgrade all file systems on all imported pools.
1371
1372 filesystem
1373 Upgrade the specified file system.
1374
1375 -r Upgrade the specified file system and all descendent file systems.
1376
1377 zfs userspace [-Hinp] [-o field[,field]...] [-s field]... [-S field]...
1378 [-t type[,type]...] filesystem|snapshot
1379 Displays space consumed by, and quotas on, each user in the specified
1380 filesystem or snapshot. This corresponds to the userused@user and
1381 userquota@user properties.
1382
1383 -H Do not print headers, use tab-delimited output.
1384
1385 -S field
1386 Sort by this field in reverse order. See -s.
1387
1388 -i Translate SID to POSIX ID. The POSIX ID may be ephemeral if no
1389 mapping exists. Normal POSIX interfaces (for example, stat(2), ls
1390 -l) perform this translation, so the -i option allows the output
1391 from zfs userspace to be compared directly with those utilities.
1392 However, -i may lead to confusion if some files were created by an
1393 SMB user before a SMB-to-POSIX name mapping was established. In
1394 such a case, some files will be owned by the SMB entity and some by
1395 the POSIX entity. However, the -i option will report that the POSIX
1396 entity has the total usage and quota for both.
1397
1398 -n Print numeric ID instead of user/group name.
1399
1400 -o field[,field]...
1401 Display only the specified fields from the following set: type,
1402 name, used, quota. The default is to display all fields.
1403
1404 -p Use exact (parsable) numeric output.
1405
1406 -s field
1407 Sort output by this field. The -s and -S flags may be specified
1408 multiple times to sort first by one field, then by another. The
1409 default is -s type -s name.
1410
1411 -t type[,type]...
1412 Print only the specified types from the following set: all,
1413 posixuser, smbuser, posixgroup, smbgroup. The default is -t
1414 posixuser,smbuser. The default can be changed to include group
1415 types.
1416
1417 zfs groupspace [-Hinp] [-o field[,field]...] [-s field]... [-S field]...
1418 [-t type[,type]...] filesystem|snapshot
1419 Displays space consumed by, and quotas on, each group in the specified
1420 filesystem or snapshot. This subcommand is identical to zfs userspace,
1421 except that the default types to display are -t posixgroup,smbgroup.
1422
1423 zfs mount
1424 Displays all ZFS file systems currently mounted.
1425
1426 zfs mount [-Ov] [-o options] -a | filesystem
1427 Mounts ZFS file systems.
1428
1429 -O Perform an overlay mount. See mount(1M) for more information.
1430
1431 -a Mount all available ZFS file systems. Invoked automatically as part
1432 of the boot process.
1433
1434 filesystem
1435 Mount the specified filesystem.
1436
1437 -o options
1438 An optional, comma-separated list of mount options to use
1439 temporarily for the duration of the mount. See the Temporary Mount
1440 Point Properties section for details.
1441
1442 -v Report mount progress.
1443
1444 zfs unmount [-f] -a | filesystem|mountpoint
1445 Unmounts currently mounted ZFS file systems.
1446
1447 -a Unmount all available ZFS file systems. Invoked automatically as
1448 part of the shutdown process.
1449
1450 filesystem|mountpoint
1451 Unmount the specified filesystem. The command can also be given a
1452 path to a ZFS file system mount point on the system.
1453
1454 -f Forcefully unmount the file system, even if it is currently in use.
1455
1456 zfs share -a | filesystem
1457 Shares available ZFS file systems.
1458
1459 -a Share all available ZFS file systems. Invoked automatically as part
1460 of the boot process.
1461
1462 filesystem
1463 Share the specified filesystem according to the sharenfs and
1464 sharesmb properties. File systems are shared when the sharenfs or
1465 sharesmb property is set.
1466
1467 zfs unshare -a | filesystem|mountpoint
1468 Unshares currently shared ZFS file systems.
1469
1470 -a Unshare all available ZFS file systems. Invoked automatically as
1471 part of the shutdown process.
1472
1473 filesystem|mountpoint
1474 Unshare the specified filesystem. The command can also be given a
1475 path to a ZFS file system shared on the system.
1476
1477 zfs bookmark snapshot bookmark
1478 Creates a bookmark of the given snapshot. Bookmarks mark the point in
1479 time when the snapshot was created, and can be used as the incremental
1480 source for a zfs send command.
1481
1482 This feature must be enabled to be used. See zpool-features(5) for
1483 details on ZFS feature flags and the bookmarks feature.
1484
1485 zfs send [-DFLPRenpv] [[-I|-i] snapshot] snapshot
1486 Creates a stream representation of the second snapshot, which is
1487 written to standard output. The output can be redirected to a file or
1488 to a different system (for example, using ssh(1)). By default, a full
1489 stream is generated.
1490
1491 -D Generate a deduplicated stream. Blocks which would have been sent
1492 multiple times in the send stream will only be sent once. The
1493 receiving system must also support this feature to recieve a
1494 deduplicated stream. This flag can be used regardless of the
1495 dataset's dedup property, but performance will be much better if
1496 the filesystem uses a dedup-capable checksum (for example, sha256).
1497
1498 -I snapshot
1499 Generate a stream package that sends all intermediary snapshots
1500 from the first snapshot to the second snapshot. For example, -I @a
1501 fs@d is similar to -i @a fs@b; -i @b fs@c; -i @c fs@d. The
1502 incremental source may be specified as with the -i option.
1503
1504 -L Generate a stream which may contain blocks larger than 128KB. This
1505 flag has no effect if the large_blocks pool feature is disabled, or
1506 if the recordsize property of this filesystem has never been set
1507 above 128KB. The receiving system must have the large_blocks pool
1508 feature enabled as well. See zpool-features(5) for details on ZFS
1509 feature flags and the large_blocks feature.
1510
1511 -P Print machine-parsable verbose information about the stream package
1512 generated.
1513
1514 -R Generate a replication stream package, which will replicate the
1515 specified file system, and all descendent file systems, up to the
1516 named snapshot. When received, all properties, snapshots,
1517 descendent file systems, and clones are preserved.
1518
1519 If the -i or -I flags are used in conjunction with the -R flag, an
1520 incremental replication stream is generated. The current values of
1521 properties, and current snapshot and file system names are set when
1522 the stream is received. If the -F flag is specified when this
1523 stream is received, snapshots and file systems that do not exist on
1524 the sending side are destroyed.
1525
1526 -e Generate a more compact stream by using WRITE_EMBEDDED records for
1527 blocks which are stored more compactly on disk by the embedded_data
1528 pool feature. This flag has no effect if the embedded_data feature
1529 is disabled. The receiving system must have the embedded_data
1530 feature enabled. If the lz4_compress feature is active on the
1531 sending system, then the receiving system must have that feature
1532 enabled as well. See zpool-features(5) for details on ZFS feature
1533 flags and the embedded_data feature.
1534
1535 -F Generate a stream which omits free records. The stream will be
1536 more compact but the receiving system will not be able to receive
1537 the stream as a clone.
1538
1539 -i snapshot
1540 Generate an incremental stream from the first snapshot (the
1541 incremental source) to the second snapshot (the incremental
1542 target). The incremental source can be specified as the last
1543 component of the snapshot name (the @ character and following) and
1544 it is assumed to be from the same file system as the incremental
1545 target.
1546
1547 If the destination is a clone, the source may be the origin
1548 snapshot, which must be fully specified (for example,
1549 pool/fs@origin, not just @origin).
1550
1551 -n Do a dry-run ("No-op") send. Do not generate any actual send data.
1552 This is useful in conjunction with the -v or -P flags to determine
1553 what data will be sent. In this case, the verbose output will be
1554 written to standard output (contrast with a non-dry-run, where the
1555 stream is written to standard output and the verbose output goes to
1556 standard error).
1557
1558 -p Include the dataset's properties in the stream. This flag is
1559 implicit when -R is specified. The receiving system must also
1560 support this feature.
1561
1562 -v Print verbose information about the stream package generated. This
1563 information includes a per-second report of how much data has been
1564 sent.
1565
1566 The format of the stream is committed. You will be able to receive
1567 your streams on future versions of ZFS .
1568
1569 zfs send [-FLe] [-i snapshot|bookmark] filesystem|volume|snapshot
1570 Generate a send stream, which may be of a filesystem, and may be
1571 incremental from a bookmark. If the destination is a filesystem or
1572 volume, the pool must be read-only, or the filesystem must not be
1573 mounted. When the stream generated from a filesystem or volume is
1574 received, the default snapshot name will be "--head--".
1575
1576 -L Generate a stream which may contain blocks larger than 128KB. This
1577 flag has no effect if the large_blocks pool feature is disabled, or
1578 if the recordsize property of this filesystem has never been set
1579 above 128KB. The receiving system must have the large_blocks pool
1580 feature enabled as well. See zpool-features(5) for details on ZFS
1581 feature flags and the large_blocks feature.
1582
1583 -e Generate a more compact stream by using WRITE_EMBEDDED records for
1584 blocks which are stored more compactly on disk by the embedded_data
1585 pool feature. This flag has no effect if the embedded_data feature
1586 is disabled. The receiving system must have the embedded_data
1587 feature enabled. If the lz4_compress feature is active on the
1588 sending system, then the receiving system must have that feature
1589 enabled as well. See zpool-features(5) for details on ZFS feature
1590 flags and the embedded_data feature.
1591
1592 -F Generate a stream which omits free records. The stream will be
1593 more compact but the receiving system will not be able to receive
1594 the stream as a clone.
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 If the stream is a full send stream, this will create the
1674 filesystem described by the stream as a clone of the specified
1675 snapshot. Which snapshot was specified will not affect the success
1676 or failure of the receive, as long as the snapshot does exist. If
1677 the stream is an incremental send stream, all the normal
1678 verification will be performed.
1679
1680 -u File system that is associated with the received stream is not
1681 mounted.
1682
1683 -v Print verbose information about the stream and the time required to
1684 perform the receive operation.
1685
1686 -s If the receive is interrupted, save the partially received state,
1687 rather than deleting it. Interruption may be due to premature
1688 termination of the stream (e.g. due to network failure or failure
1689 of the remote system if the stream is being read over a network
1690 connection), a checksum error in the stream, termination of the zfs
1691 receive process, or unclean shutdown of the system.
1692
1693 The receive can be resumed with a stream generated by zfs send -t
1694 token, where the token is the value of the receive_resume_token
1695 property of the filesystem or volume which is received into.
1696
1697 To use this flag, the storage pool must have the extensible_dataset
1698 feature enabled. See zpool-features(5) for details on ZFS feature
1699 flags.
1700
1701 zfs receive -A filesystem|volume
1702 Abort an interrupted zfs receive -s, deleting its saved partially
1703 received state.
1704
1705 zfs allow filesystem|volume
1706 Displays permissions that have been delegated on the specified
1707 filesystem or volume. See the other forms of zfs allow for more
1708 information.
1709
1710 zfs allow [-dglu] user|group[,user|group]...
1711 perm|@setname[,perm|@setname]... filesystem|volume
1712 zfs allow [-dl] -e|everyone perm|@setname[,perm|@setname]...
1713 filesystem|volume
1714 Delegates ZFS administration permission for the file systems to non-
1715 privileged users.
1716
1717 -d Allow only for the descendent file systems.
1718
1719 -e|everyone
1720 Specifies that the permissions be delegated to everyone.
1721
1722 -g group[,group]...
1723 Explicitly specify that permissions are delegated to the group.
1724
1725 -l Allow "locally" only for the specified file system.
1726
1727 -u user[,user]...
1728 Explicitly specify that permissions are delegated to the user.
1729
1730 user|group[,user|group]...
1731 Specifies to whom the permissions are delegated. Multiple entities
1732 can be specified as a comma-separated list. If neither of the -gu
1733 options are specified, then the argument is interpreted
1734 preferentially as the keyword everyone, then as a user name, and
1735 lastly as a group name. To specify a user or group named
1736 "everyone", use the -g or -u options. To specify a group with the
1737 same name as a user, use the -g options.
1738
1739 perm|@setname[,perm|@setname]...
1740 The permissions to delegate. Multiple permissions may be specified
1741 as a comma-separated list. Permission names are the same as ZFS
1742 subcommand and property names. See the property list below.
1743 Property set names, which begin with @, may be specified. See the
1744 -s form below for details.
1745
1746 If neither of the -dl options are specified, or both are, then the
1747 permissions are allowed for the file system or volume, and all of its
1748 descendents.
1749
1750 Permissions are generally the ability to use a ZFS subcommand or change
1751 a ZFS property. The following permissions are available:
1752
1753 NAME TYPE NOTES
1754 allow subcommand Must also have the permission that is being
1755 allowed
1756 clone subcommand Must also have the 'create' ability and 'mount'
1757 ability in the origin file system
1758 create subcommand Must also have the 'mount' ability
1759 destroy subcommand Must also have the 'mount' ability
1760 diff subcommand Allows lookup of paths within a dataset
1761 given an object number, and the ability to
1762 create snapshots necessary to 'zfs diff'.
1763 mount subcommand Allows mount/umount of ZFS datasets
1764 promote subcommand Must also have the 'mount'
1765 and 'promote' ability in the origin file system
1766 receive subcommand Must also have the 'mount' and 'create' ability
1767 rename subcommand Must also have the 'mount' and 'create'
1768 ability in the new parent
1769 rollback subcommand Must also have the 'mount' ability
1770 send subcommand
1771 share subcommand Allows sharing file systems over NFS or SMB
1772 protocols
1773 snapshot subcommand Must also have the 'mount' ability
1774
1775 groupquota other Allows accessing any groupquota@... property
1776 groupused other Allows reading any groupused@... property
1777 userprop other Allows changing any user property
1778 userquota other Allows accessing any userquota@... property
1779 userused other Allows reading any userused@... property
1780
1781 aclinherit property
1782 aclmode property
1783 atime property
1784 canmount property
1785 casesensitivity property
1786 checksum property
1787 compression property
1788 copies property
1789 devices property
1790 exec property
1791 filesystem_limit property
1792 mountpoint property
1793 nbmand property
1794 normalization property
1795 primarycache property
1796 quota property
1797 readonly property
1798 recordsize property
1799 refquota property
1800 refreservation property
1801 reservation property
1802 secondarycache property
1803 setuid property
1804 sharenfs property
1805 sharesmb property
1806 snapdir property
1807 snapshot_limit property
1808 utf8only property
1809 version property
1810 volblocksize property
1811 volsize property
1812 vscan property
1813 xattr property
1814 zoned property
1815
1816 zfs allow -c perm|@setname[,perm|@setname]... filesystem|volume
1817 Sets "create time" permissions. These permissions are granted (locally)
1818 to the creator of any newly-created descendent file system.
1819
1820 zfs allow -s @setname perm|@setname[,perm|@setname]... filesystem|volume
1821 Defines or adds permissions to a permission set. The set can be used by
1822 other zfs allow commands for the specified file system and its
1823 descendents. Sets are evaluated dynamically, so changes to a set are
1824 immediately reflected. Permission sets follow the same naming
1825 restrictions as ZFS file systems, but the name must begin with @, and
1826 can be no more than 64 characters long.
1827
1828 zfs unallow [-dglru] user|group[,user|group]...
1829 [perm|@setname[,perm|@setname]...] filesystem|volume
1830 zfs unallow [-dlr] -e|everyone [perm|@setname[,perm|@setname]...]
1831 filesystem|volume
1832 zfs unallow [-r] -c [perm|@setname[,perm|@setname]...] filesystem|volume
1833 Removes permissions that were granted with the zfs allow command. No
1834 permissions are explicitly denied, so other permissions granted are
1835 still in effect. For example, if the permission is granted by an
1836 ancestor. If no permissions are specified, then all permissions for the
1837 specified user, group, or everyone are removed. Specifying everyone (or
1838 using the -e option) only removes the permissions that were granted to
1839 everyone, not all permissions for every user and group. See the zfs
1840 allow command for a description of the -ldugec options.
1841
1842 -r Recursively remove the permissions from this file system and all
1843 descendents.
1844
1845 zfs unallow [-r] -s -@setname [perm|@setname[,perm|@setname]...]
1846 filesystem|volume
1847 Removes permissions from a permission set. If no permissions are
1848 specified, then all permissions are removed, thus removing the set
1849 entirely.
1850
1851 zfs hold [-r] tag snapshot...
1852 Adds a single reference, named with the tag argument, to the specified
1853 snapshot or snapshots. Each snapshot has its own tag namespace, and
1854 tags must be unique within that space.
1855
1856 If a hold exists on a snapshot, attempts to destroy that snapshot by
1857 using the zfs destroy command return EBUSY.
1858
1859 -r Specifies that a hold with the given tag is applied recursively to
1860 the snapshots of all descendent file systems.
1861
1862 zfs holds [-r] snapshot...
1863 Lists all existing user references for the given snapshot or snapshots.
1864
1865 -r Lists the holds that are set on the named descendent snapshots, in
1866 addition to listing the holds on the named snapshot.
1867
1868 zfs release [-r] tag snapshot...
1869 Removes a single reference, named with the tag argument, from the
1870 specified snapshot or snapshots. The tag must already exist for each
1871 snapshot. If a hold exists on a snapshot, attempts to destroy that
1872 snapshot by using the zfs destroy command return EBUSY.
1873
1874 -r Recursively releases a hold with the given tag on the snapshots of
1875 all descendent file systems.
1876
1877 zfs diff [-FHt] snapshot snapshot|filesystem
1878 Display the difference between a snapshot of a given filesystem and
1879 another snapshot of that filesystem from a later time or the current
1880 contents of the filesystem. The first column is a character indicating
1881 the type of change, the other columns indicate pathname, new pathname
1882 (in case of rename), change in link count, and optionally file type
1883 and/or change time. The types of change are:
1884
1885 - The path has been removed
1886 + The path has been created
1887 M The path has been modified
1888 R The path has been renamed
1889
1890 -F Display an indication of the type of file, in a manner similar to
1891 the - option of ls(1).
1892
1893 B Block device
1894 C Character device
1895 / Directory
1896 > Door
1897 | Named pipe
1898 @ Symbolic link
1899 P Event port
1900 = Socket
1901 F Regular file
1902
1903 -H Give more parsable tab-separated output, without header lines and
1904 without arrows.
1905
1906 -t Display the path's inode change time as the first column of output.
1907
1908 EXIT STATUS
1909 The zfs utility exits 0 on success, 1 if an error occurs, and 2 if
1910 invalid command line options were specified.
1911
1912 EXAMPLES
1913 Example 1 Creating a ZFS File System Hierarchy
1914 The following commands create a file system named pool/home and a file
1915 system named pool/home/bob. The mount point /export/home is set for
1916 the parent file system, and is automatically inherited by the child
1917 file system.
1918
1919 # zfs create pool/home
1920 # zfs set mountpoint=/export/home pool/home
1921 # zfs create pool/home/bob
1922
1923 Example 2 Creating a ZFS Snapshot
1924 The following command creates a snapshot named yesterday. This
1925 snapshot is mounted on demand in the .zfs/snapshot directory at the
1926 root of the pool/home/bob file system.
1927
1928 # zfs snapshot pool/home/bob@yesterday
1929
1930 Example 3 Creating and Destroying Multiple Snapshots
1931 The following command creates snapshots named yesterday of pool/home
1932 and all of its descendent file systems. Each snapshot is mounted on
1933 demand in the .zfs/snapshot directory at the root of its file system.
1934 The second command destroys the newly created snapshots.
1935
1936 # zfs snapshot -r pool/home@yesterday
1937 # zfs destroy -r pool/home@yesterday
1938
1939 Example 4 Disabling and Enabling File System Compression
1940 The following command disables the compression property for all file
1941 systems under pool/home. The next command explicitly enables
1942 compression for pool/home/anne.
1943
1944 # zfs set compression=off pool/home
1945 # zfs set compression=on pool/home/anne
1946
1947 Example 5 Listing ZFS Datasets
1948 The following command lists all active file systems and volumes in the
1949 system. Snapshots are displayed if the listsnaps property is on. The
1950 default is off. See zpool(1M) for more information on pool properties.
1951
1952 # zfs list
1953 NAME USED AVAIL REFER MOUNTPOINT
1954 pool 450K 457G 18K /pool
1955 pool/home 315K 457G 21K /export/home
1956 pool/home/anne 18K 457G 18K /export/home/anne
1957 pool/home/bob 276K 457G 276K /export/home/bob
1958
1959 Example 6 Setting a Quota on a ZFS File System
1960 The following command sets a quota of 50 Gbytes for pool/home/bob.
1961
1962 # zfs set quota=50G pool/home/bob
1963
1964 Example 7 Listing ZFS Properties
1965 The following command lists all properties for pool/home/bob.
1966
1967 # zfs get all pool/home/bob
1968 NAME PROPERTY VALUE SOURCE
1969 pool/home/bob type filesystem -
1970 pool/home/bob creation Tue Jul 21 15:53 2009 -
1971 pool/home/bob used 21K -
1972 pool/home/bob available 20.0G -
1973 pool/home/bob referenced 21K -
1974 pool/home/bob compressratio 1.00x -
1975 pool/home/bob mounted yes -
1976 pool/home/bob quota 20G local
1977 pool/home/bob reservation none default
1978 pool/home/bob recordsize 128K default
1979 pool/home/bob mountpoint /pool/home/bob default
1980 pool/home/bob sharenfs off default
1981 pool/home/bob checksum on default
1982 pool/home/bob compression on local
1983 pool/home/bob atime on default
1984 pool/home/bob devices on default
1985 pool/home/bob exec on default
1986 pool/home/bob setuid on default
1987 pool/home/bob readonly off default
1988 pool/home/bob zoned off default
1989 pool/home/bob snapdir hidden default
1990 pool/home/bob aclmode discard default
1991 pool/home/bob aclinherit restricted default
1992 pool/home/bob canmount on default
1993 pool/home/bob xattr on default
1994 pool/home/bob copies 1 default
1995 pool/home/bob version 4 -
1996 pool/home/bob utf8only off -
1997 pool/home/bob normalization none -
1998 pool/home/bob casesensitivity sensitive -
1999 pool/home/bob vscan off default
2000 pool/home/bob nbmand off default
2001 pool/home/bob sharesmb off default
2002 pool/home/bob refquota none default
2003 pool/home/bob refreservation none default
2004 pool/home/bob primarycache all default
2005 pool/home/bob secondarycache all default
2006 pool/home/bob usedbysnapshots 0 -
2007 pool/home/bob usedbydataset 21K -
2008 pool/home/bob usedbychildren 0 -
2009 pool/home/bob usedbyrefreservation 0 -
2010
2011 The following command gets a single property value.
2012
2013 # zfs get -H -o value compression pool/home/bob
2014 on
2015 The following command lists all properties with local settings for
2016 pool/home/bob.
2017
2018 # zfs get -r -s local -o name,property,value all pool/home/bob
2019 NAME PROPERTY VALUE
2020 pool/home/bob quota 20G
2021 pool/home/bob compression on
2022
2023 Example 8 Rolling Back a ZFS File System
2024 The following command reverts the contents of pool/home/anne to the
2025 snapshot named yesterday, deleting all intermediate snapshots.
2026
2027 # zfs rollback -r pool/home/anne@yesterday
2028
2029 Example 9 Creating a ZFS Clone
2030 The following command creates a writable file system whose initial
2031 contents are the same as pool/home/bob@yesterday.
2032
2033 # zfs clone pool/home/bob@yesterday pool/clone
2034
2035 Example 10 Promoting a ZFS Clone
2036 The following commands illustrate how to test out changes to a file
2037 system, and then replace the original file system with the changed one,
2038 using clones, clone promotion, and renaming:
2039
2040 # zfs create pool/project/production
2041 populate /pool/project/production with data
2042 # zfs snapshot pool/project/production@today
2043 # zfs clone pool/project/production@today pool/project/beta
2044 make changes to /pool/project/beta and test them
2045 # zfs promote pool/project/beta
2046 # zfs rename pool/project/production pool/project/legacy
2047 # zfs rename pool/project/beta pool/project/production
2048 once the legacy version is no longer needed, it can be destroyed
2049 # zfs destroy pool/project/legacy
2050
2051 Example 11 Inheriting ZFS Properties
2052 The following command causes pool/home/bob and pool/home/anne to
2053 inherit the checksum property from their parent.
2054
2055 # zfs inherit checksum pool/home/bob pool/home/anne
2056
2057 Example 12 Remotely Replicating ZFS Data
2058 The following commands send a full stream and then an incremental
2059 stream to a remote machine, restoring them into poolB/received/fs@a and
2060 poolB/received/fs@b, respectively. poolB must contain the file system
2061 poolB/received, and must not initially contain poolB/received/fs.
2062
2063 # zfs send pool/fs@a | \
2064 ssh host zfs receive poolB/received/fs@a
2065 # zfs send -i a pool/fs@b | \
2066 ssh host zfs receive poolB/received/fs
2067
2068 Example 13 Using the zfs receive -d Option
2069 The following command sends a full stream of poolA/fsA/fsB@snap to a
2070 remote machine, receiving it into poolB/received/fsA/fsB@snap. The
2071 fsA/fsB@snap portion of the received snapshot's name is determined from
2072 the name of the sent snapshot. poolB must contain the file system
2073 poolB/received. If poolB/received/fsA does not exist, it is created as
2074 an empty file system.
2075
2076 # zfs send poolA/fsA/fsB@snap | \
2077 ssh host zfs receive -d poolB/received
2078
2079 Example 14 Setting User Properties
2080 The following example sets the user-defined com.example:department
2081 property for a dataset.
2082
2083 # zfs set com.example:department=12345 tank/accounting
2084
2085 Example 15 Performing a Rolling Snapshot
2086 The following example shows how to maintain a history of snapshots with
2087 a consistent naming scheme. To keep a week's worth of snapshots, the
2088 user destroys the oldest snapshot, renames the remaining snapshots, and
2089 then creates a new snapshot, as follows:
2090
2091 # zfs destroy -r pool/users@7daysago
2092 # zfs rename -r pool/users@6daysago @7daysago
2093 # zfs rename -r pool/users@5daysago @6daysago
2094 # zfs rename -r pool/users@yesterday @5daysago
2095 # zfs rename -r pool/users@yesterday @4daysago
2096 # zfs rename -r pool/users@yesterday @3daysago
2097 # zfs rename -r pool/users@yesterday @2daysago
2098 # zfs rename -r pool/users@today @yesterday
2099 # zfs snapshot -r pool/users@today
2100
2101 Example 16 Setting sharenfs Property Options on a ZFS File System
2102 The following commands show how to set sharenfs property options to
2103 enable rw access for a set of IP addresses and to enable root access
2104 for system neo on the tank/home file system.
2105
2106 # zfs set sharenfs='rw=@123.123.0.0/16,root=neo' tank/home
2107
2108 If you are using DNS for host name resolution, specify the fully
2109 qualified hostname.
2110
2111 Example 17 Delegating ZFS Administration Permissions on a ZFS Dataset
2112 The following example shows how to set permissions so that user cindys
2113 can create, destroy, mount, and take snapshots on tank/cindys. The
2114 permissions on tank/cindys are also displayed.
2115
2116 # zfs allow cindys create,destroy,mount,snapshot tank/cindys
2117 # zfs allow tank/cindys
2118 ---- Permissions on tank/cindys --------------------------------------
2119 Local+Descendent permissions:
2120 user cindys create,destroy,mount,snapshot
2121
2122 Because the tank/cindys mount point permission is set to 755 by
2123 default, user cindys will be unable to mount file systems under
2124 tank/cindys. Add an ACE similar to the following syntax to provide
2125 mount point access:
2126
2127 # chmod A+user:cindys:add_subdirectory:allow /tank/cindys
2128
2129 Example 18 Delegating Create Time Permissions on a ZFS Dataset
2130 The following example shows how to grant anyone in the group staff to
2131 create file systems in tank/users. This syntax also allows staff
2132 members to destroy their own file systems, but not destroy anyone
2133 else's file system. The permissions on tank/users are also displayed.
2134
2135 # zfs allow staff create,mount tank/users
2136 # zfs allow -c destroy tank/users
2137 # zfs allow tank/users
2138 ---- Permissions on tank/users ---------------------------------------
2139 Permission sets:
2140 destroy
2141 Local+Descendent permissions:
2142 group staff create,mount
2143
2144 Example 19 Defining and Granting a Permission Set on a ZFS Dataset
2145 The following example shows how to define and grant a permission set on
2146 the tank/users file system. The permissions on tank/users are also
2147 displayed.
2148
2149 # zfs allow -s @pset create,destroy,snapshot,mount tank/users
2150 # zfs allow staff @pset tank/users
2151 # zfs allow tank/users
2152 ---- Permissions on tank/users ---------------------------------------
2153 Permission sets:
2154 @pset create,destroy,mount,snapshot
2155 Local+Descendent permissions:
2156 group staff @pset
2157
2158 Example 20 Delegating Property Permissions on a ZFS Dataset
2159 The following example shows to grant the ability to set quotas and
2160 reservations on the users/home file system. The permissions on
2161 users/home are also displayed.
2162
2163 # zfs allow cindys quota,reservation users/home
2164 # zfs allow users/home
2165 ---- Permissions on users/home ---------------------------------------
2166 Local+Descendent permissions:
2167 user cindys quota,reservation
2168 cindys% zfs set quota=10G users/home/marks
2169 cindys% zfs get quota users/home/marks
2170 NAME PROPERTY VALUE SOURCE
2171 users/home/marks quota 10G local
2172
2173 Example 21 Removing ZFS Delegated Permissions on a ZFS Dataset
2174 The following example shows how to remove the snapshot permission from
2175 the staff group on the tank/users file system. The permissions on
2176 tank/users are also displayed.
2177
2178 # zfs unallow staff snapshot tank/users
2179 # zfs allow tank/users
2180 ---- Permissions on tank/users ---------------------------------------
2181 Permission sets:
2182 @pset create,destroy,mount,snapshot
2183 Local+Descendent permissions:
2184 group staff @pset
2185
2186 Example 22 Showing the differences between a snapshot and a ZFS Dataset
2187 The following example shows how to see what has changed between a prior
2188 snapshot of a ZFS dataset and its current state. The -F option is used
2189 to indicate type information for the files affected.
2190
2191 # zfs diff -F tank/test@before tank/test
2192 M / /tank/test/
2193 M F /tank/test/linked (+1)
2194 R F /tank/test/oldname -> /tank/test/newname
2195 - F /tank/test/deleted
2196 + F /tank/test/created
2197 M F /tank/test/modified
2198
2199 INTERFACE STABILITY
2200 Commited.
2201
2202 SEE ALSO
2203 gzip(1), ssh(1), mount(1M), share(1M), sharemgr(1M), unshare(1M),
2204 zonecfg(1M), zpool(1M), chmod(2), stat(2), write(2), fsync(3C),
2205 dfstab(4), acl(5), attributes(5)
2206
2207 illumos December 29, 2015 illumos