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31 .TH zfs 8 "May 11, 2016" "ZFS pool 28, filesystem 5" "System Administration Commands"
33 zfs \- configures ZFS file systems
42 \fBzfs\fR \fBcreate\fR [\fB-p\fR] [\fB-o\fR \fIproperty\fR=\fIvalue\fR] ... \fIfilesystem\fR
47 \fBzfs\fR \fBcreate\fR [\fB-ps\fR] [\fB-b\fR \fIblocksize\fR] [\fB-o\fR \fIproperty\fR=\fIvalue\fR] ... \fB-V\fR \fIsize\fR \fIvolume\fR
52 \fBzfs\fR \fBdestroy\fR [\fB-fnpRrv\fR] \fIfilesystem\fR|\fIvolume\fR
57 \fBzfs\fR \fBdestroy\fR [\fB-dnpRrv\fR] \fIfilesystem\fR|\fIvolume\fR@\fIsnap\fR[%\fIsnap\fR][,...]
62 \fBzfs\fR \fBdestroy\fR \fIfilesystem\fR|\fIvolume\fR#\fIbookmark\fR
67 \fBzfs\fR \fBsnapshot | snap\fR [\fB-r\fR] [\fB-o\fR \fIproperty\fR=\fIvalue\fR] ...
68 \fIfilesystem@snapname\fR|\fIvolume@snapname\fR ...
73 \fBzfs\fR \fBrollback\fR [\fB-rRf\fR] \fIsnapshot\fR
78 \fBzfs\fR \fBclone\fR [\fB-p\fR] [\fB-o\fR \fIproperty\fR=\fIvalue\fR] ... \fIsnapshot\fR \fIfilesystem\fR|\fIvolume\fR
83 \fBzfs\fR \fBpromote\fR \fIclone-filesystem\fR
88 \fBzfs\fR \fBrename\fR [\fB-f\fR] \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR
89 \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR
94 \fBzfs\fR \fBrename\fR [\fB-fp\fR] \fIfilesystem\fR|\fIvolume\fR \fIfilesystem\fR|\fIvolume\fR
99 \fBzfs\fR \fBrename\fR \fB-r\fR \fIsnapshot\fR \fIsnapshot\fR
104 \fBzfs\fR \fBlist\fR [\fB-r\fR|\fB-d\fR \fIdepth\fR][\fB-Hp\fR][\fB-o\fR \fIproperty\fR[,\fIproperty\fR]...] [\fB-t\fR \fItype\fR[,\fItype\fR]..]
105 [\fB-s\fR \fIproperty\fR] ... [\fB-S\fR \fIproperty\fR] ... [\fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR|\fImountpoint\fR] ...
110 +\fBzfs\fR \fBset\fR \fIproperty\fR=\fIvalue\fR... \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR...
115 \fBzfs\fR \fBget\fR [\fB-r\fR|\fB-d\fR \fIdepth\fR][\fB-Hp\fR][\fB-o\fR \fIfield\fR[,...]] [\fB-t\fR \fItype\fR[,...]]
116 [\fB-s\fR \fIsource\fR[,...]] "\fIall\fR" | \fIproperty\fR[,...] \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR|\fImountpoint\fR ...
121 \fBzfs\fR \fBinherit\fR [\fB-rS\fR] \fIproperty\fR \fIfilesystem\fR|\fIvolume|snapshot\fR ...
126 \fBzfs\fR \fBupgrade\fR [\fB-v\fR]
131 \fBzfs\fR \fBupgrade\fR [\fB-r\fR] [\fB-V\fR \fIversion\fR] \fB-a\fR | \fIfilesystem\fR
136 \fBzfs\fR \fBuserspace\fR [\fB-Hinp\fR] [\fB-o\fR \fIfield\fR[,...]] [\fB-s\fR \fIfield\fR] ...
137 [\fB-S\fR \fIfield\fR] ... [\fB-t\fR \fItype\fR[,...]] \fIfilesystem\fR|\fIsnapshot\fR
142 \fBzfs\fR \fBgroupspace\fR [\fB-Hinp\fR] [\fB-o\fR \fIfield\fR[,...]] [\fB-s\fR \fIfield\fR] ...
143 [\fB-S\fR \fIfield\fR] ... [\fB-t\fR \fItype\fR[,...]] \fIfilesystem\fR|\fIsnapshot\fR
148 \fBzfs\fR \fBmount\fR
153 \fBzfs\fR \fBmount\fR [\fB-vO\fR] [\fB-o \fIoptions\fR\fR] \fB-a\fR | \fIfilesystem\fR
158 \fBzfs\fR \fBunmount | umount\fR [\fB-f\fR] \fB-a\fR | \fIfilesystem\fR|\fImountpoint\fR
163 \fBzfs\fR \fBshare\fR \fB-a\fR | \fIfilesystem\fR
168 \fBzfs\fR \fBunshare\fR \fB-a\fR \fIfilesystem\fR|\fImountpoint\fR
173 \fBzfs\fR \fBbookmark\fR \fIsnapshot\fR \fIbookmark\fR
178 \fBzfs\fR \fBsend\fR [\fB-DnPpRveLc\fR] [\fB-\fR[\fBiI\fR] \fIsnapshot\fR] \fIsnapshot\fR
183 \fBzfs\fR \fBsend\fR [\fB-Le\fR] [\fB-i \fIsnapshot\fR|\fIbookmark\fR]\fR \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR
188 \fBzfs\fR \fBsend\fR [\fB-Penv\fR] \fB-t\fR \fIreceive_resume_token\fR
193 \fBzfs\fR \fBreceive\fR [\fB-Fnsuv\fR] [\fB-o origin\fR=\fIsnapshot\fR] \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR
198 \fBzfs\fR \fBreceive\fR [\fB-Fnsuv\fR] [\fB-d\fR|\fB-e\fR] [\fB-o origin\fR=\fIsnapshot\fR] \fIfilesystem\fR
203 \fBzfs\fR \fBreceive\fR \fB-A\fR \fIfilesystem\fR|\fIvolume\fR
208 \fBzfs\fR \fBallow\fR \fIfilesystem\fR|\fIvolume\fR
213 \fBzfs\fR \fBallow\fR [\fB-ldug\fR] "\fIeveryone\fR"|\fIuser\fR|\fIgroup\fR[,...] \fIperm\fR|\fI@setname\fR[,...]
214 \fIfilesystem\fR|\fIvolume\fR
219 \fBzfs\fR \fBallow\fR [\fB-ld\fR] \fB-e\fR \fIperm\fR|@\fIsetname\fR[,...] \fIfilesystem\fR|\fIvolume\fR
224 \fBzfs\fR \fBallow\fR \fB-c\fR \fIperm\fR|@\fIsetname\fR[,...] \fIfilesystem\fR|\fIvolume\fR
229 \fBzfs\fR \fBallow\fR \fB-s\fR @\fIsetname\fR \fIperm\fR|@\fIsetname\fR[,...] \fIfilesystem\fR|\fIvolume\fR
234 \fBzfs\fR \fBunallow\fR [\fB-rldug\fR] "\fIeveryone\fR"|\fIuser\fR|\fIgroup\fR[,...] [\fIperm\fR|@\fIsetname\fR[,... ]]
235 \fIfilesystem\fR|\fIvolume\fR
240 \fBzfs\fR \fBunallow\fR [\fB-rld\fR] \fB-e\fR [\fIperm\fR|@\fIsetname\fR[,... ]] \fIfilesystem\fR|\fIvolume\fR
245 \fBzfs\fR \fBunallow\fR [\fB-r\fR] \fB-c\fR [\fIperm\fR|@\fIsetname\fR[ ... ]] \fIfilesystem\fR|\fIvolume\fR
250 \fBzfs\fR \fBunallow\fR [\fB-r\fR] \fB-s\fR @\fIsetname\fR [\fIperm\fR|@\fIsetname\fR[,... ]] \fIfilesystem\fR|\fIvolume\fR
255 \fBzfs\fR \fBhold\fR [\fB-r\fR] \fItag\fR \fIsnapshot\fR...
260 \fBzfs\fR \fBholds\fR [\fB-r\fR] \fIsnapshot\fR...
265 \fBzfs\fR \fBrelease\fR [\fB-r\fR] \fItag\fR \fIsnapshot\fR...
270 \fBzfs\fR \fBdiff\fR [\fB-FHt\fR] \fIsnapshot\fR \fIsnapshot|filesystem\fR
274 The \fBzfs\fR command configures \fBZFS\fR datasets within a \fBZFS\fR storage pool, as described in \fBzpool\fR(8). A dataset is identified by a unique path within the \fBZFS\fR namespace. For example:
278 pool/{filesystem,volume,snapshot}
285 where the maximum length of a dataset name is \fBMAXNAMELEN\fR (256 bytes).
288 A dataset can be one of the following:
292 \fB\fIfilesystem\fR\fR
296 A \fBZFS\fR dataset of type \fBfilesystem\fR can be mounted within the standard system namespace and behaves like other file systems. While \fBZFS\fR file systems are designed to be \fBPOSIX\fR compliant, known issues exist that prevent compliance in some cases. Applications that depend on standards conformance might fail due to nonstandard behavior when checking file system free space.
306 A logical volume exported as a raw or block device. This type of dataset should only be used under special circumstances. File systems are typically used in most environments.
316 A read-only version of a file system or volume at a given point in time. It is specified as \fIfilesystem@name\fR or \fIvolume@name\fR.
326 Much like a \fIsnapshot\fR, but without the hold on on-disk data. It can be used as the source of a send (but not for a receive).
327 It is specified as \fIfilesystem#name\fR or \fIvolume#name\fR.
330 .SS "ZFS File System Hierarchy"
332 A \fBZFS\fR storage pool is a logical collection of devices that provide space for datasets. A storage pool is also the root of the \fBZFS\fR file system hierarchy.
335 The root of the pool can be accessed as a file system, such as mounting and unmounting, taking snapshots, and setting properties. The physical storage characteristics, however, are managed by the \fBzpool\fR(8) command.
338 See \fBzpool\fR(8) for more information on creating and administering pools.
341 A snapshot is a read-only copy of a file system or volume. Snapshots can be created extremely quickly, and initially consume no additional space within the pool. As data within the active dataset changes, the snapshot consumes more data than would otherwise be shared with the active dataset.
344 Snapshots can have arbitrary names. Snapshots of volumes can be cloned or rolled back. Visibility is determined by the \fBsnapdev\fR property of the parent volume.
347 File system snapshots can be accessed under the \fB\&.zfs/snapshot\fR directory in the root of the file system. Snapshots are automatically mounted on demand and may be unmounted at regular intervals. The visibility of the \fB\&.zfs\fR directory can be controlled by the \fBsnapdir\fR property.
350 A bookmark is like a snapshot, a read-only copy of a file system or volume. Bookmarks can be created extremely quickly, compared to snapshots, and they consume no additional space within the pool. Bookmarks can also have arbitrary names, much like snapshots.
353 Unlike snapshots, bookmarks can not be accessed through the filesystem in any way. From a storage standpoint a bookmark just provides a way to reference when a snapshot was created as a distinct object. Bookmarks are initially tied to a snapshot, not the filesystem/volume, and they will survive if the snapshot itself is destroyed. Since they are very light weight there's little incentive to destroy them.
356 A clone is a writable volume or file system whose initial contents are the same as another dataset. As with snapshots, creating a clone is nearly instantaneous, and initially consumes no additional space.
359 Clones can only be created from a snapshot. When a snapshot is cloned, it creates an implicit dependency between the parent and child. Even though the clone is created somewhere else in the dataset hierarchy, the original snapshot cannot be destroyed as long as a clone exists. The \fBorigin\fR property exposes this dependency, and the \fBdestroy\fR command lists any such dependencies, if they exist.
362 The clone parent-child dependency relationship can be reversed by using the \fBpromote\fR subcommand. This causes the "origin" file system to become a clone of the specified file system, which makes it possible to destroy the file system that the clone was created from.
365 Creating a \fBZFS\fR file system is a simple operation, so the number of file systems per system is likely to be numerous. To cope with this, \fBZFS\fR automatically manages mounting and unmounting file systems without the need to edit the \fB/etc/fstab\fR file. All automatically managed file systems are mounted by \fBZFS\fR at boot time.
368 By default, file systems are mounted under \fB/\fIpath\fR\fR, where \fIpath\fR is the name of the file system in the \fBZFS\fR namespace. Directories are created and destroyed as needed.
371 A file system can also have a mount point set in the \fBmountpoint\fR property. This directory is created as needed, and \fBZFS\fR automatically mounts the file system when the \fBzfs mount -a\fR command is invoked (without editing \fB/etc/fstab\fR). The \fBmountpoint\fR property can be inherited, so if \fBpool/home\fR has a mount point of \fB/export/stuff\fR, then \fBpool/home/user\fR automatically inherits a mount point of \fB/export/stuff/user\fR.
374 A file system \fBmountpoint\fR property of \fBnone\fR prevents the file system from being mounted.
377 If needed, \fBZFS\fR file systems can also be managed with traditional tools (\fBmount\fR, \fBumount\fR, \fB/etc/fstab\fR). If a file system's mount point is set to \fBlegacy\fR, \fBZFS\fR makes no attempt to manage the file system, and the administrator is responsible for mounting and unmounting the file system.
380 Deduplication is the process for removing redundant data at the block-level, reducing the total amount of data stored. If a file system has the \fBdedup\fR property enabled, duplicate data blocks are removed synchronously. The result is that only unique data is stored and common components are shared among files.
382 \fBWARNING: DO NOT ENABLE DEDUPLICATION UNLESS YOU NEED IT AND KNOW EXACTLY WHAT YOU ARE DOING!\fR
384 Deduplicating data is a very resource-intensive operation. It is generally recommended that you have \fIat least\fR 1.25 GiB of RAM per 1 TiB of storage when you enable deduplication. But calculating the exact requirements is a somewhat complicated affair.
386 Enabling deduplication on an improperly-designed system will result in extreme performance issues (extremely slow filesystem and snapshot deletions etc.) and can potentially lead to data loss (i.e. unimportable pool due to memory exhaustion) if your system is not built for this purpose. Deduplication affects the processing power (CPU), disks (and the controller) as well as primary (real) memory.
388 Before creating a pool with deduplication enabled, ensure that you have planned your hardware requirements appropriately and implemented appropriate recovery practices, such as regular backups.
390 Unless necessary, deduplication should NOT be enabled on a system. Instead, consider using \fIcompression=lz4\fR, as a less resource-intensive alternative.
394 Properties are divided into two types: native properties and user-defined (or "user") properties. Native properties either export internal statistics or control \fBZFS\fR behavior. User properties have no effect on \fBZFS\fR behavior, but you can use them to annotate datasets and snapshots in a way that is meaningful in your environment.
397 Properties are generally inherited from the parent unless overridden by the child. See the documentation below for exceptions.
400 .SS "Native Properties"
401 Native properties apply to all dataset types unless otherwise noted. However, native properties cannot be edited on snapshots.
404 The values of numeric native properties can be specified using human-readable abbreviations (\fBK\fR, \fBM\fR, \fBG\fR, \fBT\fR, \fBP\fR, \fBE\fR, and \fBZ\fR). These abbreviations can optionally use the IEC binary prefixes (e.g. GiB) or SI decimal prefixes (e.g. GB), though the SI prefixes are treated as binary prefixes. Abbreviations are case-insensitive. The following are all valid (and equal) specifications:
408 1536M, 1.5g, 1.50GB, 1.5GiB
415 The values of non-numeric native properties are case-sensitive and must be lowercase, except for \fBmountpoint\fR, \fBsharenfs\fR, and \fBsharesmb\fR.
418 The following native properties consist of read-only statistics about the dataset. These properties can be neither set, nor inherited.
422 \fB\fBavailable\fR\fR
426 The amount of space available to the dataset and all its children, assuming that there is no other activity in the pool. Because space is shared within a pool, availability can be limited by any number of factors, including physical pool size, quotas, reservations, or other datasets within the pool.
428 This property can also be referred to by its shortened column name, \fBavail\fR.
434 \fB\fBcompressratio\fR\fR
438 For non-snapshots, the compression ratio achieved for the \fBused\fR space of this dataset, expressed as a multiplier. The \fBused\fR property includes descendant datasets, and, for clones, does not include the space shared with the origin snapshot. For snapshots, the \fBcompressratio\fR is the same as the \fBrefcompressratio\fR property. The \fBcompression\fR property controls whether compression is enabled on a dataset.
448 The time this dataset was created.
458 For snapshots, this property is a comma-separated list of filesystems or
459 volumes which are clones of this snapshot. The clones' \fBorigin\fR property
460 is this snapshot. If the \fBclones\fR property is not empty, then this
461 snapshot can not be destroyed (even with the \fB-r\fR or \fB-f\fR options). The
462 roles of origin and clone can be swapped by promoting the clone with the
463 \fBzfs promote\fR command.
469 \fB\fBdefer_destroy\fR\fR
473 This property is \fBon\fR if the snapshot has been marked for deferred destruction by using the \fBzfs destroy\fR \fB-d\fR command. Otherwise, the property is \fBoff\fR.
479 \fB\fBfilesystem_count\fR
483 The total number of filesystems and volumes that exist under this location in the
484 dataset tree. This value is only available when a \fBfilesystem_limit\fR has
485 been set somewhere in the tree under which the dataset resides.
491 \fB\fBlogicalreferenced\fR\fR
495 The amount of space that is "logically" accessible by this dataset. See
496 the \fBreferenced\fR property. The logical space ignores the effect of
497 the \fBcompression\fR and \fBcopies\fR properties, giving a quantity
498 closer to the amount of data that applications see. However, it does
499 include space consumed by metadata.
501 This property can also be referred to by its shortened column name,
508 \fB\fBlogicalused\fR\fR
512 The amount of space that is "logically" consumed by this dataset and all
513 its descendents. See the \fBused\fR property. The logical space
514 ignores the effect of the \fBcompression\fR and \fBcopies\fR properties,
515 giving a quantity closer to the amount of data that applications see.
516 However, it does include space consumed by metadata.
518 This property can also be referred to by its shortened column name,
529 For file systems, indicates whether the file system is currently mounted. This property can be either \fByes\fR or \fBno\fR.
539 For cloned file systems or volumes, the snapshot from which the clone was created. The origin cannot be destroyed (even with the \fB-r\fR or \fB-f\fR options) so long as a clone exists. See also the \fBclones\fR property.
545 \fB\fBreceive_resume_token\fR\fR
549 For filesystems or volumes which have saved partially-completed state from \fBzfs receive -s\fR , this opaque token can be provided to \fBzfs send -t\fR to resume and complete the \fBzfs receive\fR.
556 \fB\fBreferenced\fR\fR
560 The amount of data that is accessible by this dataset, which may or may not be shared with other datasets in the pool. When a snapshot or clone is created, it initially references the same amount of space as the file system or snapshot it was created from, since its contents are identical.
562 This property can also be referred to by its shortened column name, \fBrefer\fR.
568 \fB\fBrefcompressratio\fR\fR
572 The compression ratio achieved for the \fBreferenced\fR space of this
573 dataset, expressed as a multiplier. See also the \fBcompressratio\fR
580 \fB\fBsnapshot_count\fR
584 The total number of snapshots that exist under this location in the dataset tree.
585 This value is only available when a \fBsnapshot_limit\fR has been set somewhere
586 in the tree under which the dataset resides.
596 The type of dataset: \fBfilesystem\fR, \fBvolume\fR, or \fBsnapshot\fR.
606 The amount of space consumed by this dataset and all its descendents. This is the value that is checked against this dataset's quota and reservation. The space used does not include this dataset's reservation, but does take into account the reservations of any descendent datasets. The amount of space that a dataset consumes from its parent, as well as the amount of space that are freed if this dataset is recursively destroyed, is the greater of its space used and its reservation.
608 When snapshots (see the "Snapshots" section) are created, their space is initially shared between the snapshot and the file system, and possibly with previous snapshots. As the file system changes, space that was previously shared becomes unique to the snapshot, and counted in the snapshot's space used. Additionally, deleting snapshots can increase the amount of space unique to (and used by) other snapshots.
610 The amount of space used, available, or referenced does not take into account pending changes. Pending changes are generally accounted for within a few seconds. Committing a change to a disk using \fBfsync\fR(2) or \fBO_SYNC\fR (see \fBopen\fR(2)) does not necessarily guarantee that the space usage information is updated immediately.
620 The \fBusedby*\fR properties decompose the \fBused\fR properties into the various reasons that space is used. Specifically, \fBused\fR = \fBusedbychildren\fR + \fBusedbydataset\fR + \fBusedbyrefreservation\fR + \fBusedbysnapshots\fR. These properties are only available for datasets created on \fBzpool\fR version 13 or higher pools.
626 \fB\fBusedbychildren\fR\fR
630 The amount of space used by children of this dataset, which would be freed if all the dataset's children were destroyed.
636 \fB\fBusedbydataset\fR\fR
640 The amount of space used by this dataset itself, which would be freed if the dataset were destroyed (after first removing any \fBrefreservation\fR and destroying any necessary snapshots or descendents).
646 \fB\fBusedbyrefreservation\fR\fR
650 The amount of space used by a \fBrefreservation\fR set on this dataset, which would be freed if the \fBrefreservation\fR was removed.
656 \fB\fBusedbysnapshots\fR\fR
660 The amount of space consumed by snapshots of this dataset. In particular, it is the amount of space that would be freed if all of this dataset's snapshots were destroyed. Note that this is not simply the sum of the snapshots' \fBused\fR properties because space can be shared by multiple snapshots.
666 \fB\fBuserused@\fR\fIuser\fR\fR
670 The amount of space consumed by the specified user in this dataset. Space is charged to the owner of each file, as displayed by \fBls\fR \fB-l\fR. The amount of space charged is displayed by \fBdu\fR and \fBls\fR \fB-s\fR. See the \fBzfs userspace\fR subcommand for more information.
672 Unprivileged users can access only their own space usage. The root user, or a user who has been granted the \fBuserused\fR privilege with \fBzfs allow\fR, can access everyone's usage.
674 The \fBuserused@\fR... properties are not displayed by \fBzfs get all\fR. The user's name must be appended after the \fB@\fR symbol, using one of the following forms:
679 \fIPOSIX name\fR (for example, \fBjoe\fR)
685 \fIPOSIX numeric ID\fR (for example, \fB789\fR)
691 \fISID name\fR (for example, \fBjoe.smith@mydomain\fR)
697 \fISID numeric ID\fR (for example, \fBS-1-123-456-789\fR)
700 Files created on Linux always have POSIX owners.
709 This property is set to the number of user holds on this snapshot. User holds are set by using the \fBzfs hold\fR command.
715 \fB\fBgroupused@\fR\fIgroup\fR\fR
719 The amount of space consumed by the specified group in this dataset. Space is charged to the group of each file, as displayed by \fBls\fR \fB-l\fR. See the \fBuserused@\fR\fIuser\fR property for more information.
721 Unprivileged users can only access their own groups' space usage. The root user, or a user who has been granted the \fBgroupused\fR privilege with \fBzfs allow\fR, can access all groups' usage.
727 \fB\fBvolblocksize\fR=\fIblocksize\fR\fR
731 This property, which is only valid on volumes, specifies the block size of the volume. Any power of two from 512B to 128KiB is valid. The default is 8KiB.
733 This property cannot be changed after the volume is created.
735 This property can also be referred to by its shortened column name, \fBvolblock\fR.
745 The amount of \fBreferenced\fR space written to this dataset since the
752 \fB\fBwritten@\fR\fIsnapshot\fR\fR
756 The amount of \fBreferenced\fR space written to this dataset since the
757 specified snapshot. This is the space that is referenced by this dataset
758 but was not referenced by the specified snapshot.
760 The \fIsnapshot\fR may be specified as a short snapshot name (just the part
761 after the \fB@\fR), in which case it will be interpreted as a snapshot in
762 the same filesystem as this dataset.
763 The \fIsnapshot\fR be a full snapshot name (\fIfilesystem\fR@\fIsnapshot\fR),
764 which for clones may be a snapshot in the origin's filesystem (or the origin
765 of the origin's filesystem, etc).
770 The following native properties can be used to change the behavior of a \fBZFS\fR dataset.
774 \fB\fBaclinherit\fR=\fBrestricted\fR | \fBdiscard\fR | \fBnoallow\fR | \fBpassthrough\fR | \fBpassthrough-x\fR\fR
778 Controls how \fBACL\fR entries are inherited when files and directories are created. A file system with an \fBaclinherit\fR property of \fBdiscard\fR does not inherit any \fBACL\fR entries. A file system with an \fBaclinherit\fR property value of \fBnoallow\fR only inherits inheritable \fBACL\fR entries that specify "deny" permissions. The property value \fBrestricted\fR (the default) removes the \fBwrite_acl\fR and \fBwrite_owner\fR permissions when the \fBACL\fR entry is inherited. A file system with an \fBaclinherit\fR property value of \fBpassthrough\fR inherits all inheritable \fBACL\fR entries without any modifications made to the \fBACL\fR entries when they are inherited. A file system with an \fBaclinherit\fR property value of \fBpassthrough-x\fR has the same meaning as \fBpassthrough\fR, except that the \fBowner@\fR, \fBgroup@\fR, and \fBeveryone@\fR \fBACE\fRs inherit the execute permission only if the file creation mode also requests the execute bit.
780 When the property value is set to \fBpassthrough\fR, files are created with a mode determined by the inheritable \fBACE\fRs. If no inheritable \fBACE\fRs exist that affect the mode, then the mode is set in accordance to the requested mode from the application.
782 The \fBaclinherit\fR property does not apply to Posix ACLs.
788 \fB\fBacltype\fR=\fBoff\fR | \fBnoacl\fR | \fBposixacl\fR \fR
792 Controls whether ACLs are enabled and if so what type of ACL to use. When
793 a file system has the \fBacltype\fR property set to \fBoff\fR (the default)
794 then ACLs are disabled. Setting the \fBacltype\fR property to \fBposixacl\fR
795 indicates Posix ACLs should be used. Posix ACLs are specific to Linux and
796 are not functional on other platforms. Posix ACLs are stored as an xattr and
797 therefore will not overwrite any existing ZFS/NFSv4 ACLs which may be set.
798 Currently only \fBposixacls\fR are supported on Linux.
800 To obtain the best performance when setting \fBposixacl\fR users are strongly
801 encouraged to set the \fBxattr=sa\fR property. This will result in the
802 Posix ACL being stored more efficiently on disk. But as a consequence of this
803 all new xattrs will only be accessible from ZFS implementations which support
804 the \fBxattr=sa\fR property. See the \fBxattr\fR property for more details.
806 The value \fBnoacl\fR is an alias for \fBoff\fR.
812 \fB\fBatime\fR=\fBon\fR | \fBoff\fR\fR
816 Controls whether the access time for files is updated when they are read. Setting this property to \fBoff\fR avoids producing write traffic when reading files and can result in significant performance gains, though it might confuse mailers and other similar utilities. The default value is \fBon\fR. See also \fBrelatime\fR below.
818 The values \fBon\fR and \fBoff\fR are equivalent to the \fBatime\fR and \fBnoatime\fR mount options.
824 \fB\fBcanmount\fR=\fBon\fR | \fBoff\fR | \fBnoauto\fR\fR
828 If this property is set to \fBoff\fR, the file system cannot be mounted, and is ignored by \fBzfs mount -a\fR. Setting this property to \fBoff\fR is similar to setting the \fBmountpoint\fR property to \fBnone\fR, except that the dataset still has a normal \fBmountpoint\fR property, which can be inherited. Setting this property to \fBoff\fR allows datasets to be used solely as a mechanism to inherit properties. One example of setting \fBcanmount=\fR\fBoff\fR is to have two datasets with the same \fBmountpoint\fR, so that the children of both datasets appear in the same directory, but might have different inherited characteristics.
830 When the \fBnoauto\fR option is set, a dataset can only be mounted and unmounted explicitly. The dataset is not mounted automatically when the dataset is created or imported, nor is it mounted by the \fBzfs mount -a\fR command or unmounted by the \fBzfs unmount -a\fR command.
832 This property is not inherited. Every dataset defaults to \fBon\fR independently.
834 The values \fBon\fR and \fBnoauto\fR are equivalent to the \fBauto\fR and \fBnoauto\fR mount options.
840 \fB\fBchecksum\fR=\fBon\fR | \fBoff\fR | \fBfletcher2\fR | \fBfletcher4\fR | \fBsha256\fR\fR
844 Controls the checksum used to verify data integrity. The default value is \fBon\fR, which automatically selects an appropriate algorithm (currently, \fBfletcher4\fR, but this may change in future releases). The value \fBoff\fR disables integrity checking on user data. Disabling checksums is \fBNOT\fR a recommended practice.
846 Changing this property affects only newly-written data.
852 \fB\fBcompression\fR=\fBoff\fR | \fBon\fR | \fBlzjb\fR | \fBlz4\fR |
853 \fBgzip\fR | \fBgzip-\fR\fIN\fR | \fBzle\fR\fR
857 Controls the compression algorithm used for this dataset.
859 Setting compression to \fBon\fR indicates that the current default
860 compression algorithm should be used. The default balances compression
861 and decompression speed, with compression ratio and is expected to
862 work well on a wide variety of workloads. Unlike all other settings for
863 this property, \fBon\fR does not select a fixed compression type. As
864 new compression algorithms are added to ZFS and enabled on a pool, the
865 default compression algorithm may change. The current default compression
866 algorithm is either \fBlzjb\fR or, if the \fBlz4_compress\fR feature is
869 The \fBlzjb\fR compression algorithm is optimized for performance while
870 providing decent data compression.
872 The \fBlz4\fR compression algorithm is a high-performance replacement
873 for the \fBlzjb\fR algorithm. It features significantly faster
874 compression and decompression, as well as a moderately higher
875 compression ratio than \fBlzjb\fR, but can only be used on pools with
876 the \fBlz4_compress\fR feature set to \fIenabled\fR. See
877 \fBzpool-features\fR(5) for details on ZFS feature flags and the
878 \fBlz4_compress\fR feature.
880 The \fBgzip\fR compression algorithm uses the same compression as
881 the \fBgzip\fR(1) command. You can specify the \fBgzip\fR level by using the
882 value \fBgzip-\fR\fIN\fR where \fIN\fR is an integer from 1 (fastest) to 9
883 (best compression ratio). Currently, \fBgzip\fR is equivalent to \fBgzip-6\fR
884 (which is also the default for \fBgzip\fR(1)). The \fBzle\fR compression
885 algorithm compresses runs of zeros.
887 This property can also be referred to by its shortened column name
888 \fBcompress\fR. Changing this property affects only newly-written data.
894 \fB\fBcopies\fR=\fB1\fR | \fB2\fR | \fB3\fR\fR
898 Controls the number of copies of data stored for this dataset. These copies are in addition to any redundancy provided by the pool, for example, mirroring or RAID-Z. The copies are stored on different disks, if possible. The space used by multiple copies is charged to the associated file and dataset, changing the \fBused\fR property and counting against quotas and reservations.
900 Changing this property only affects newly-written data.
902 Remember that \fBZFS\fR will not import a pool with a missing top-level vdev. Do NOT create, for example, a two-disk, striped pool and set \fBcopies=\fR\fI2\fR on some datasets thinking you have setup redundancy for them. When one disk dies, you will not be able to import the pool and will have lost all of your data.
908 \fB\fBdedup\fR=\fBoff\fR | \fBon\fR | \fBverify\fR | \fBsha256\fR[,\fBverify\fR]\fR
912 Controls whether deduplication is in effect for a dataset. The default value is \fBoff\fR. The default checksum used for deduplication is \fBsha256\fR (subject to change). When \fBdedup\fR is enabled, the \fBdedup\fR checksum algorithm overrides the \fBchecksum\fR property. Setting the value to \fBverify\fR is equivalent to specifying \fBsha256,verify\fR.
914 If the property is set to \fBverify\fR, then, whenever two blocks have the same signature, ZFS will do a byte-for-byte comparison with the existing block to ensure that the contents are identical.
916 Unless necessary, deduplication should NOT be enabled on a system. See \fBDeduplication\fR above.
922 \fB\fBdevices\fR=\fBon\fR | \fBoff\fR\fR
926 Controls whether device nodes can be opened on this file system. The default value is \fBon\fR.
928 The values \fBon\fR and \fBoff\fR are equivalent to the \fBdev\fR and \fBnodev\fR mount options.
934 \fB\fBdnodesize\fR=\fBlegacy\fR | \fBauto\fR | \fB1k\fR | \fB2k\fR | \fB4k\fR | \fB8k\fR | \fB16k\fR\fR
938 Specifies a compatibility mode or literal value for the size of dnodes
939 in the file system. The default value is \fBlegacy\fR. Setting this
940 property to a value other than \fBlegacy\fR requires the
941 \fBlarge_dnode\fR pool feature to be enabled.
943 Consider setting \fBdnodesize\fR to \fBauto\fR if the dataset uses the
944 \fBxattr=sa\fR property setting and the workload makes heavy use of
945 extended attributes. This may be applicable to SELinux-enabled systems,
946 Lustre servers, and Samba servers, for example. Literal values are
947 supported for cases where the optimal size is known in advance and for
950 Leave \fBdnodesize\fR set to \fBlegacy\fR if you need to receive
951 a \fBzfs send\fR stream of this dataset on a pool that doesn't enable
952 the \fBlarge_dnode\fR feature, or if you need to import this pool on a
953 system that doesn't support the \fBlarge_dnode\fR feature.
955 This property can also be referred to by its shortened column name,
963 \fB\fBexec\fR=\fBon\fR | \fBoff\fR\fR
967 Controls whether processes can be executed from within this file system. The default value is \fBon\fR.
969 The values \fBon\fR and \fBoff\fR are equivalent to the \fBexec\fR and \fBnoexec\fR mount options.
975 \fB\fBmlslabel\fR=\fBnone\fR\fR | \fIlabel\fR
979 The \fBmlslabel\fR property is a sensitivity label that determines if a dataset can be mounted in a zone on a system with Trusted Extensions enabled. If the labeled dataset matches the labeled zone, the dataset can be mounted and accessed from the labeled zone.
981 When the \fBmlslabel\fR property is not set, the default value is \fBnone\fR. Setting the \fBmlslabel\fR property to \fBnone\fR is equivalent to removing the property.
983 The \fBmlslabel\fR property can be modified only when Trusted Extensions is enabled and only with appropriate privilege. Rights to modify it cannot be delegated. When changing a label to a higher label or setting the initial dataset label, the \fB{PRIV_FILE_UPGRADE_SL}\fR privilege is required. When changing a label to a lower label or the default (\fBnone\fR), the \fB{PRIV_FILE_DOWNGRADE_SL}\fR privilege is required. Changing the dataset to labels other than the default can be done only when the dataset is not mounted. When a dataset with the default label is mounted into a labeled-zone, the mount operation automatically sets the \fBmlslabel\fR property to the label of that zone.
985 When Trusted Extensions is \fBnot\fR enabled, only datasets with the default label (\fBnone\fR) can be mounted.
987 Zones are a Solaris feature and are not relevant on Linux.
993 \fB\fBfilesystem_limit\fR=\fBnone\fR\fR | \fIcount\fR
997 Limits the number of filesystems and volumes that can exist under this point in
998 the dataset tree. The limit is not enforced if the user is allowed to change
999 the limit. Setting a filesystem_limit on a descendent of a filesystem that
1000 already has a filesystem_limit does not override the ancestor's filesystem_limit,
1001 but rather imposes an additional limit. This feature must be enabled to be used
1002 (see \fBzpool-features\fR(5)).
1008 \fB\fBmountpoint\fR=\fIpath\fR | \fBnone\fR | \fBlegacy\fR\fR
1012 Controls the mount point used for this file system. See the "Mount Points" section for more information on how this property is used.
1014 When the \fBmountpoint\fR property is changed for a file system, the file system and any children that inherit the mount point are unmounted. If the new value is \fBlegacy\fR, then they remain unmounted. Otherwise, they are automatically remounted in the new location if the property was previously \fBlegacy\fR or \fBnone\fR, or if they were mounted before the property was changed. In addition, any shared file systems are unshared and shared in the new location.
1020 \fB\fBnbmand\fR=\fBoff\fR | \fBon\fR\fR
1024 Controls whether the file system should be mounted with \fBnbmand\fR (Non Blocking mandatory locks). This is used for \fBCIFS\fR clients. Changes to this property only take effect when the file system is umounted and remounted. See \fBmount\fR(1M) on a Solaris system for more information on \fBnbmand\fR mounts.
1026 The values \fBon\fR and \fBoff\fR are equivalent to the \fBnbmand\fR and \fBnonbmand\fR mount options.
1028 This property is not used on Linux.
1034 \fB\fBprimarycache\fR=\fBall\fR | \fBnone\fR | \fBmetadata\fR\fR
1038 Controls what is cached in the primary cache (ARC). If this property is set to \fBall\fR, then both user data and metadata is cached. If this property is set to \fBnone\fR, then neither user data nor metadata is cached. If this property is set to \fBmetadata\fR, then only metadata is cached. The default value is \fBall\fR.
1044 \fB\fBquota\fR=\fBnone\fR | \fIsize\fR\fR
1048 Limits the amount of space a dataset and its descendents can consume. This property enforces a hard limit on the amount of space used. This includes all space consumed by descendents, including file systems and snapshots. Setting a quota on a descendent of a dataset that already has a quota does not override the ancestor's quota, but rather imposes an additional limit.
1050 Quotas cannot be set on volumes, as the \fBvolsize\fR property acts as an implicit quota.
1056 \fB\fBsnapshot_limit\fR=\fBnone\fR\fR | \fIcount\fR
1060 Limits the number of snapshots that can be created on a dataset and its
1061 descendents. Setting a snapshot_limit on a descendent of a dataset that already
1062 has a snapshot_limit does not override the ancestor's snapshot_limit, but
1063 rather imposes an additional limit. The limit is not enforced if the user is
1064 allowed to change the limit. For example, this means that recursive snapshots
1065 taken from the global zone are counted against each delegated dataset within
1066 a zone. This feature must be enabled to be used (see \fBzpool-features\fR(5)).
1072 \fB\fBuserquota@\fR\fIuser\fR=\fBnone\fR | \fIsize\fR\fR
1076 Limits the amount of space consumed by the specified user. Similar to the \fBrefquota\fR property, the \fBuserquota\fR space calculation does not include space that is used by descendent datasets, such as snapshots and clones. User space consumption is identified by the \fBuserspace@\fR\fIuser\fR property. See the \fBzfs userspace\fR subcommand for more information.
1078 Enforcement of user quotas may be delayed by several seconds. This delay means that a user might exceed their quota before the system notices that they are over quota and begins to refuse additional writes with the \fBEDQUOT\fR error message.
1080 Unprivileged users can only access their own groups' space usage. The root user, or a user who has been granted the \fBuserquota\fR privilege with \fBzfs allow\fR, can get and set everyone's quota.
1082 This property is not available on volumes, on file systems before version 4, or on pools before version 15. The \fBuserquota@\fR... properties are not displayed by \fBzfs get all\fR. The user's name must be appended after the \fB@\fR symbol, using one of the following forms:
1087 \fIPOSIX name\fR (for example, \fBjoe\fR)
1093 \fIPOSIX numeric ID\fR (for example, \fB789\fR)
1099 \fISID name\fR (for example, \fBjoe.smith@mydomain\fR)
1105 \fISID numeric ID\fR (for example, \fBS-1-123-456-789\fR)
1108 Files created on Linux always have POSIX owners.
1113 \fB\fBgroupquota@\fR\fIgroup\fR=\fBnone\fR\fR | \fIsize\fR
1117 Limits the amount of space consumed by the specified group. Group space consumption is identified by the \fBuserquota@\fR\fIuser\fR property.
1119 Unprivileged users can access only their own groups' space usage. The root user, or a user who has been granted the \fBgroupquota\fR privilege with \fBzfs allow\fR, can get and set all groups' quotas.
1125 \fB\fBreadonly\fR=\fBoff\fR | \fBon\fR\fR
1129 Controls whether this dataset can be modified. The default value is \fBoff\fR.
1131 This property can also be referred to by its shortened column name, \fBrdonly\fR.
1133 The values \fBon\fR and \fBoff\fR are equivalent to the \fBro\fR and \fBrw\fR mount options.
1139 \fB\fBrecordsize\fR=\fIsize\fR\fR
1143 Specifies a suggested block size for files in the file system. This property is designed solely for use with database workloads that access files in fixed-size records. \fBZFS\fR automatically tunes block sizes according to internal algorithms optimized for typical access patterns.
1145 For databases that create very large files but access them in small random chunks, these algorithms may be suboptimal. Specifying a \fBrecordsize\fR greater than or equal to the record size of the database can result in significant performance gains. Use of this property for general purpose file systems is strongly discouraged, and may adversely affect performance.
1147 Any power of two from 512B to 1MiB is valid. The default is 128KiB. Values larger than 128KiB require the pool have the \fBlarge_blocks\fR feature enabled. See \fBzpool-features\fR(5) for details on ZFS feature flags and the \fBlarge_blocks\fR feature.
1149 Changing the file system's \fBrecordsize\fR affects only files created afterward; existing files are unaffected.
1151 This property can also be referred to by its shortened column name, \fBrecsize\fR.
1157 \fB\fBredundant_metadata\fR=\fBall\fR | \fBmost\fR\fR
1161 Controls what types of metadata are stored redundantly. ZFS stores an
1162 extra copy of metadata, so that if a single block is corrupted, the
1163 amount of user data lost is limited. This extra copy is in addition to
1164 any redundancy provided at the pool level (e.g. by mirroring or RAID-Z),
1165 and is in addition to an extra copy specified by the \fBcopies\fR
1166 property (up to a total of 3 copies). For example if the pool is
1167 mirrored, \fBcopies\fR=2, and \fBredundant_metadata\fR=most, then ZFS
1168 stores 6 copies of most metadata, and 4 copies of data and some
1171 When set to \fBall\fR, ZFS stores an extra copy of all metadata. If a
1172 single on-disk block is corrupt, at worst a single block of user data
1173 (which is \fBrecordsize\fR bytes long) can be lost.
1175 When set to \fBmost\fR, ZFS stores an extra copy of most types of
1176 metadata. This can improve performance of random writes, because less
1177 metadata must be written. In practice, at worst about 100 blocks (of
1178 \fBrecordsize\fR bytes each) of user data can be lost if a single
1179 on-disk block is corrupt. The exact behavior of which metadata blocks
1180 are stored redundantly may change in future releases.
1182 The default value is \fBall\fR.
1188 \fB\fBrefquota\fR=\fBnone\fR | \fIsize\fR\fR
1192 Limits the amount of space a dataset can consume. This property enforces a hard limit on the amount of space used. This hard limit does not include space used by descendents, including file systems and snapshots.
1198 \fB\fBrefreservation\fR=\fBnone\fR | \fIsize\fR\fR
1202 The minimum amount of space guaranteed to a dataset, not including its descendents. When the amount of space used is below this value, the dataset is treated as if it were taking up the amount of space specified by \fBrefreservation\fR. The \fBrefreservation\fR reservation is accounted for in the parent datasets' space used, and counts against the parent datasets' quotas and reservations.
1204 If \fBrefreservation\fR is set, a snapshot is only allowed if there is enough free pool space outside of this reservation to accommodate the current number of \fBreferenced\fR bytes in the dataset (which are the bytes to be referenced by the snapshot). This is necessary to continue to provide the \fBrefreservation\fRguarantee to the dataset.
1206 For volumes, see also \fBvolsize\fR.
1208 This property can also be referred to by its shortened column name, \fBrefreserv\fR.
1214 \fB\fBrelatime\fR=\fBoff\fR | \fBon\fR\fR
1218 Controls the manner in which the access time is updated when \fBatime=on\fR is set. Turning this property \fBon\fR causes the access time to be updated relative to the modify or change time. Access time is only updated if the previous access time was earlier than the current modify or change time or if the existing access time hasn't been updated within the past 24 hours. The default value is \fBoff\fR.
1220 The values \fBon\fR and \fBoff\fR are equivalent to the \fBrelatime\fR and \fBnorelatime\fR mount options.
1226 \fB\fBreservation\fR=\fBnone\fR | \fIsize\fR\fR
1230 The minimum amount of space guaranteed to a dataset and its descendents. When the amount of space used is below this value, the dataset is treated as if it were taking up the amount of space specified by its reservation. Reservations are accounted for in the parent datasets' space used, and count against the parent datasets' quotas and reservations.
1232 This property can also be referred to by its shortened column name, \fBreserv\fR.
1238 \fB\fBsecondarycache\fR=\fBall\fR | \fBnone\fR | \fBmetadata\fR\fR
1242 Controls what is cached in the secondary cache (L2ARC). If this property is set to \fBall\fR, then both user data and metadata is cached. If this property is set to \fBnone\fR, then neither user data nor metadata is cached. If this property is set to \fBmetadata\fR, then only metadata is cached. The default value is \fBall\fR.
1248 \fB\fBsetuid\fR=\fBon\fR | \fBoff\fR\fR
1252 Controls whether the setuid bit is respected for the file system. The default value is \fBon\fR.
1254 The values \fBon\fR and \fBoff\fR are equivalent to the \fBsuid\fR and \fBnosuid\fR mount options.
1260 \fB\fBsharesmb\fR=\fBoff\fR | \fBon\fR
1264 Controls whether the file system is shared by using \fBSamba USERSHARES\fR, and what options are to be used. Otherwise, the file system is automatically shared and unshared with the \fBzfs share\fR and \fBzfs unshare\fR commands. If the property is set to \fBon\fR, the \fBnet\fR(8) command is invoked to create a \fBUSERSHARE\fR.
1266 Because \fBSMB\fR shares requires a resource name, a unique resource name is constructed from the dataset name. The constructed name is a copy of the dataset name except that the characters in the dataset name, which would be invalid in the resource name, are replaced with underscore (\fB_\fR) characters. Linux does not currently support additional options which might be available on Solaris.
1268 If the \fBsharesmb\fR property is set to \fBoff\fR, the file systems are unshared.
1270 In Linux, the share is created with the ACL (Access Control List) "Everyone:F" ("F" stands for "full permissions", ie. read and write permissions) and no guest access (which means Samba must be able to authenticate a real user, system passwd/shadow, LDAP or smbpasswd based) by default. This means that any additional access control (disallow specific user specific access etc) must be done on the underlaying filesystem.
1273 Example to mount a SMB filesystem shared through ZFS (share/tmp):
1274 Note that a user and his/her password \fBmust\fR be given!
1277 smbmount //127.0.0.1/share_tmp /mnt/tmp -o user=workgroup/turbo,password=obrut,uid=1000
1283 \fBMinimal /etc/samba/smb.conf configuration\fR
1286 * Samba will need to listen to 'localhost' (127.0.0.1) for the zfs utilities to communicate with Samba. This is the default behavior for most Linux distributions.
1288 * Samba must be able to authenticate a user. This can be done in a number of ways, depending on if using the system password file, LDAP or the Samba specific smbpasswd file. How to do this is outside the scope of this manual. Please refer to the smb.conf(5) manpage for more information.
1290 * See the \fBUSERSHARE\fR section of the \fBsmb.conf\fR(5) man page for all configuration options in case you need to modify any options to the share afterwards. Do note that any changes done with the 'net' command will be undone if the share is every unshared (such as at a reboot etc). In the future, ZoL will be able to set specific options directly using sharesmb=<option>.
1298 \fB\fBsharenfs\fR=\fBoff\fR | \fBon\fR | \fIopts\fR\fR
1302 Controls whether the file system is shared via \fBNFS\fR, and what options are used. A file system with a \fBsharenfs\fR property of \fBoff\fR is managed with the \fBexportfs\fR(8) command and entries in \fB/etc/exports\fR file. Otherwise, the file system is automatically shared and unshared with the \fBzfs share\fR and \fBzfs unshare\fR commands. If the property is set to \fBon\fR, the dataset is shared using the \fBexportfs\fR(8) command in the following manner (see \fBexportfs\fR(8) for the meaning of the different options):
1306 /usr/sbin/exportfs -i -o sec=sys,rw,no_subtree_check,no_root_squash,mountpoint *:<mountpoint of dataset>
1310 Otherwise, the \fBexportfs\fR(8) command is invoked with options equivalent to the contents of this property.
1312 When the \fBsharenfs\fR property is changed for a dataset, the dataset and any children inheriting the property are re-shared with the new options, only if the property was previously \fBoff\fR, or if they were shared before the property was changed. If the new property is \fBoff\fR, the file systems are unshared.
1318 \fB\fBlogbias\fR=\fBlatency\fR | \fBthroughput\fR\fR
1322 Provide a hint to ZFS about handling of synchronous requests in this dataset. If \fBlogbias\fR is set to \fBlatency\fR (the default), ZFS will use pool log devices (if configured) to handle the requests at low latency. If \fBlogbias\fR is set to \fBthroughput\fR, ZFS will not use configured pool log devices. ZFS will instead optimize synchronous operations for global pool throughput and efficient use of resources.
1328 \fB\fBsnapdev\fR=\fBhidden\fR | \fBvisible\fR\fR
1332 Controls whether the snapshots devices of zvol's are hidden or visible. The default value is \fBhidden\fR.
1334 In this context, hidden does not refer to the concept of hiding files or directories by starting their name with a "." character. Even with \fBvisible\fR, the directory is still named \fB\&.zfs\fR. Instead, \fBhidden\fR means that the directory is not returned by \fBreaddir\fR(3), so it doesn't show up in directory listings done by any program, including \fBls\fR \fB-a\fR. It is still possible to chdir(2) into the directory, so \fBcd\fR \fB\&.zfs\fR works even with \fBhidden\fR. This unusual behavior is to protect against unwanted effects from applications recursing into the special \fB\&.zfs\fR directory.
1340 \fB\fBsnapdir\fR=\fBhidden\fR | \fBvisible\fR\fR
1344 Controls whether the \fB\&.zfs\fR directory is hidden or visible in the root of the file system as discussed in the "Snapshots" section. The default value is \fBhidden\fR.
1350 \fB\fBsync\fR=\fBstandard\fR | \fBalways\fR | \fBdisabled\fR\fR
1354 Controls the behavior of synchronous requests (e.g. fsync, O_DSYNC).
1355 \fBstandard\fR is the POSIX specified behavior of ensuring all synchronous
1356 requests are written to stable storage and all devices are flushed to ensure
1357 data is not cached by device controllers (this is the default). \fBalways\fR
1358 causes every file system transaction to be written and flushed before its
1359 system call returns. This has a large performance penalty. \fBdisabled\fR
1360 disables synchronous requests. File system transactions are only committed to
1361 stable storage periodically. This option will give the highest performance.
1362 However, it is very dangerous as ZFS would be ignoring the synchronous
1363 transaction demands of applications such as databases or NFS. Administrators
1364 should only use this option when the risks are understood.
1370 \fB\fBversion\fR=\fB5\fR | \fB4\fR | \fB3\fR | \fB2\fR | \fB1\fR | \fBcurrent\fR\fR
1374 The on-disk version of this file system, which is independent of the pool version. This property can only be set to later supported versions. The value \fBcurrent\fR automatically selects the latest supported version. See the \fBzfs upgrade\fR command.
1380 \fB\fBvolsize\fR=\fIsize\fR\fR
1384 For volumes, specifies the logical size of the volume. By default, creating a volume establishes a \fBrefreservation\fR equal to the volume size plus the metadata required for a fully-written volume. (For pool version 8 or lower, a \fBreservation\fR is set instead.) Any changes to \fBvolsize\fR are reflected in an equivalent change to the \fBrefreservation\fR. The \fBvolsize\fR can only be set to a multiple of \fBvolblocksize\fR, and cannot be zero.
1386 Without the reservation, the volume could run out of space, resulting in undefined behavior or data corruption, depending on how the volume is used. These effects can also occur when the volume size is changed while it is in use (particularly when shrinking the size). Extreme care should be used when adjusting the volume size.
1388 A "sparse volume" (also known as "thin provisioning") can be created by specifying the \fB-s\fR option to the \fBzfs create -V\fR command, or by removing (or changing) the \fBrefreservation\fR after the volume has been created. A "sparse volume" is a volume where the \fBrefreservation\fR is unset or less then the volume size. Consequently, writes to a sparse volume can fail with \fBENOSPC\fR when the pool is low on space. For a sparse volume, changes to \fBvolsize\fR are not reflected in the reservation.
1394 \fB\fBvscan\fR=\fBoff\fR | \fBon\fR\fR
1398 Controls whether regular files should be scanned for viruses when a file is opened and closed. In addition to enabling this property, the virus scan service must also be enabled for virus scanning to occur. The default value is \fBoff\fR.
1400 This property is not used on Linux.
1406 \fB\fBxattr\fR=\fBon\fR | \fBoff\fR | \fBsa\fR\fR
1410 Controls whether extended attributes are enabled for this file system. Two
1411 styles of extended attributes are supported either directory based or system
1414 The default value of \fBon\fR enables directory based extended attributes.
1415 This style of xattr imposes no practical limit on either the size or number of
1416 xattrs which may be set on a file. Although under Linux the \fBgetxattr\fR(2)
1417 and \fBsetxattr\fR(2) system calls limit the maximum xattr size to 64K. This
1418 is the most compatible style of xattr and it is supported by the majority of
1419 ZFS implementations.
1421 System attribute based xattrs may be enabled by setting the value to \fBsa\fR.
1422 The key advantage of this type of xattr is improved performance. Storing
1423 xattrs as system attributes significantly decreases the amount of disk IO
1424 required. Up to 64K of xattr data may be stored per file in the space reserved
1425 for system attributes. If there is not enough space available for an xattr then
1426 it will be automatically written as a directory based xattr. System attribute
1427 based xattrs are not accessible on platforms which do not support the
1428 \fBxattr=sa\fR feature.
1430 The use of system attribute based xattrs is strongly encouraged for users of
1431 SELinux or Posix ACLs. Both of these features heavily rely of xattrs and
1432 benefit significantly from the reduced xattr access time.
1434 The values \fBon\fR and \fBoff\fR are equivalent to the \fBxattr\fR and \fBnoxattr\fR mount options.
1440 \fB\fBzoned\fR=\fBoff\fR | \fBon\fR\fR
1444 Controls whether the dataset is managed from a non-global zone. Zones are a Solaris feature and are not relevant on Linux. The default value is \fBoff\fR.
1449 The following three properties cannot be changed after the file system is created, and therefore, should be set when the file system is created. If the properties are not set with the \fBzfs create\fR or \fBzpool create\fR commands, these properties are inherited from the parent dataset. If the parent dataset lacks these properties due to having been created prior to these features being supported, the new file system will have the default values for these properties.
1453 \fB\fBcasesensitivity\fR=\fBsensitive\fR | \fBinsensitive\fR | \fBmixed\fR\fR
1457 Indicates whether the file name matching algorithm used by the file system should be case-sensitive, case-insensitive, or allow a combination of both styles of matching. The default value for the \fBcasesensitivity\fR property is \fBsensitive\fR. Traditionally, UNIX and POSIX file systems have case-sensitive file names.
1459 The \fBmixed\fR value for the \fBcasesensitivity\fR property indicates that the file system can support requests for both case-sensitive and case-insensitive matching behavior. Currently, case-insensitive matching behavior on a file system that supports mixed behavior is limited to the Solaris CIFS server product.
1465 \fB\fBnormalization\fR = \fBnone\fR | \fBformC\fR | \fBformD\fR | \fBformKC\fR | \fBformKD\fR\fR
1469 Indicates whether the file system should perform a Unicode normalization of file names whenever two file names are compared, and which normalization algorithm should be used.
1471 If this property is set to a value other than \fBnone\fR (the default), and the \fButf8only\fR property was left unspecified, the \fButf8only\fR property is automatically set to \fBon\fR. See the cautionary note in the \fButf8only\fR section before modifying \fBnormalization\fR.
1473 File names are always stored unmodified; names are normalized as part of any comparison process. Thus, \fBformC\fR and \fBformD\fR are equivalent, as are \fBformKC\fR and \fBformKD\fR. Given that, only \fBformD\fR and \fBformKD\fR make sense, as they are slightly faster because they avoid the additional canonical composition step.
1474 .\" unicode.org says it's possible to quickly detect if a string is already in a given form. Since most text (basically everything but OS X) is already in NFC, this means formC could potentially be made faster. But the additional complexity probably isn't worth the likely undetectable in practice speed improvement.
1476 The practical impact of this property is: \fBnone\fR (like traditional filesystems) allows a directory to contain two files that appear (to humans) to have the same name. The other options solve this problem, for different definitions of "the same". If you need to solve this problem and are not sure what to choose,\fBformD\fR.
1478 This property cannot be changed after the file system is created.
1484 \fB\fButf8only\fR=\fBoff\fR | \fBon\fR\fR
1488 Indicates whether the file system should reject file names that include characters that are not present in the \fBUTF-8\fR character set. If this property is explicitly set to \fBoff\fR, the \fBnormalization\fR property must either not be explicitly set or be set to \fBnone\fR. The default value for the \fButf8only\fR property is \fBoff\fR.
1490 Note that forcing the use of \fBUTF-8\fR filenames may cause pain for users. For example, extracting files from an archive will fail if the filenames within the archive are encoded in another character set.
1492 If you are thinking of setting this (to \fBon\fR), you probably want to set \fBnormalization\fR=\fBformD\fR which will set this property to \fBon\fR implicitly.
1494 This property cannot be changed after the file system is created.
1499 The \fBcasesensitivity\fR, \fBnormalization\fR, and \fButf8only\fR properties are also permissions that can be assigned to non-privileged users by using the \fBZFS\fR delegated administration feature.
1505 \fB\fBcontext\fR=\fBnone\fR | \fISELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level\fR\fR
1509 This flag sets the SELinux context for all files in the filesystem under the mountpoint for that filesystem. See \fBselinux\fR(8) for more information.
1515 \fB\fBfscontext\fR=\fBnone\fR | \fISELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level\fR\fR
1519 This flag sets the SELinux context for the filesystem being mounted. See \fBselinux\fR(8) for more information.
1525 \fB\fBdefcontext\fR=\fBnone\fR | \fISELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level\fR\fR
1529 This flag sets the SELinux context for unlabeled files. See \fBselinux\fR(8) for more information.
1535 \fB\fBrootcontext\fR=\fBnone\fR | \fISELinux_User:SElinux_Role:Selinux_Type:Sensitivity_Level\fR\fR
1539 This flag sets the SELinux context for the root inode of the filesystem. See \fBselinux\fR(8) for more information.
1545 \fB\fBoverlay\fR=\fBoff\fR | \fBon\fR\fR
1549 Allow mounting on a busy directory or a directory which already contains files/directories. This is the default mount behavior for Linux filesystems. However, for consistency with ZFS on other platforms overlay mounts are disabled by default. Set \fBoverlay=on\fR to enable overlay mounts.
1552 .SS "Temporary Mount Point Properties"
1554 When a file system is mounted, either through \fBmount\fR(8) for legacy mounts or the \fBzfs mount\fR command for normal file systems, its mount options are set according to its properties. The correlation between properties and mount options is as follows:
1558 PROPERTY MOUNT OPTION
1560 canmount auto/noauto
1561 devices devices/nodevices
1564 relatime relatime/norelatime
1567 nbmand nbmand/nonbmand (Solaris)
1574 In addition, these options can be set on a per-mount basis using the \fB-o\fR option, without affecting the property that is stored on disk. The values specified on the command line override the values stored in the dataset. The \fB-nosuid\fR option is an alias for \fBnodevices,nosetuid\fR. These properties are reported as "temporary" by the \fBzfs get\fR command. If the properties are changed while the dataset is mounted, the new setting overrides any temporary settings.
1575 .SS "User Properties"
1577 In addition to the standard native properties, \fBZFS\fR supports arbitrary user properties. User properties have no effect on \fBZFS\fR behavior, but applications or administrators can use them to annotate datasets (file systems, volumes, and snapshots). Unlike native properties, user properties are editable on snapshots.
1580 User property names must contain a colon (\fB:\fR) character to distinguish them from native properties. They may contain lowercase letters, numbers, and the following punctuation characters: colon (\fB:\fR), dash (\fB-\fR), period (\fB\&.\fR), and underscore (\fB_\fR). The expected convention is that the property name is divided into two portions such as \fImodule\fR\fB:\fR\fIproperty\fR, but this namespace is not enforced by \fBZFS\fR. User property names can be at most 256 characters, and cannot begin with a dash (\fB-\fR).
1583 When making programmatic use of user properties, it is strongly suggested to use a reversed \fBDNS\fR domain name for the \fImodule\fR component of property names to reduce the chance that two independently-developed packages use the same property name for different purposes. For example, property names beginning with \fBcom.sun\fR. are reserved for definition by Oracle Corporation (which acquired Sun Microsystems).
1586 The values of user properties are arbitrary strings, are always inherited, and are never validated. All of the commands that operate on properties (\fBzfs list\fR, \fBzfs get\fR, \fBzfs set\fR, and so forth) can be used to manipulate both native properties and user properties. Use the \fBzfs inherit\fR command to clear a user property. If the property is not defined in any parent dataset, it is removed entirely. Property values are limited to 1024 characters.
1587 .SS "ZFS Volumes as Swap"
1589 \fBZFS\fR volumes may be used as Linux swap devices. After creating the volume
1590 with the \fBzfs create\fR command set up and enable the swap area using the
1591 \fBmkswap\fR(8) and \fBswapon\fR(8) commands. Do not swap to a file on a
1592 \fBZFS\fR file system. A \fBZFS\fR swap file configuration is not supported.
1595 All subcommands that modify state are logged persistently to the pool in their original form. The log can be viewed with \fBzpool history\fR.
1603 Displays a help message.
1609 \fB\fBzfs create\fR [\fB-p\fR] [\fB-o\fR \fIproperty\fR=\fIvalue\fR] ... \fIfilesystem\fR\fR
1613 Creates a new \fBZFS\fR file system. The file system is automatically mounted according to the \fBmountpoint\fR and \fBcanmount\fR properties.
1621 Creates all the non-existing parent datasets. Datasets created in this manner inherit their properties; any property specified on the command line using the \fB-o\fR option applies only to the final child file system. If the target filesystem already exists, the operation completes successfully and no properties are changed.
1627 \fB\fB-o\fR \fIproperty\fR=\fIvalue\fR\fR
1631 Sets the specified property as if the command \fBzfs set\fR \fIproperty\fR=\fIvalue\fR was invoked at the same time the dataset was created. Any editable \fBZFS\fR property can also be set at creation time. Multiple \fB-o\fR options can be specified. An error results if the same property is specified in multiple \fB-o\fR options.
1639 \fB\fBzfs create\fR [\fB-ps\fR] [\fB-b\fR \fIblocksize\fR] [\fB-o\fR \fIproperty\fR=\fIvalue\fR] ... \fB-V\fR \fIsize\fR \fIvolume\fR\fR
1643 Creates a volume of the given size. The volume is exported as a block device in \fB/dev/zvol/\fR\fIpath\fR, where \fIpath\fR is the name of the volume in the \fBZFS\fR namespace. The size represents the logical size as exported by the device. By default, a \fBrefreservation\fR is created.
1645 \fIsize\fR is automatically rounded up to the nearest 128KiB to ensure that the volume has an integral number of blocks regardless of \fIblocksize\fR.
1653 Creates all the non-existing parent datasets as file systems. Datasets created in this manner inherit their properties; any property specified on the command line using the \fB-o\fR option applies only to the final child volume. If the target volume already exists, the operation completes successfully and no properties are changed.
1663 Creates a sparse volume by omitting the automatic creation of a \fBrefreservation\fR. See \fBvolsize\fR in the Native Properties section for more information about sparse volumes. If this option is specified in conjunction with \fB-o\fR \fBrefreservation\fR, the \fBrefreservation\fR will be honored; this allows for a partial reservation on a sparse volume.
1669 \fB\fB-o\fR \fIproperty\fR=\fIvalue\fR\fR
1673 Sets the specified property as if the \fBzfs set\fR \fIproperty\fR=\fIvalue\fR command was invoked at the same time the dataset was created. Any editable \fBZFS\fR property can also be set at creation time. Multiple \fB-o\fR options can be specified. An error results if the same property is specified in multiple \fB-o\fR options.
1675 If \fB-o\fR \fBvolsize\fR is provided, the resulting behavior is undefined; it conflicts with the -V option, which is required in this mode.
1681 \fB\fB-b\fR \fIblocksize\fR\fR
1685 Equivalent to \fB-o\fR \fBvolblocksize\fR=\fIblocksize\fR. If this option is specified in conjunction with \fB-o\fR \fBvolblocksize\fR, the resulting behavior is undefined.
1693 \fBzfs destroy\fR [\fB-fnpRrv\fR] \fIfilesystem\fR|\fIvolume\fR
1697 Destroys the given dataset. By default, the command unshares any file systems that are currently shared, unmounts any file systems that are currently mounted, and refuses to destroy a dataset that has active dependents (children or clones).
1705 Recursively destroy all children.
1715 Recursively destroy all dependents, including cloned file systems outside the target hierarchy.
1725 Force an unmount of any file systems using the \fBzfs unmount -f\fR command. This option has no effect on non-file systems or unmounted file systems.
1735 Do a dry-run ("No-op") deletion. No data will be deleted. This is
1736 useful in conjunction with the \fB-v\fR or \fB-p\fR flags to determine what
1737 data would be deleted.
1747 Print machine-parsable verbose information about the deleted data.
1757 Print verbose information about the deleted data.
1761 Extreme care should be taken when applying either the \fB-r\fR or the \fB-R\fR options, as they can destroy large portions of a pool.
1767 \fBzfs destroy\fR [\fB-dnpRrv\fR] \fIfilesystem\fR|\fIvolume\fR@\fIsnap\fR[%\fIsnap\fR][,...]
1771 The specified snapshots are destroyed immediately if they have no clones and the user-initiated reference count is zero (i.e. there are no holds set with \fBzfs hold\fR). If these conditions are not met, this command returns an error, unless \fB-d\fR is supplied.
1773 An inclusive range of snapshots may be specified by separating the
1774 first and last snapshots with a percent sign.
1775 The first and/or last snapshots may be left blank, in which case the
1776 filesystem's oldest or newest snapshot will be implied.
1779 (or ranges of snapshots) of the same filesystem or volume may be specified
1780 in a comma-separated list of snapshots.
1781 Only the snapshot's short name (the
1782 part after the \fB@\fR) should be specified when using a range or
1783 comma-separated list to identify multiple snapshots.
1791 If a snapshot does not qualify for immediate destruction, rather than returning an error, it is marked for deferred destruction. In this state, it exists as a usable, visible snapshot until both of the preconditions listed above are met, at which point it is destroyed.
1801 Destroy (or mark for deferred destruction) all snapshots with this name in descendent file systems.
1811 Recursively destroy all clones of these snapshots, including the clones,
1812 snapshots, and children. If this flag is specified, the \fB-d\fR flag will
1823 Do a dry-run ("No-op") deletion. No data will be deleted. This is
1824 useful in conjunction with the \fB-v\fR or \fB-p\fR flags to determine what
1825 data would be deleted.
1835 Print machine-parsable verbose information about the deleted data.
1845 Print verbose information about the deleted data.
1849 Extreme care should be taken when applying either the \fB-r\fR or the \fB-R\fR
1850 options, as they can destroy large portions of a pool and cause unexpected
1851 behavior for mounted file systems in use.
1859 \fBzfs destroy\fR \fIfilesystem\fR|\fIvolume\fR#\fIbookmark\fR
1863 The given bookmark is destroyed.
1870 \fB\fBzfs snapshot\fR [\fB-r\fR] [\fB-o\fR \fIproperty\fR=\fIvalue\fR] ... \fIfilesystem@snapname\fR|\fIvolume@snapname\fR\fR ...
1874 Creates snapshots with the given names. All previous modifications by successful system calls to the file system are part of the snapshots. Snapshots are taken atomically, so that all snapshots correspond to the same moment in time. See the "Snapshots" section for details.
1882 Recursively create snapshots of all descendent datasets.
1888 \fB\fB-o\fR \fIproperty\fR=\fIvalue\fR\fR
1892 Sets the specified property; see \fBzfs set\fR for details.
1900 \fB\fBzfs rollback\fR [\fB-rRf\fR] \fIsnapshot\fR\fR
1904 Roll back the given dataset to a previous snapshot. When a dataset is rolled back, all data that has changed since the snapshot is discarded, and the dataset reverts to the state at the time of the snapshot. By default, the command refuses to roll back to a snapshot other than the most recent one. In order to do so, all intermediate snapshots and bookmarks must be destroyed by specifying the \fB-r\fR option.
1906 The \fB-rR\fR options do not recursively destroy the child snapshots of a recursive snapshot. Only direct snapshots of the specified filesystem are destroyed by either of these options. To completely roll back a recursive snapshot, you must rollback the individual child snapshots.
1914 Destroy any snapshots and bookmarks more recent than the one specified.
1924 Recursively destroy any more recent snapshots and bookmarks, as well as any clones of those snapshots.
1934 Used with the \fB-R\fR option to force an unmount (see \fBzfs unmount -f\fR) of any clone file systems that are to be destroyed.
1942 \fB\fBzfs clone\fR [\fB-p\fR] [\fB-o\fR \fIproperty\fR=\fIvalue\fR] ... \fIsnapshot\fR \fIfilesystem\fR|\fIvolume\fR\fR
1946 Creates a clone of the given snapshot. See the "Clones" section for details. The target dataset can be located anywhere in the \fBZFS\fR hierarchy, and is created as the same type as the original.
1954 Creates all the non-existing parent datasets; see \fBzfs create\fR for details.
1960 \fB\fB-o\fR \fIproperty\fR=\fIvalue\fR\fR
1964 Sets the specified property; see \fBzfs set\fR for details.
1972 \fB\fBzfs promote\fR \fIclone-filesystem\fR\fR
1976 Promotes a clone file system to no longer be dependent on its "origin" snapshot. This makes it possible to destroy the file system that the clone was created from. The clone parent-child dependency relationship is reversed, so that the origin file system becomes a clone of the specified file system.
1978 The snapshot that was cloned, and any snapshots previous to this snapshot, are now owned by the promoted clone. The space they use moves from the origin file system to the promoted clone, so enough space must be available to accommodate these snapshots. No new space is consumed by this operation, but the space accounting is adjusted. The promoted clone must not have any conflicting snapshot names of its own. The \fBzfs rename\fR command can be used to rename any conflicting snapshots.
1984 \fB\fBzfs rename\fR [\fB-f\fR] \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR\fR
1988 \fB\fBzfs rename\fR [\fB-fp\fR] \fIfilesystem\fR|\fIvolume\fR \fIfilesystem\fR|\fIvolume\fR\fR
1992 Renames the given dataset. The new target can be located anywhere in the \fBZFS\fR hierarchy, with the exception of snapshots. Snapshots can only be renamed within the parent file system or volume. When renaming a snapshot, the parent file system of the snapshot does not need to be specified as part of the second argument. Renamed file systems can inherit new mount points, in which case they are unmounted and remounted at the new mount point.
2000 Creates all the nonexistent parent datasets; see \fBzfs create\fR for details.
2010 Force unmount any filesystems that need to be unmounted in the process.
2018 \fB\fBzfs rename\fR \fB-r\fR \fIsnapshot\fR \fIsnapshot\fR\fR
2022 Recursively rename the snapshots of all descendent datasets. Snapshots are the only dataset that can be renamed recursively.
2028 \fB\fBzfs\fR \fBlist\fR [\fB-r\fR|\fB-d\fR \fIdepth\fR] [\fB-Hp\fR] [\fB-o\fR \fIproperty\fR[,\fI\&...\fR]] [ \fB-t\fR \fItype\fR[,\fI\&...\fR]] [ \fB-s\fR \fIproperty\fR ] ... [ \fB-S\fR \fIproperty\fR ] ... [\fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR|\fImountpoint\fR] ...\fR
2032 Lists the property information for the given datasets in tabular form. If a mount point is specified, it can be an absolute pathname or a relative pathname starting with "./" (e.g. \fBzfs list ./\fR). By default, all file systems and volumes are displayed. Snapshots are displayed if the pool's \fBlistsnapshots\fR property is \fBon\fR (the default is \fBoff\fR). When listing hundreds or thousands of snapshots performance can be improved by restricting the output to only the name. In that case, it is recommended to use \fB-o name -s name\fR. The following fields are displayed by default: \fBname, used, available, referenced, mountpoint\fR
2040 Used for scripting mode. Do not print headers and separate fields by a single tab instead of arbitrary white space.
2049 Display numbers in parsable (exact) values.
2059 Recursively display any children of the dataset on the command line.
2065 \fB\fB-d\fR \fIdepth\fR\fR
2069 Recursively display any children of the dataset, limiting the recursion to \fIdepth\fR. A depth of \fB1\fR will display only the dataset and its direct children.
2075 \fB\fB-o\fR \fIproperty\fR\fR
2079 A comma-separated list of properties to display. The property must be:
2084 One of the properties described in the "Native Properties" section
2096 The value \fBname\fR to display the dataset name
2102 The value \fBspace\fR to display space usage properties on file systems and volumes. This is a shortcut for specifying \fB-o name,avail,used,usedsnap,usedds,usedrefreserv,usedchild\fR \fB-t filesystem,volume\fR syntax.
2109 \fB\fB-s\fR \fIproperty\fR\fR
2113 A property for sorting the output by column in ascending order based on the value of the property. The property must be one of the properties described in the "Properties" section, or the special value \fBname\fR to sort by the dataset name. Multiple properties can be specified at one time using multiple \fB-s\fR property options. Multiple \fB-s\fR options are evaluated from left to right in decreasing order of importance.
2115 The following is a list of sorting criteria:
2120 Numeric types sort in numeric order.
2126 String types sort in alphabetical order.
2132 Types inappropriate for a row sort that row to the literal bottom, regardless of the specified ordering.
2138 If no sorting options are specified the existing behavior of \fBzfs list\fR is preserved.
2145 \fB\fB-S\fR \fIproperty\fR\fR
2149 Same as the \fB-s\fR option, but sorts by property in descending order.
2155 \fB\fB-t\fR \fItype\fR\fR
2159 A comma-separated list of types to display, where \fItype\fR is one of \fBfilesystem\fR, \fBsnapshot\fR, \fBsnap\fR, \fBvolume\fR, \fBbookmark\fR, or \fBall\fR. For example, specifying \fB-t snapshot\fR displays only snapshots.
2167 \fB\fBzfs set\fR \fIproperty\fR=\fIvalue\fR[ \fIproperty\fR=\fIvalue\fR]...
2168 \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR ...\fR
2172 Sets the property or list of properties to the given value(s) for each dataset.
2173 Only some properties can be edited. See the "Properties" section for more
2174 information on which properties can be set and acceptable values. User properties
2175 can be set on snapshots. For more information, see the "User Properties" section.
2180 \fB\fBzfs get\fR [\fB-r\fR|\fB-d\fR \fIdepth\fR] [\fB-Hp\fR] [\fB-o\fR \fIfield\fR[,...] [\fB-t\fR \fItype\fR[,...]] [\fB-s\fR \fIsource\fR[,...] "\fIall\fR" | \fIproperty\fR[,...] \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR ...\fR
2184 Displays properties for the given datasets. If no datasets are specified, then the command displays properties for all datasets on the system. For each property, the following columns are displayed:
2189 property Property name
2190 value Property value
2191 source Property source. Can either be local, default,
2192 temporary, inherited, received, or none (-).
2197 All columns are displayed by default, though this can be controlled by using the \fB-o\fR option. This command takes a comma-separated list of properties as described in the "Native Properties" and "User Properties" sections.
2199 The special value \fBall\fR can be used to display all properties that apply to the given dataset's type (filesystem, volume snapshot, or bookmark).
2207 Recursively display properties for any children.
2213 \fB\fB-d\fR \fIdepth\fR\fR
2217 Recursively display any children of the dataset, limiting the recursion to \fIdepth\fR. A depth of \fB1\fR will display only the dataset and its direct children.
2227 Display output in a form more easily parsed by scripts. Any headers are omitted, and fields are explicitly separated by a single tab instead of an arbitrary amount of space.
2233 \fB\fB-o\fR \fIfield\fR\fR
2237 A comma-separated list of columns to display. \fBname,property,value,source\fR is the default value.
2243 \fB\fB-s\fR \fIsource\fR\fR
2247 A comma-separated list of sources to display. Those properties coming from a source other than those in this list are ignored. Each source must be one of the following: \fBlocal,default,inherited,received,temporary,none\fR. The default value is all sources.
2257 Display numbers in parsable (exact) values.
2265 \fB\fBzfs inherit\fR [\fB-rS\fR] \fIproperty\fR \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR ...\fR
2269 Clears the specified property, causing it to be inherited from an ancestor, restored to default if no ancestor has the property set, or with the \fB-S\fR option reverted to the received value if one exists. See the "Properties" section for a listing of default values, and details on which properties can be inherited.
2277 Recursively inherit the given property for all children.
2286 Revert the property to the received value if one exists; otherwise operate as
2287 if the \fB-S\fR option was not specified.
2295 \fB\fBzfs upgrade\fR
2299 Displays a list of file systems that are not the most recent version.
2305 \fB\fBzfs upgrade\fR \fB-v\fR\fR
2309 Displays a list of file system versions.
2316 \fB\fBzfs upgrade\fR [\fB-r\fR] [\fB-V\fR \fIversion\fR] [\fB-a\fR | \fIfilesystem\fR]\fR
2320 Upgrades file systems to a new on-disk version. Once this is done, the file systems will no longer be accessible on systems running older versions of the software. \fBzfs send\fR streams generated from new snapshots of these file systems cannot be accessed on systems running older versions of the software.
2322 In general, the file system version is independent of the pool version. See \fBzpool\fR(8) for information on the \fBzpool upgrade\fR command.
2324 In some cases, the file system version and the pool version are interrelated and the pool version must be upgraded before the file system version can be upgraded.
2332 Upgrades all file systems on all imported pools.
2338 \fB\fIfilesystem\fR\fR
2342 Upgrades the specified file system.
2352 Upgrades the specified file system and all descendent file systems
2358 \fB\fB-V\fR \fIversion\fR\fR
2362 Upgrades to the specified \fIversion\fR. If the \fB-V\fR flag is not specified, this command upgrades to the most recent version. This option can only be used to increase the version number, and only up to the most recent version supported by this software.
2370 \fBzfs\fR \fBuserspace\fR [\fB-Hinp\fR] [\fB-o\fR \fIfield\fR[,...]]
2371 [\fB-s\fR \fIfield\fR] ...
2372 [\fB-S\fR \fIfield\fR] ...
2373 [\fB-t\fR \fItype\fR[,...]] \fIfilesystem\fR|\fIsnapshot\fR
2377 Displays space consumed by, and quotas on, each user in the specified
2378 filesystem or snapshot. This corresponds to the \fBuserused@\fR\fIuser\fR and
2379 \fBuserquota@\fR\fIuser\fR properties.
2387 Print numeric ID instead of user/group name.
2397 Display output in a form more easily parsed by scripts. Any headers are omitted, and fields are explicitly separated by a single tab instead of an arbitrary amount of space.
2407 Use exact (parsable) numeric output.
2413 \fB\fB-o\fR \fIfield\fR[,...]\fR
2417 Display only the specified fields from the following
2418 set: \fBtype, name, used, quota\fR. The default is to display all fields.
2424 \fB\fB-s\fR \fIfield\fR\fR
2428 Sort output by this field. The \fIs\fR and \fIS\fR flags may be specified
2429 multiple times to sort first by one field, then by another. The default is
2430 \fB-s type\fR \fB-s name\fR.
2436 \fB\fB-S\fR \fIfield\fR\fR
2440 Sort by this field in reverse order. See \fB-s\fR.
2446 \fB\fB-t\fR \fItype\fR[,...]\fR
2450 Print only the specified types from the following
2451 set: \fBall, posixuser, smbuser, posixgroup, smbgroup\fR. The default
2452 is \fB-t posixuser,smbuser\fR. The default can be changed to include group
2463 Translate SID to POSIX ID. The POSIX ID may be ephemeral if no mapping exists.
2464 Normal POSIX interfaces (for example, \fBstat\fR(2), \fBls\fR(1) \fB-l\fR) perform
2465 this translation, so the \fB-i\fR option allows the output from \fBzfs
2466 userspace\fR to be compared directly with those utilities. However, \fB-i\fR
2467 may lead to confusion if some files were created by an SMB user before a
2468 SMB-to-POSIX name mapping was established. In such a case, some files will be owned
2469 by the SMB entity and some by the POSIX entity. However, the \fB-i\fR option
2470 will report that the POSIX entity has the total usage and quota for both.
2472 This option is not useful on Linux.
2480 \fBzfs\fR \fBgroupspace\fR [\fB-Hinp\fR] [\fB-o\fR \fIfield\fR[,...]]
2481 [\fB-s\fR \fIfield\fR] ...
2482 [\fB-S\fR \fIfield\fR] ...
2483 [\fB-t\fR \fItype\fR[,...]] \fIfilesystem\fR|\fIsnapshot\fR
2487 Displays space consumed by, and quotas on, each group in the specified
2488 filesystem or snapshot. This subcommand is identical to \fBzfs userspace\fR,
2489 except that the default types to display are \fB-t posixgroup,smbgroup\fR.
2495 \fB\fBzfs mount\fR\fR
2499 Displays all \fBZFS\fR file systems currently mounted.
2505 \fB\fBzfs mount\fR [\fB-vO\fR] [\fB-o\fR \fIoptions\fR] \fB-a\fR | \fIfilesystem\fR\fR
2509 Mounts \fBZFS\fR file systems. This is invoked automatically as part of the boot process.
2513 \fB\fB-o\fR \fIoptions\fR\fR
2517 An optional, comma-separated list of mount options to use temporarily for the
2518 duration of the mount. See the "Temporary Mount Point Properties" section for
2529 Allow mounting the filesystem even if the target directory is not empty.
2531 On Solaris, the behavior of \fBzfs mount\fR matches \fBmount\fR and \fBzfs mount -O\fR matches \fBmount -O\fR. See \fBmount\fR(1M).
2533 On Linux, this is the default for \fBmount\fR(8). In other words, \fBzfs mount -O\fR matches \fBmount\fR and there is no \fBmount\fR equivalent to a plain \fBzfs mount\fR.
2543 Report mount progress. This is intended for use with \fBzfs mount -a\fR on a system with a significant number of filesystems.
2553 Mount all available \fBZFS\fR file systems. Invoked automatically as part of
2560 \fB\fIfilesystem\fR\fR
2564 Mount the specified filesystem.
2572 \fB\fBzfs unmount\fR [\fB-f\fR] \fB-a\fR | \fIfilesystem\fR|\fImountpoint\fR\fR
2576 Unmounts currently mounted \fBZFS\fR file systems. Invoked automatically as part of the shutdown process.
2584 Forcefully unmount the file system, even if it is currently in use.
2594 Unmount all available \fBZFS\fR file systems. Invoked automatically as part of the shutdown process.
2600 \fIfilesystem\fR|\fImountpoint\fR
2604 Unmount the specified filesystem. The command can also be given a path to a \fBZFS\fR file system mount point on the system.
2612 \fB\fBzfs share\fR \fB-a\fR | \fIfilesystem\fR\fR
2616 Shares available \fBZFS\fR file systems.
2624 Share all available \fBZFS\fR file systems. Invoked automatically as part of the boot process.
2630 \fB\fIfilesystem\fR\fR
2634 Share the specified filesystem according to the \fBsharenfs\fR and \fBsharesmb\fR properties. File systems are shared when the \fBsharenfs\fR or \fBsharesmb\fR property is set.
2642 \fB\fBzfs unshare\fR \fB-a\fR | \fIfilesystem\fR|\fImountpoint\fR\fR
2646 Unshares currently shared \fBZFS\fR file systems. This is invoked automatically as part of the shutdown process.
2654 Unshare all available \fBZFS\fR file systems. Invoked automatically as part of the boot process.
2660 \fB\fIfilesystem\fR|\fImountpoint\fR\fR
2664 Unshare the specified filesystem. The command can also be given a path to a \fBZFS\fR file system shared on the system.
2672 \fB\fBzfs bookmark\fR \fIsnapshot\fR \fIbookmark\fR\fR
2676 Creates a bookmark of the given snapshot. Bookmarks mark the point in time
2677 when the snapshot was created, and can be used as the incremental source for
2678 a \fBzfs send\fR command.
2680 This feature must be enabled to be used.
2681 See \fBzpool-features\fR(5) for details on ZFS feature flags and the
2682 \fBbookmarks\fR feature.
2690 \fBzfs send\fR [\fB-DnPpRveLc\fR] [\fB-\fR[\fBiI\fR] \fIsnapshot\fR] \fIsnapshot\fR
2694 Creates a stream representation of the (second, if \fB-i\fR is specified) \fIsnapshot\fR, which is written to standard output. The output can be redirected to a file or to a pipe (for example, using \fBssh\fR(1) to send it to a different system with \fBzfs receive\fR). By default, a full stream is generated; specifying \fB-i\fR or \fB-I\fR changes this behavior.
2698 \fB\fB-i\fR \fIsnapshot\fR\fR
2702 Generate an incremental stream from the first \fIsnapshot\fR (the incremental source) to the second \fIsnapshot\fR (the incremental target). The incremental source can be specified as the last component of the snapshot name (the \fB@\fR character and following) and it is assumed to be from the same file system as the incremental target.
2704 If the destination is a clone, the source may be the origin snapshot, which must be fully specified (for example, \fBpool/fs@origin\fR, not just \fB@origin\fR).
2710 \fB\fB-I\fR \fIsnapshot\fR\fR
2714 Generate a stream package that sends all intermediary snapshots from the first snapshot to the second snapshot. For example, \fB-I @a fs@d\fR is similar to \fB-i @a fs@b; -i @b fs@c; -i @c fs@d\fR. The incremental source may be specified as with the \fB-i\fR option.
2724 Generate a replication stream package, which will replicate the specified filesystem, and all descendent file systems, up to the named snapshot. When received, all properties, snapshots, descendent file systems, and clones are preserved.
2726 If the \fB-i\fR or \fB-I\fR flags are used in conjunction with the \fB-R\fR flag, an incremental replication stream is generated. The current values of properties, and current snapshot and file system names are set when the stream is received. If the \fB-F\fR flag is specified when this stream is received, snapshots and file systems that do not exist on the sending side are destroyed.
2736 Generate a deduplicated stream. Blocks which would have been sent multiple times in the send stream will only be sent once. The receiving system must also support this feature to receive a deduplicated stream. This flag can be used regardless of the dataset's dedup property, but performance will be much better if the filesystem uses a dedup-capable checksum (eg. sha256).
2746 Generate a stream which may contain blocks larger than 128KiB. This flag
2747 has no effect if the \fBlarge_blocks\fR pool feature is disabled, or if
2748 the \fRrecordsize\fR property of this filesystem has never been set above
2749 128KiB. The receiving system must have the \fBlarge_blocks\fR pool feature
2750 enabled as well. See \fBzpool-features\fR(5) for details on ZFS feature
2751 flags and the \fBlarge_blocks\fR feature.
2761 Generate a more compact stream by using WRITE_EMBEDDED records for blocks
2762 which are stored more compactly on disk by the \fBembedded_data\fR pool
2763 feature. This flag has no effect if the \fBembedded_data\fR feature is
2764 disabled. The receiving system must have the \fBembedded_data\fR feature
2765 enabled. If the \fBlz4_compress\fR feature is active on the sending system,
2766 then the receiving system must have that feature enabled as well. See
2767 \fBzpool-features\fR(5) for details on ZFS feature flags and the
2768 \fBembedded_data\fR feature.
2774 \fB\fB-c\fR, \fB--compressed\fR\fR
2778 Generate a more compact stream by using compressed WRITE records for blocks
2779 which are compressed on disk and in memory (see the \fBcompression\fR property
2780 for details). If the \fBlz4_compress\fR feature is active on the sending
2781 system, then the receiving system must have that feature enabled as well. If
2782 the \fBlarge_blocks\fR feature is enabled on the sending system but the \fB-L\fR
2783 option is not supplied in conjunction with \fB-c\fR, then the data will be
2784 decompressed before sending so it can be split into smaller block sizes.
2794 Include the dataset's properties in the stream. This flag is implicit when -R is specified. The receiving system must also support this feature.
2804 Do a dry-run ("No-op") send. Do not generate any actual send data. This is
2805 useful in conjunction with the \fB-v\fR or \fB-P\fR flags to determine what
2806 data will be sent. In this case, the verbose output will be written to
2807 standard output (contrast with a non-dry-run, where the stream is written
2808 to standard output and the verbose output goes to standard error).
2818 Print machine-parsable verbose information about the stream package generated.
2828 Print verbose information about the stream package generated. This information
2829 includes a per-second report of how much data has been sent.
2832 The format of the stream is committed. You will be able to receive your streams on future versions of \fBZFS\fR.
2839 \fBzfs send\fR [\fB-Lec\fR] [\fB-i\fR \fIsnapshot\fR|\fIbookmark\fR] \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR
2843 Generate a send stream, which may be of a filesystem, and may be
2844 incremental from a bookmark. If the destination is a filesystem or volume,
2845 the pool must be read-only, or the filesystem must not be mounted. When the
2846 stream generated from a filesystem or volume is received, the default snapshot
2847 name will be "--head--".
2856 Generate a stream which may contain blocks larger than 128KiB. This flag
2857 has no effect if the \fBlarge_blocks\fR pool feature is disabled, or if
2858 the \fRrecordsize\fR property of this filesystem has never been set above
2859 128KiB. The receiving system must have the \fBlarge_blocks\fR pool feature
2860 enabled as well. See \fBzpool-features\fR(5) for details on ZFS feature
2861 flags and the \fBlarge_blocks\fR feature.
2871 Generate a more compact stream by using WRITE_EMBEDDED records for blocks
2872 which are stored more compactly on disk by the \fBembedded_data\fR pool
2873 feature. This flag has no effect if the \fBembedded_data\fR feature is
2874 disabled. The receiving system must have the \fBembedded_data\fR feature
2875 enabled. If the \fBlz4_compress\fR feature is active on the sending system,
2876 then the receiving system must have that feature enabled as well. See
2877 \fBzpool-features\fR(5) for details on ZFS feature flags and the
2878 \fBembedded_data\fR feature.
2884 \fB\fB-c\fR, \fB--compressed\fR\fR
2888 Generate a more compact stream by using compressed WRITE records for blocks
2889 which are compressed on disk and in memory (see the \fBcompression\fR property
2890 for details). If the \fBlz4_compress\fR feature is active on the sending
2891 system, then the receiving system must have that feature enabled as well. If
2892 the \fBlarge_blocks\fR feature is enabled on the sending system but the \fB-L\fR
2893 option is not supplied in conjunction with \fB-c\fR, then the data will be
2894 decompressed before sending so it can be split into smaller block sizes.
2900 \fB-i\fR \fIsnapshot\fR|\fIbookmark\fR
2904 Generate an incremental send stream. The incremental source must be an earlier snapshot in the destination's history. It will commonly be an earlier snapshot in the destination's filesystem, in which case it can be specified as the last component of the name (the \fB#\fR or \fB@\fR character and following).
2906 If the incremental target is a clone, the incremental source can be the origin snapshot, or an earlier snapshot in the origin's filesystem, or the origin's origin, etc.
2913 \fB\fBzfs send\fR [\fB-Penv\fR] \fB-t\fR \fIreceive_resume_token\fR\fR
2917 Creates a send stream which resumes an interrupted receive. The \fIreceive_resume_token\fR is the value of this property on the filesystem or volume that was being received into. See the documentation for \fBzfs receive -s\fR for more details.
2925 \fB\fBzfs receive\fR [\fB-Fnsuv\fR] [\fB-o origin\fR=\fIsnapshot\fR] \fIfilesystem\fR|\fIvolume\fR|\fIsnapshot\fR\fR
2929 \fB\fBzfs receive\fR [\fB-Fnsuv\fR] [\fB-d\fR|\fB-e\fR] [\fB-o origin\fR=\fIsnapshot\fR] \fIfilesystem\fR\fR
2933 Creates a snapshot whose contents are as specified in the stream provided on standard input. If a full stream is received, then a new file system is created as well. Streams are created using the \fBzfs send\fR subcommand, which by default creates a full stream. \fBzfs recv\fR can be used as an alias for \fBzfs receive\fR.
2935 If an incremental stream is received, then the destination file system must already exist, and its most recent snapshot must match the incremental stream's source. For \fBzvols\fR, the destination device link is destroyed and recreated, which means the \fBzvol\fR cannot be accessed during the \fBreceive\fR operation.
2937 When a snapshot replication package stream that is generated by using the \fBzfs send\fR \fB-R\fR command is received, any snapshots that do not exist on the sending location are destroyed by using the \fBzfs destroy\fR \fB-d\fR command.
2939 The name of the snapshot (and file system, if a full stream is received) that this subcommand creates depends on the argument type and the use of the \fB-d\fR or \fB-e\fR options.
2941 If the argument is a snapshot name, the specified \fIsnapshot\fR is created. If the argument is a file system or volume name, a snapshot with the same name as the sent snapshot is created within the specified \fIfilesystem\fR or \fIvolume\fR. If neither of the \fB-d\fR or \fB-e\fR options are specified, the provided target snapshot name is used exactly as provided.
2943 The \fB-d\fR and \fB-e\fR options cause the file system name of the target snapshot to be determined by appending a portion of the sent snapshot's name to the specified target \fIfilesystem\fR. If the \fB-d\fR option is specified, all but the first element of the sent snapshot's file system path (usually the pool name) is used and any required intermediate file systems within the specified one are created. If the \fB-e\fR option is specified, then only the last element of the sent snapshot's file system name (i.e. the name of the source file system itself) is used as the target file system name.
2951 Force a rollback of the file system to the most recent snapshot before performing the receive operation. If receiving an incremental replication stream (for example, one generated by \fBzfs send -R -[iI]\fR), destroy snapshots and file systems that do not exist on the sending side.
2962 Do not actually receive the stream. This can be useful in conjunction with the \fB-v\fR option to verify the name the receive operation would use.
2972 If the receive is interrupted, save the partially received state, rather than deleting it. Interruption may be due to premature termination of the stream (e.g. due to network failure or failure of the remote system if the stream is being read over a network connection), a checksum error in the stream, termination of the \fBzfs receive\fR process, or unclean shutdown of the system.
2974 The receive can be resumed with a stream generated by \fBzfs send -t\fR token, where the \fItoken\fR is the value of the \fBreceive_resume_token\fR property of the filesystem or volume which is received into.
2976 To use this flag, the storage pool must have the \fBextensible_dataset\fR feature enabled. See \fBzpool-features\fR(5) for details on ZFS feature flags.
2986 Do not mount the file system that is associated with the received stream.
2996 Print verbose information about the stream and the time required to perform the receive operation.
3006 Discard the first element of the sent snapshot's file system name, using the remaining elements to determine the name of the target file system for the new snapshot as described in the paragraph above.
3016 Discard all but the last element of the sent snapshot's file system name, using that element to determine the name of the target file system for the new snapshot as described in the paragraph above.
3022 \fB\fB-o\fR \fBorigin\fR=\fIsnapshot\fR
3026 Forces the stream to be received as a clone of the given snapshot.
3027 If the stream is a full send stream, this will create the filesystem
3028 described by the stream as a clone of the specified snapshot. Which
3029 snapshot was specified will not affect the success or failure of the
3030 receive, as long as the snapshot does exist. If the stream is an
3031 incremental send stream, all the normal verification will be performed.
3039 \fB\fBzfs receive\fR [\fB-A\fR] \fIfilesystem\fR|\fIvolume\fR
3043 Abort an interrupted \fBzfs receive \fB-s\fR\fR, deleting its saved partially received state.
3050 \fB\fBzfs allow\fR \fIfilesystem\fR | \fIvolume\fR\fR
3054 Displays permissions that have been delegated on the specified filesystem or volume. See the other forms of \fBzfs allow\fR for more information.
3056 Delegations are supported under Linux with the exception of \fBmount\fR,
3057 \fBunmount\fR, \fBmountpoint\fR, \fBcanmount\fR, \fBrename\fR, and \fBshare\fR.
3058 These permissions cannot be delegated because the Linux \fBmount(8)\fR command
3059 restricts modifications of the global namespace to the root user.
3065 \fB\fBzfs allow\fR [\fB-ldug\fR] "\fIeveryone\fR"|\fIuser\fR|\fIgroup\fR[,...] \fIperm\fR|@\fIsetname\fR[,...] \fIfilesystem\fR| \fIvolume\fR\fR
3069 \fB\fBzfs allow\fR [\fB-ld\fR] \fB-e\fR \fIperm\fR|@\fIsetname\fR[,...] \fIfilesystem\fR | \fIvolume\fR\fR
3073 Delegates \fBZFS\fR administration permission for the file systems to non-privileged users.
3077 \fB[\fB-ug\fR] "\fIeveryone\fR"|\fIuser\fR|\fIgroup\fR[,...]\fR
3081 Specifies to whom the permissions are delegated. Multiple entities can be specified as a comma-separated list. If neither of the \fB-ug\fR options are specified, then the argument is interpreted preferentially as the keyword "everyone", then as a user name, and lastly as a group name. To specify a user or group named "everyone", use the \fB-u\fR or \fB-g\fR options. To specify a group with the same name as a user, use the \fB-g\fR options.
3087 \fB[\fB-e\fR] \fIperm\fR|@\fIsetname\fR[,...]\fR
3091 Specifies that the permissions be delegated to "everyone." Multiple permissions may be specified as a comma-separated list. Permission names are the same as \fBZFS\fR subcommand and property names. See the property list below. Property set names, which begin with an at sign (\fB@\fR) , may be specified. See the \fB-s\fR form below for details.
3097 \fB[\fB-ld\fR] \fIfilesystem\fR|\fIvolume\fR\fR
3101 Specifies where the permissions are delegated. If neither of the \fB-ld\fR options are specified, or both are, then the permissions are allowed for the file system or volume, and all of its descendents. If only the \fB-l\fR option is used, then is allowed "locally" only for the specified file system. If only the \fB-d\fR option is used, then is allowed only for the descendent file systems.
3108 Permissions are generally the ability to use a \fBzfs\fR subcommand or change a property. The following permissions are available:
3113 allow subcommand Must also have the permission that is being
3115 clone subcommand Must also have the 'create' ability and 'mount'
3116 ability in the origin file system
3117 create subcommand Must also have the 'mount' ability
3118 destroy subcommand Must also have the 'mount' ability
3119 diff subcommand Allows lookup of paths within a dataset
3120 given an object number, and the ability to
3121 create snapshots necessary to 'zfs diff'.
3122 mount subcommand Allows mount/umount of ZFS datasets
3123 promote subcommand Must also have the 'mount'
3124 and 'promote' ability in the origin file system
3125 receive subcommand Must also have the 'mount' and 'create' ability
3126 rename subcommand Must also have the 'mount' and 'create'
3127 ability in the new parent
3128 rollback subcommand Must also have the 'mount' ability
3130 share subcommand Allows sharing file systems over NFS or SMB
3132 snapshot subcommand Must also have the 'mount' ability
3133 groupquota other Allows accessing any groupquota@... property
3134 groupused other Allows reading any groupused@... property
3135 userprop other Allows changing any user property
3136 userquota other Allows accessing any userquota@... property
3137 userused other Allows reading any userused@... property
3143 casesensitivity property
3145 compression property
3150 filesystem_limit property
3155 normalization property
3156 primarycache property
3161 refreservation property
3162 reservation property
3163 secondarycache property
3168 snapshot_limit property
3171 volblocksize property
3183 \fB\fBzfs allow\fR \fB-c\fR \fIperm\fR|@\fIsetname\fR[,...] \fIfilesystem\fR|\fIvolume\fR\fR
3187 Sets "create time" permissions. These permissions are granted (locally) to the creator of any newly-created descendent file system.
3193 \fB\fBzfs allow\fR \fB-s\fR @\fIsetname\fR \fIperm\fR|@\fIsetname\fR[,...] \fIfilesystem\fR|\fIvolume\fR\fR
3197 Defines or adds permissions to a permission set. The set can be used by other \fBzfs allow\fR commands for the specified file system and its descendents. Sets are evaluated dynamically, so changes to a set are immediately reflected. Permission sets follow the same naming restrictions as ZFS file systems, but the name must begin with an "at sign" (\fB@\fR), and can be no more than 64 characters long.
3203 \fB\fBzfs unallow\fR [\fB-rldug\fR] "\fIeveryone\fR"|\fIuser\fR|\fIgroup\fR[,...] [\fIperm\fR|@\fIsetname\fR[, ...]] \fIfilesystem\fR|\fIvolume\fR\fR
3207 \fB\fBzfs unallow\fR [\fB-rld\fR] \fB-e\fR [\fIperm\fR|@\fIsetname\fR [,...]] \fIfilesystem\fR|\fIvolume\fR\fR
3211 \fB\fBzfs unallow\fR [\fB-r\fR] \fB-c\fR [\fIperm\fR|@\fIsetname\fR[,...]]\fR \fB\fIfilesystem\fR|\fIvolume\fR\fR
3215 Removes permissions that were granted with the \fBzfs allow\fR command. No permissions are explicitly denied, so other permissions granted are still in effect. For example, if the permission is granted by an ancestor. If no permissions are specified, then all permissions for the specified \fIuser\fR, \fIgroup\fR, or \fIeveryone\fR are removed. Specifying "everyone" (or using the \fB-e\fR option) only removes the permissions that were granted to "everyone", not all permissions for every user and group. See the \fBzfs allow\fR command for a description of the \fB-ldugec\fR options.
3223 Recursively remove the permissions from this file system and all descendents.
3231 \fB\fBzfs unallow\fR [\fB-r\fR] \fB-s\fR @\fIsetname\fR [\fIperm\fR|@\fIsetname\fR[,...]]\fR \fB\fIfilesystem\fR|\fIvolume\fR\fR
3235 Removes permissions from a permission set. If no permissions are specified, then all permissions are removed, thus removing the set entirely.
3241 \fB\fBzfs hold\fR [\fB-r\fR] \fItag\fR \fIsnapshot\fR...\fR
3245 Adds a single reference, named with the \fItag\fR argument, to the specified snapshot or snapshots. Each snapshot has its own tag namespace, and tags must be unique within that space.
3247 If a hold exists on a snapshot, attempts to destroy that snapshot by using the \fBzfs destroy\fR command return \fBEBUSY\fR.
3255 Specifies that a hold with the given tag is applied recursively to the snapshots of all descendent file systems.
3263 \fB\fBzfs holds\fR [\fB-r\fR] \fIsnapshot\fR...\fR
3267 Lists all existing user references for the given snapshot or snapshots.
3275 Lists the holds that are set on the named descendent snapshots, in addition to listing the holds on the named snapshot.
3283 \fB\fBzfs release\fR [\fB-r\fR] \fItag\fR \fIsnapshot\fR...\fR
3287 Removes a single reference, named with the \fItag\fR argument, from the specified snapshot or snapshots. The tag must already exist for each snapshot.
3295 Recursively releases a hold with the given tag on the snapshots of all descendent file systems.
3303 \fB\fBzfs diff\fR [\fB-FHt\fR] \fIsnapshot\fR \fIsnapshot|filesystem\fR
3307 Display the difference between a snapshot of a given filesystem and another
3308 snapshot of that filesystem from a later time or the current contents of the
3309 filesystem. The first column is a character indicating the type of change,
3310 the other columns indicate pathname, new pathname (in case of rename), change
3311 in link count, and optionally file type and/or change time.
3313 The types of change are:
3316 - The path has been removed
3317 + The path has been created
3318 M The path has been modified
3319 R The path has been renamed
3329 Display an indication of the type of file, in a manner similar to the \fB-F\fR
3330 option of \fBls\fR(1).
3352 Give more parsable tab-separated output, without header lines and without arrows.
3361 Display the path's inode change time as the first column of output.
3366 \fBExample 1 \fRCreating a ZFS File System Hierarchy
3369 The following commands create a file system named \fBpool/home\fR and a file system named \fBpool/home/bob\fR. The mount point \fB/export/home\fR is set for the parent file system, and is automatically inherited by the child file system.
3374 # \fBzfs create pool/home\fR
3375 # \fBzfs set mountpoint=/export/home pool/home\fR
3376 # \fBzfs create pool/home/bob\fR
3382 \fBExample 2 \fRCreating a ZFS Snapshot
3385 The following command creates a snapshot named \fBbackup\fR. This snapshot is mounted on demand in the \fB\&.zfs/snapshot\fR directory at the root of the \fBpool/home/bob\fR file system.
3390 # \fBzfs snapshot pool/home/bob@backup\fR
3396 \fBExample 3 \fRCreating and Destroying Multiple Snapshots
3399 The following command creates snapshots named \fBbackup\fR of \fBpool/home\fR and all of its descendent file systems. Each snapshot is mounted on demand in the \fB\&.zfs/snapshot\fR directory at the root of its file system. The second command destroys the newly created snapshots.
3404 # \fBzfs snapshot -r pool/home@backup\fR
3405 # \fBzfs destroy -r pool/home@backup\fR
3411 \fBExample 4 \fRDisabling and Enabling File System Compression
3414 The following command disables the \fBcompression\fR property for all file systems under \fBpool/home\fR. The next command explicitly enables \fBcompression\fR for \fBpool/home/anne\fR.
3419 # \fBzfs set compression=off pool/home\fR
3420 # \fBzfs set compression=on pool/home/anne\fR
3426 \fBExample 5 \fRListing ZFS Datasets
3429 The following command lists all active file systems and volumes in the system. Snapshots are displayed if the pool's \fBlistsnapshots\fR property is \fBon\fR (the default is \fBoff\fR). See \fBzpool\fR(8) for more information on pool properties.
3435 NAME USED AVAIL REFER MOUNTPOINT
3436 pool 450K 457G 18K /pool
3437 pool/home 315K 457G 21K /export/home
3438 pool/home/anne 18K 457G 18K /export/home/anne
3439 pool/home/bob 276K 457G 276K /export/home/bob
3445 \fBExample 6 \fRSetting a Quota on a ZFS File System
3448 The following command sets a quota of 50 GiB for \fBpool/home/bob\fR.
3453 # \fBzfs set quota=50G pool/home/bob\fR
3459 \fBExample 7 \fRListing ZFS Properties
3462 The following command lists all properties for \fBpool/home/bob\fR.
3467 # \fBzfs get all pool/home/bob\fR
3468 NAME PROPERTY VALUE SOURCE
3469 pool/home/bob type filesystem -
3470 pool/home/bob creation Tue Jul 21 15:53 2009 -
3471 pool/home/bob used 21K -
3472 pool/home/bob available 20.0G -
3473 pool/home/bob referenced 21K -
3474 pool/home/bob compressratio 1.00x -
3475 pool/home/bob mounted yes -
3476 pool/home/bob quota 20G local
3477 pool/home/bob reservation none default
3478 pool/home/bob recordsize 128K default
3479 pool/home/bob mountpoint /pool/home/bob default
3480 pool/home/bob sharenfs off default
3481 pool/home/bob checksum on default
3482 pool/home/bob compression on local
3483 pool/home/bob atime on default
3484 pool/home/bob devices on default
3485 pool/home/bob exec on default
3486 pool/home/bob setuid on default
3487 pool/home/bob readonly off default
3488 pool/home/bob zoned off default
3489 pool/home/bob snapdir hidden default
3490 pool/home/bob acltype off default
3491 pool/home/bob aclinherit restricted default
3492 pool/home/bob canmount on default
3493 pool/home/bob xattr on default
3494 pool/home/bob copies 1 default
3495 pool/home/bob version 4 -
3496 pool/home/bob utf8only off -
3497 pool/home/bob normalization none -
3498 pool/home/bob casesensitivity sensitive -
3499 pool/home/bob vscan off default
3500 pool/home/bob nbmand off default
3501 pool/home/bob sharesmb off default
3502 pool/home/bob refquota none default
3503 pool/home/bob refreservation none default
3504 pool/home/bob primarycache all default
3505 pool/home/bob secondarycache all default
3506 pool/home/bob usedbysnapshots 0 -
3507 pool/home/bob usedbydataset 21K -
3508 pool/home/bob usedbychildren 0 -
3509 pool/home/bob usedbyrefreservation 0 -
3510 pool/home/bob logbias latency default
3511 pool/home/bob dedup off default
3512 pool/home/bob mlslabel none default
3513 pool/home/bob relatime off default
3520 The following command gets a single property value.
3525 # \fBzfs get -H -o value compression pool/home/bob\fR
3533 The following command lists all properties with local settings for \fBpool/home/bob\fR.
3538 # \fBzfs get -r -s local -o name,property,value all pool/home/bob\fR
3540 pool/home/bob quota 20G
3541 pool/home/bob compression on
3547 \fBExample 8 \fRRolling Back a ZFS File System
3550 The following command reverts the contents of \fBpool/home/anne\fR to the snapshot named \fByesterday\fR, deleting all intermediate snapshots.
3555 # \fBzfs rollback -r pool/home/anne@yesterday\fR
3561 \fBExample 9 \fRCreating a ZFS Clone
3564 The following command creates a writable file system whose initial contents are the same as \fBpool/home/bob@yesterday\fR.
3569 # \fBzfs clone pool/home/bob@yesterday pool/clone\fR
3575 \fBExample 10 \fRPromoting a ZFS Clone
3578 The following commands illustrate how to test out changes to a file system, and then replace the original file system with the changed one, using clones, clone promotion, and renaming:
3583 # \fBzfs create pool/project/production\fR
3584 populate /pool/project/production with data
3585 # \fBzfs snapshot pool/project/production@today\fR
3586 # \fBzfs clone pool/project/production@today pool/project/beta\fR
3587 make changes to /pool/project/beta and test them
3588 # \fBzfs promote pool/project/beta\fR
3589 # \fBzfs rename pool/project/production pool/project/legacy\fR
3590 # \fBzfs rename pool/project/beta pool/project/production\fR
3591 once the legacy version is no longer needed, it can be destroyed
3592 # \fBzfs destroy pool/project/legacy\fR
3598 \fBExample 11 \fRInheriting ZFS Properties
3601 The following command causes \fBpool/home/bob\fR and \fBpool/home/anne\fR to inherit the \fBchecksum\fR property from their parent.
3606 # \fBzfs inherit checksum pool/home/bob pool/home/anne\fR
3611 The following command causes \fBpool/home/bob\fR to revert to the received
3612 value for the \fBquota\fR property if it exists.
3617 # \fBzfs inherit -S quota pool/home/bob
3623 \fBExample 12 \fRRemotely Replicating ZFS Data
3626 The following commands send a full stream and then an incremental stream to a remote machine, restoring them into \fBpoolB/received/fs@a\fRand \fBpoolB/received/fs@b\fR, respectively. \fBpoolB\fR must contain the file system \fBpoolB/received\fR, and must not initially contain \fBpoolB/received/fs\fR.
3631 # \fBzfs send pool/fs@a | \e\fR
3632 \fBssh host zfs receive poolB/received/fs@a\fR
3633 # \fBzfs send -i a pool/fs@b | ssh host \e\fR
3634 \fBzfs receive poolB/received/fs\fR
3640 \fBExample 13 \fRUsing the \fBzfs receive\fR \fB-d\fR Option
3643 The following command sends a full stream of \fBpoolA/fsA/fsB@snap\fR to a remote machine, receiving it into \fBpoolB/received/fsA/fsB@snap\fR. The \fBfsA/fsB@snap\fR portion of the received snapshot's name is determined from the name of the sent snapshot. \fBpoolB\fR must contain the file system \fBpoolB/received\fR. If \fBpoolB/received/fsA\fR does not exist, it is created as an empty file system.
3648 # \fBzfs send poolA/fsA/fsB@snap | \e
3649 ssh host zfs receive -d poolB/received\fR
3655 \fBExample 14 \fRSetting User Properties
3658 The following example sets the user-defined \fBcom.example:department\fR property for a dataset.
3663 # \fBzfs set com.example:department=12345 tank/accounting\fR
3669 \fBExample 15 \fRPerforming a Rolling Snapshot
3672 The following example shows how to maintain a history of snapshots with a consistent naming scheme. To keep a week's worth of snapshots, the user destroys the oldest snapshot, renames the remaining snapshots, and then creates a new snapshot, as follows:
3677 # \fBzfs destroy -r pool/users@7daysago\fR
3678 # \fBzfs rename -r pool/users@6daysago @7daysago\fR
3679 # \fBzfs rename -r pool/users@5daysago @6daysago\fR
3680 # \fBzfs rename -r pool/users@4daysago @5daysago\fR
3681 # \fBzfs rename -r pool/users@3daysago @4daysago\fR
3682 # \fBzfs rename -r pool/users@2daysago @3daysago\fR
3683 # \fBzfs rename -r pool/users@yesterday @2daysago\fR
3684 # \fBzfs rename -r pool/users@today @yesterday\fR
3685 # \fBzfs snapshot -r pool/users@today\fR
3691 \fBExample 16 \fRSetting \fBsharenfs\fR Property Options on a ZFS File System
3694 The following commands show how to set \fBsharenfs\fR property options to enable \fBrw\fR access for a set of \fBIP\fR addresses and to enable root access for system \fBneo\fR on the \fBtank/home\fR file system.
3699 # \fBzfs set sharenfs='rw=@123.123.0.0/16,root=neo' tank/home\fR
3706 If you are using \fBDNS\fR for host name resolution, specify the fully qualified hostname.
3709 \fBExample 17 \fRDelegating ZFS Administration Permissions on a ZFS Dataset
3711 The following example shows how to set permissions so that user \fBcindys\fR can create, destroy, mount, and take snapshots on \fBtank/cindys\fR. The permissions on \fBtank/cindys\fR are also displayed.
3716 # \fBzfs allow cindys create,destroy,mount,snapshot tank/cindys\fR
3717 # \fBzfs allow tank/cindys\fR
3718 -------------------------------------------------------------
3719 Local+Descendent permissions on (tank/cindys)
3720 user cindys create,destroy,mount,snapshot
3721 -------------------------------------------------------------
3728 Because the \fBtank/cindys\fR mount point permission is set to 755 by default, user \fBcindys\fR will be unable to mount file systems under \fBtank/cindys\fR. Set an \fBACL\fR similar to the following syntax to provide mount point access:
3732 # \fBchmod A+user:cindys:add_subdirectory:allow /tank/cindys\fR
3738 \fBExample 18 \fRDelegating Create Time Permissions on a ZFS Dataset
3741 The following example shows how to grant anyone in the group \fBstaff\fR to create file systems in \fBtank/users\fR. This syntax also allows staff members to destroy their own file systems, but not destroy anyone else's file system. The permissions on \fBtank/users\fR are also displayed.
3746 # \fBzfs allow staff create,mount tank/users\fR
3747 # \fBzfs allow -c destroy tank/users\fR
3748 # \fBzfs allow tank/users\fR
3749 -------------------------------------------------------------
3750 Create time permissions on (tank/users)
3752 Local+Descendent permissions on (tank/users)
3753 group staff create,mount
3754 -------------------------------------------------------------
3760 \fBExample 19 \fRDefining and Granting a Permission Set on a ZFS Dataset
3763 The following example shows how to define and grant a permission set on the \fBtank/users\fR file system. The permissions on \fBtank/users\fR are also displayed.
3768 # \fBzfs allow -s @pset create,destroy,snapshot,mount tank/users\fR
3769 # \fBzfs allow staff @pset tank/users\fR
3770 # \fBzfs allow tank/users\fR
3771 -------------------------------------------------------------
3772 Permission sets on (tank/users)
3773 @pset create,destroy,mount,snapshot
3774 Create time permissions on (tank/users)
3776 Local+Descendent permissions on (tank/users)
3777 group staff @pset,create,mount
3778 -------------------------------------------------------------
3784 \fBExample 20 \fRDelegating Property Permissions on a ZFS Dataset
3787 The following example shows to grant the ability to set quotas and reservations on the \fBusers/home\fR file system. The permissions on \fBusers/home\fR are also displayed.
3792 # \fBzfs allow cindys quota,reservation users/home\fR
3793 # \fBzfs allow users/home\fR
3794 -------------------------------------------------------------
3795 Local+Descendent permissions on (users/home)
3796 user cindys quota,reservation
3797 -------------------------------------------------------------
3798 cindys% \fBzfs set quota=10G users/home/marks\fR
3799 cindys% \fBzfs get quota users/home/marks\fR
3800 NAME PROPERTY VALUE SOURCE
3801 users/home/marks quota 10G local
3807 \fBExample 21 \fRRemoving ZFS Delegated Permissions on a ZFS Dataset
3810 The following example shows how to remove the snapshot permission from the \fBstaff\fR group on the \fBtank/users\fR file system. The permissions on \fBtank/users\fR are also displayed.
3815 # \fBzfs unallow staff snapshot tank/users\fR
3816 # \fBzfs allow tank/users\fR
3817 -------------------------------------------------------------
3818 Permission sets on (tank/users)
3819 @pset create,destroy,mount,snapshot
3820 Create time permissions on (tank/users)
3822 Local+Descendent permissions on (tank/users)
3823 group staff @pset,create,mount
3824 -------------------------------------------------------------
3830 \fBExample 22\fR Showing the differences between a snapshot and a ZFS Dataset
3833 The following example shows how to see what has changed between a prior
3834 snapshot of a ZFS Dataset and its current state. The \fB-F\fR option is used
3835 to indicate type information for the files affected.
3840 # zfs diff -F tank/test@before tank/test
3842 M F /tank/test/linked (+1)
3843 R F /tank/test/oldname -> /tank/test/newname
3844 - F /tank/test/deleted
3845 + F /tank/test/created
3846 M F /tank/test/modified
3852 \fBExample 23\fR Creating a bookmark
3855 The following example create a bookmark to a snapshot. This bookmark can then
3856 be used instead of snapshot in send streams.
3861 # zfs bookmark rpool@snapshot rpool#bookmark
3866 .SH "ENVIRONMENT VARIABLES"
3869 Cause \fBzfs\fR to dump core on exit for the purposes of running \fB::findleaks\fR.
3873 The following exit values are returned:
3881 Successful completion.
3901 Invalid command line options were specified.
3906 \fBchmod\fR(2), \fBfsync\fR(2), \fBgzip\fR(1), \fBls\fR(1), \fBmount\fR(8), \fBopen\fR(2), \fBreaddir\fR(3), \fBssh\fR(1), \fBstat\fR(2), \fBwrite\fR(2), \fBzpool\fR(8), \fBzfs-module-parameters\fR(5)
3908 On Solaris: \fBdfstab(4)\fR, \fBiscsitadm(1M)\fR, \fBmount(1M)\fR, \fBshare(1M)\fR, \fBsharemgr(1M)\fR, \fBunshare(1M)\fR
projects / mirror_zfs.git / blob