svcadm(1M)을 검색하려면 섹션에서 1M 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.
zfs(8)
System Administration Commands zfs(8)
NAME
zfs - configures ZFS file systems
SYNOPSIS
zfs [-?]
zfs help subcommand | help | property property-name | permission
zfs help -l properties
zfs allow filesystem|volume
zfs allow [-ldug] everyone|user|group[,...] perm|@setname[,...]
filesystem|volume
zfs allow [-ld] -e perm|@setname[,...] filesystem|volume
zfs allow -c perm|@setname[,...] filesystem|volume
zfs allow -s @setname perm|@setname[,...] filesystem|volume
zfs clone [-p] [-K] [-o property=value] ... snapshot filesystem|volume
zfs create [-p] [-o property=value] ... filesystem
zfs create [-ps] [-b blocksize] [-o property=value] ... -V size volume
zfs destroy [-rRsf] filesystem|volume
zfs destroy [-rRsd] snapshot
zfs destroy share
zfs diff [-FHNqrte] [-o field] ... snapshot [snapshot|filesystem]
zfs diff -E [-FHqrt] [-o field] ... snapshot|filesystem
zfs get [-rHpe|-d max] [-o all | field[,...]] [-s source[,...]]
[-I state,...] all | property[,...]
filesystem|volume|snapshot|share ...
zfs get share [filesystem]
zfs groupspace [-hniHp] [-o field[,...]] [-sS field] ...
[-t type [,...]] filesystem|snapshot
zfs hold [-r] tag snapshot...
zfs holds [-r] snapshot...
zfs key -l {-a | [-r] filesystem|volume}
zfs key -u [-f] {-a | [-r] filesystem|volume}
zfs key -c [-o keysource=value] {-a | [-r] filesystem|volume}
zfs key -K {-a | [-r] filesystem|volume}
zfs list [-rH|-d max][-o property[,...]] [-t type[,...]] [-I state,..]
[-s property] ... [-S property] ...
[filesystem|volume|snapshot|share|path] ...
zfs inherit [-rS] property filesystem|volume|snapshot|share ...
zfs mount
zfs mount [-vO] [-o options] -a | filesystem
zfs promote clone-filesystem
zfs receive [-vnFu] [[-o property=value] | [-x property]] ...
filesystem|volume|snapshot
zfs receive [-vnFu] [[-o property=value] | [-x property]] ...
[-d | -e] filesystem
zfs receive -C filesystem|volume
zfs release [-r] tag snapshot...
zfs rename filesystem|volume|snapshot
filesystem|volume|snapshot
zfs rename [-p] filesystem|volume filesystem|volume
zfs rename -r snapshot snapshot
zfs rename share share
zfs rollback [-rRf] snapshot
zfs send [-vbpnC] [-Rr[c]] [-w compress|none]
[-D [-m memsize]]
[-iI snapshot] [-s subopt] snapshot
zfs set [-r] property=value filesystem|volume|snapshot ...
zfs share -u [-o property=value] filesystem%share
zfs share filesystem|mountpoint|filesystem%share
zfs share -a| -r | filesystem
zfs snapshot [-r] [-o property=value]...
filesystem@snapname|volume@snapname
zfs unmount [-f] -a | filesystem|mountpoint
zfs unshare filesystem|mountpoint|filesystem%share
zfs unshare -a| -r filesystem|
zfs upgrade
zfs upgrade [-v]
zfs upgrade [-r] [-V version] -a | filesystem
zfs userspace [-hniHp] [-o field[,...]] [-sS field] ...
[-t type [,...]] filesystem|snapshot
zfs unallow [-rldug] everyone|user|group[,...] [perm|@setname[,... ]]
filesystem|volume
zfs unallow [-rld] -e [perm|@setname[,... ]] filesystem|volume
zfs unallow [-r] -c [perm|@setname[ ... ]] filesystem|volume
zfs unallow [-r] -s @setname [perm|@setname[,... ]] filesystem|volume
DESCRIPTION
The zfs command configures ZFS datasets within a ZFS storage pool, as
described in zpool(8). A dataset is identified by a unique path within
the ZFS namespace. For example:
pool/{filesystem,volume,snapshot}
where the maximum length of a dataset name is MAXNAMELEN (256 bytes).
A dataset can be one of the following:
file system
A ZFS dataset of type filesystem can be mounted within the standard
system namespace and behaves like other file systems. While ZFS
file systems are designed to be POSIX compliant, known issues exist
that prevent compliance in some cases. Applications that depend on
standards conformance might fail due to nonstandard behavior when
checking free file system space.
volume
A logical volume exported as a raw or block device. This type of
dataset should only be used under special circumstances. File sys‐
tems are typically used in most environments.
snapshot
A read-only version of a file system or volume at a given point in
time. It is specified as filesystem@name or volume@name.
ZFS File System Hierarchy
A ZFS storage pool is a logical collection of devices that provide
space for datasets. A storage pool is also the root of the ZFS file
system hierarchy.
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 zpool(8) command.
See zpool(8) for more information on creating and administering pools.
Snapshots
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.
Snapshots can have arbitrary names. Snapshots of volumes can be cloned
or rolled back, but cannot be accessed independently.
File system snapshots can be accessed under the .zfs/snapshot 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
.zfs directory can be controlled by the snapdir property.
Clones
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.
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 origin property exposes this dependency, and the destroy command
lists any such dependencies, if they exist.
The clone parent-child dependency relationship can be reversed by using
the promote 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.
Mount Points
Creating a ZFS file system is a simple operation, so the number of file
systems per system is likely to be numerous. To cope with this, ZFS
automatically manages mounting and unmounting file systems without the
need to edit the /etc/vfstab file. All automatically managed file sys‐
tems are mounted by ZFS at boot time.
By default, file systems are mounted under /path, where path is the
name of the file system in the ZFS namespace. Directories are created
and destroyed as needed.
A file system can also have a mount point set in the mountpoint prop‐
erty. This directory is created as needed, and ZFS automatically mounts
the file system when the zfs mount -a command is invoked (without edit‐
ing /etc/vfstab). The mountpoint property can be inherited, so if
pool/home has a mount point of /export/stuff, then pool/home/user auto‐
matically inherits a mount point of /export/stuff/user.
A file system can be mounted temporarily at a location other than the
file systems persistent mount point by specifying the -o mount‐
point=value option to the zfs mount command. This is only permitted for
file systems with non-legacy mount points.
A file system mountpoint property of none prevents the file system from
being mounted.
If needed, ZFS file systems can also be managed with traditional tools
(mount, umount, /etc/vfstab). If a file system's mount point is set to
legacy, ZFS makes no attempt to manage the file system, and the admin‐
istrator is responsible for mounting and unmounting the file system.
Zones
The physical properties of an added file system are controlled by the
global administrator. However, the zone administrator can create, mod‐
ify, or destroy files within the added file system, depending on how
the file system is mounted.
A dataset can also be delegated to a non-global zone by using the
zonecfg add dataset subcommand. You cannot delegate a dataset to one
zone and the children of the same dataset to another zone. The zone
administrator can change properties of the dataset or any of its chil‐
dren. However, the quota property is controlled by the global adminis‐
trator.
A ZFS volume can be added as a device to a non-global zone by using the
zonecfg add device subcommand. However, its physical properties can be
modified only by the global administrator.
For more information about zonecfg syntax, see the zonecfg(8) man page.
After a dataset is delegated to a non-global zone, the zoned property
is automatically set. A zoned file system can only be mounted in the
global zone by using a temporary mountpoint property (see "Temporary
Mount Point Properties").
The global administrator can forcibly clear the zoned property, though
this should be done with extreme care. The global administrator should
verify that all the mount points are acceptable before clearing the
property.
Deduplication
Deduplication is the process of removing redundant data at the block-
level, reducing the total amount of data stored. Deduplication is pool-
wide; each dataset can opt in or out using its own dedup property. If a
file system has the dedup property enabled, duplicate data blocks are
removed synchronously on write. The result is that only unique data are
stored and common components are shared among files in all datasets in
the pool that have dedup enabled.
Encryption
For a full description of ZFS encryption and the ZFS encryption syntax,
see zfs_encrypt(8).
Native Properties
Properties are divided into two types, native properties and user-
defined (or user) properties. Native properties either provide internal
statistics or control ZFS behavior. In addition, native properties are
either editable or read-only. User properties have no effect on ZFS
behavior, but you can use them to annotate datasets in a way that is
meaningful in your environment. For more information about user proper‐
ties, see the "User Properties" section, below.
Every dataset has a set of properties that provide statistics about the
dataset as well as control various behaviors. Properties are inherited
from the parent unless overridden by the child. Some properties apply
only to certain types of datasets (file systems, volumes, or snap‐
shots).
The values of numeric properties can be specified using human-readable
suffixes (for example, k, KB, M, Gb, and so forth, up to Z for
zettabyte). The following are all valid (and equal) specifications:
1536M, 1.5g, 1.50GB
The values of non-numeric properties are case-sensitive and must be
lowercase, except for the mountpoint property.
The following native properties consist of read-only statistics about
the dataset. These properties can be neither set, nor inherited. Native
properties apply to all dataset types unless otherwise noted.
available
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.
This property can also be referred to by its shortened column name,
avail.
compressratio
The compression ratio achieved for this dataset, expressed as a
multiplier. Compression can be turned on by running: zfs set com‐
pression=on dataset. The default value is off.
creation
The time this dataset was created.
defer_destroy
This property is on if the snapshot has been marked for deferred
destroy by using the zfs destroy -d command. Otherwise, the prop‐
erty is off.
keychangedate
For more information, see zfs_encrypt(8).
keystatus
For more information, see zfs_encrypt(8).
mounted
For file systems, indicates whether the file system is currently
mounted. This property can be either yes or no.
origin
For cloned file systems or volumes, the snapshot from which the
clone was created. The origin cannot be destroyed (even with the -r
or -f options) so long as a clone exists.
referenced
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.
This property can also be referred to by its shortened column name,
refer.
rekeydate
For more information, see zfs_encrypt(8).
type
The type of dataset: filesystem, volume, or snapshot.
used
The amount of space consumed by this dataset and all its descen‐
dents. 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 refreservation
(through usedbyrefreservation) and the reservations of any descen‐
dent datasets (through usedbychildren). 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.
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.
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 fsync(3C) or O_SYNC does not necessarily guarantee that the
space usage information is updated immediately.
usedby*
The usedby* properties decompose the used properties into the vari‐
ous reasons that space is used. Specifically, used = usedbychildren
+ usedbydataset + usedbyrefreservation +, usedbysnapshots. These
properties are only available for datasets created on pools that
are version 13 or higher.
usedbychildren
The amount of space used by children of this dataset, which would
be freed if all the dataset's children were destroyed.
usedbydataset
The amount of space used by this dataset itself, which would be
freed if the dataset was destroyed (after first removing any
refreservation and destroying any necessary snapshots or descen‐
dents).
usedbyrefreservation
The amount of space used by a refreservation set on this dataset,
which would be freed if the refreservation was removed.
Space accounted for by this property represents potential consump‐
tion by future writes, reserved in advance to prevent write alloca‐
tion failures in this dataset. This can include unwritten data,
space currently shared with snapshots, and compression savings for
volumes (which may be lost when replaced with less compressible
data). When allocations for later writes increase usedbydataset or
usedbysnapshots, usedbyrefreservation will decrease accordingly.
usedbysnapshots
The amount of space consumed by snapshots of this dataset. In par‐
ticular, it is the amount of space that would be freed if all of
this dataset's snapshots were destroyed. Note that this is not sim‐
ply the sum of the snapshots' used properties because space can be
shared by multiple snapshots.
userused@user
The amount of space consumed by the specified user in this dataset.
Space is charged to the owner of each file, as displayed by ls -l.
The amount of space charged is displayed by du and ls -s. See the
zfs userspace subcommand for more information.
Unprivileged users can access only their own space usage. The root
user, or a user who has been granted the userused privilege with
zfs allow, can access everyone's usage.
The userused@... properties are not displayed by zfs get all. The
user's name must be appended after the @ symbol, using one of the
following forms:
o POSIX name (for example, joe)
o POSIX numeric ID (for example, 789)
o SID name (for example, joe.smith@mydomain)
o SID numeric ID (for example, S-1-123-456-789)
userrefs
This property is set to the number of user holds on this snapshot.
User holds are set by using the zfs hold command.
groupused@group
The amount of space consumed by the specified group in this
dataset. Space is charged to the group of each file, as displayed
by ls -l. See the userused@user property for more information.
Unprivileged users can only access their own groups' space usage.
The root user, or a user who has been granted the groupused privi‐
lege with zfs allow, can access all groups' usage.
volblocksize=blocksize
For volumes, specifies the block size of the volume. The blocksize
cannot be changed once the volume has been written, so it should be
set at volume creation time. The default blocksize for volumes is 8
KB. Any power of 2 from 512 bytes to 1 MB is valid.
This property can also be referred to by its shortened column name,
volblock.
effectivereadlimit
effectivewritelimit
These properties provide a view of what the effective limit is on a
dataset. The value displayed indicates the maximum throughput the
dataset is governed by. The reported effective limit is the lowest
data limit at any point between the root and the indicated dataset.
See readlimit and writelimit for more details on limit behavior.
The following native properties can be used to change the behavior of a
ZFS dataset.
aclmode=discard | mask | passthrough
Controls how an ACL is modified during chmod(2). A file system with
an aclmode property of discard (the default) deletes all ACL
entries that do not represent the mode of the file. An aclmode
property of mask reduces user or group permissions. The permissions
are reduced so that they are no greater than the group permission
bits, unless it is a user entry that has the same UID as the owner
of the file or directory. In this case, the ACL permissions are
reduced so that they are no greater than owner permission bits.
mask also preserves the ACL across mode changes (without an
explicit ACL set [by means of chmod(1)] between the mode changes).
A file system with an aclmode property of passthrough indicates
that no changes will be made to the ACL other than generating the
necessary ACL entries to represent the new mode of the file or
directory.
refreservation=size | none | auto
The minimum amount of space guaranteed to a dataset, not including
its descendents. The default refreservation is none for file sys‐
tems.
For ZFS volumes, the refreservation is automatically set to a
slightly larger size than the actual volume size to account for ZFS
metadata overhead. You can use the dense value to reserve enough
space for both data and metadata for the current volume size. For
example, if you need more space for other file systems, you can
temporarily reduce a volume's refreservation value, which converts
this to a sparse volume. Then, you can revert the volume refreser‐
vation value back to the original value when it was created by
specifying the dense value.
When the usedbydataset space is below this value, the dataset is
treated as if it were taking up the amount of space specified by
refreservation. The usedbyrefreservation figure represents this
extra space, adding to the total used space charged to the dataset,
and in turn consuming from the parent datasets' usage, quotas, and
reservations. This protects the dataset from overcommitment of pool
resources, by ensuring that space for future writes is reserved in
advance.
Space shared with snapshots can later be replaced with new data,
and the snapshot represents a commitment to keep both copies. If
refreservation is set, usedbyrefreservation must be increased to
the full size of refreservation when taking a new snapshot,
accounting for this commitment. If there is insufficient space
available to the dataset for this increase, snapshot creation will
be denied.
This property can also be referred to by its shortened column name,
refreserv.
aclinherit=discard | noallow | restricted | passthrough | passthrough-x
passthrough-mode-preserve
Controls how ACL entries are inherited when files and directories
are created. A file system with an aclinherit property of discard
does not inherit any ACL entries. A file system with an aclinherit
property value of noallow only inherits inheritable ACL entries
that specify "deny" permissions. The property value restricted (the
default) removes the write_acl and write_owner permissions when the
ACL entry is inherited. A file system with an aclinherit property
value of passthrough inherits all inheritable ACL entries without
any modifications made to the ACL entries when they are inherited.
A file system with an aclinherit property value of passthrough-x
has the same meaning as passthrough, except that all ACEs inherit
the execute permission only if the file creation mode also requests
the execute bit. A file system with aclinherit property value of
passthrough-mode-preserve has the same semantics as "passthrough"
except that the owner@, group@, and everyone@ ACEs are overridden
with values from the mode requested by the application when creat‐
ing files and directories.
When the property value is set to passthrough, files are created
with a mode determined by the inheritable ACEs. If no inheritable
ACEs exist that affect the mode, then the mode is set in accordance
to the requested mode from the application.
atime=on | off
Controls whether the access time for files is updated when they are
read. Turning this property off 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 on.
canmount=on | off | noauto
If this property is set to off, the file system cannot be mounted,
and is ignored by zfs mount -a. Setting this property to off is
similar to setting the mountpoint property to none, except that the
dataset still has a normal mountpoint property, which can be inher‐
ited. Setting this property to off allows datasets to be used
solely as a mechanism to inherit properties. One example of setting
canmount=off is to have two datasets with the same mountpoint, so
that the children of both datasets appear in the same directory,
but might have different inherited characteristics.
When the noauto 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 zfs
mount -a command or unmounted by the zfs unmount -a command.
This property is not inherited.
checksum=on | off | fletcher2 | fletcher4 | sha256 | sha256+mac
Controls the checksum used to verify data integrity. The default
value is on, which automatically selects an appropriate algorithm
(currently fletcher4, but this may change in future releases). The
value off disables integrity checking on user data. Disabling
checksums is NOT a recommended practice.
Changing this property affects only newly-written data.
The value of sha256+mac is only available when encryption is
enabled. The checksum property becomes readonly when encryption is
enabled, and then is always set to sha256+mac.
compression=on | off | lzjb | gzip | gzip-N | zle | lz4
Controls the compression algorithm used for this dataset. The lzjb
compression algorithm is optimized for performance while providing
decent data compression. Setting compression to on uses the lzjb
compression algorithm. The gzip compression algorithm uses the same
compression as the gzip(1) command. You can specify the gzip level
by using the value gzip-N where N is an integer from 1 (fastest) to
9 (best compression ratio). Currently, gzip is equivalent to gzip-6
(which is also the default for gzip(1)). lz4 provides better com‐
pression than lzjb with lower CPU overhead. Neither gzip nor lz4
compression is currently supported when set at the root pool level
nor on the root pool dataset.
This property can also be referred to by its shortened column name
compress. Changing this property affects only newly-written data.
copies=1 | 2 | 3
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 used prop‐
erty and counting against quotas and reservations.
Changing this property only affects newly-written data. Therefore,
set this property at file system creation time by using the -o
copies=N option.
When encryption is enabled on a dataset, copies can be set to a
maximum of 2.
When the dataset is an auto-provisioned ZFS volume, change of the
copies induces change to the refreservation as well. See the
"refreservation" for details.
dedup=on | off | verify | sha256[,verify]
Controls whether deduplication is in effect for a dataset. The
default value is off. The default checksum used for deduplication
is sha256 (subject to change). When dedup is enabled, the dedup
checksum algorithm overrides the checksum property. Setting the
value to verify is equivalent to specifying sha256,verify.
If the property is set to verify, 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.
devices=on | off
Controls whether device nodes can be opened on this file system.
The default value is on.
exec=on | off
Controls whether processes can be executed from within this file
system. The default value is on.
logbias = latency | throughput
Controls how ZFS optimizes synchronous requests for this dataset.
If logbias is set to latency, ZFS uses the pool's separate log
devices, if any, to handle the requests at low latency. If logbias
is set to throughput, ZFS does not use the pool's separate log
devices. Instead, ZFS optimizes synchronous operations for global
pool throughput and efficient use of resources. The default value
is latency.
mlslabel=label | none
See the multilevel property for a description of the behavior of
the mlslabel property on multilevel file systems. The following
mlslabel description applies to non-multilevel file systems:
The mlslabel property is a sensitivity label that determines if a
dataset can be mounted in a zone on a system with Trusted Exten‐
sions enabled. If the labeled dataset matches the labeled zone, the
dataset can be mounted and accessed from the labeled zone.
When the mlslabel property is not set, the default value is none.
Setting the mlslabel property to none is equivalent to removing the
property.
The mlslabel 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 {PRIV_FILE_UPGRADE_SL} priv‐
ilege is required. When changing a label to a lower label or the
default (none), the {PRIV_FILE_DOWNGRADE_SL} 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 mlslabel property to the label of that zone.
When Trusted Extensions is not enabled, only datasets with the
default label (none) can be mounted.
mountpoint=path | none | legacy
Controls the mount point used for this file system. See the "Mount
Points" section for more information on how this property is used.
When the mountpoint 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 legacy, then they remain unmounted. Otherwise,
they are automatically remounted in the new location if the prop‐
erty was previously legacy or none, or if they were mounted before
the property was changed. In addition, any shared file systems are
unshared and shared in the new location.
nbmand=on | off
For more information, see zfs_share(8).
primarycache=all | none | metadata
Controls what is cached in the primary cache (ARC). If this prop‐
erty is set to all, then both user data and metadata is cached. If
this property is set to none, then neither user data nor metadata
is cached. If this property is set to metadata, then only metadata
is cached. The default value is all.
quota=size | none
Limits the amount of space a dataset and its descendents can con‐
sume. This includes all space consumed by descendents, including
file systems and snapshots. Enforcement of quotas may be delayed by
several seconds. This delay means that a user might exceed their
quota before the system notices that the user is over quota. The
system would then begin to refuse additional writes. 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. Quotas cannot be set on volumes, as the volsize property
acts as an implicit quota.
readlimit=size | none | default
writelimit=size | none | default
Limits the rate in bytes/second at which a dataset will be read or
written to. A limit imposed on a dataset will apply to that dataset
and all of its descendents. A value of 'none' overrides any default
set by a parent. A value of 'default' will return the dataset to
any default that was set by a parent. These values are not a guar‐
anteed bandwidth and the actual bandwidth can be limited by other
factors, including usage and limits set on other datasets in the
hierarchy. Enforcement of these limits may be delayed by several
seconds.
defaultreadlimit=size | none
defaultwritelimit=size | none
Sets a default limit for a dataset in bytes per second at which a
dataset will be read or written to. A default limit imposed on a
dataset will only apply to the datasets descendants. This value is
inherited by the descendants and can be overridden by setting the
readlimit or writelimit value on the descendent. These values are
not a guaranteed bandwidth and the actual bandwidth can be limited
by other factors including usage and limits set on other datasets
in the hierarchy. Enforcement of these limits may be delayed by
several seconds.
sync=standard | always | disabled
Determines the degree to which file system transactions are syn‐
chronized. This property can be set when a dataset is created, or
dynamically, and will take effect immediately. This property can
have one of the following settings:
standard
The default option. Synchronous file system transactions are
written to the intent log and then all devices written are
flushed to ensure the data is stable (that is, not cached by
device controllers).
always
Each file system transaction is written and flushed to stable
storage. This value has a significant performance penalty but
might be appropriate for troubleshooting synchronous file sys‐
tem transactions.
disabled
Synchronous requests are disabled. File system transactions
commit to stable storage only on the next DMU transaction group
commit, which might be after many seconds. This setting gives
the highest performance. However, it is very dangerous as ZFS
would be ignoring the synchronous transaction demands of appli‐
cations such as databases or NFS. Furthermore, when this set‐
ting is in effect for the currently active root or /var
filesystem, out-of-spec behavior, application data loss, and
increased vulnerability to replay attacks can result. Adminis‐
trators should only use this option only when these risks are
understood.
defaultuserquota=size | none
Sets the default user quota. The default value is none. This value
will apply to all users who do not have an explicit userquota spec‐
ified.
defaultgroupquota=size | none
Sets the default group quota. The default value is none. This value
will apply to all groups who do not have an explicit userquota
specified.
userquota@user=size | none | default
Limits the amount of space consumed by the specified user. Similar
to the refquota property, the userquota space calculation does not
include space that is used by descendent datasets, such as snap‐
shots and clones. User space consumption is identified by the
userspace@user property.
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 the user is over quota. The system would then begin to
refuse additional writes with the EDQUOT error message. See the zfs
userspace subcommand for more information.
Unprivileged users can only access their own groups' space usage.
The root user, or a user who has been granted the userquota privi‐
lege with zfs allow, can get and set everyone's quota.
This property is not available on volumes, on file systems before
version 4, or on pools before version 15. The userquota@... proper‐
ties are not displayed by zfs get all. The user's name must be
appended after the @ symbol, using one of the following forms:
o POSIX name (for example, joe)
o POSIX numeric ID (for example, 789)
o SID name (for example, joe.smith@mydomain)
o SID numeric ID (for example, S-1-123-456-789)
A value of default resets the quota to the default value defined by
the defaultuserquota property.
groupquota@group=size | none | default
Limits the amount of space consumed by the specified group. Group
space consumption is identified by the userquota@user property.
Unprivileged users can access only their own groups' space usage.
The root user, or a user who has been granted the groupquota privi‐
lege with zfs allow, can get and set all groups' quotas.
A value of default resets the groupquota to the default value
defined by the defaultgroupquota property.
readonly=on | off
Controls whether this dataset can be modified. The default value is
off.
This property can also be referred to by its shortened column name,
rdonly.
recordsize=size
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. ZFS automatically tunes block
sizes according to internal algorithms optimized for typical access
patterns.
For databases that create very large files but access them in small
random chunks, these algorithms may be suboptimal. Specifying a
recordsize 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.
The default recordsize is 128 KB. The size specified must be a
power of two greater than or equal to 512 and less than or equal to
1 MB.
Changing the file system's recordsize affects only files created
afterward; existing files and received data are unaffected.
This property can also be referred to by its shortened column name,
recsize.
refquota=size | none
Limits the amount of space a dataset can consume. This limit does
not include space used by descendents, including file systems and
snapshots. Enforcement of refquotas may be delayed by several sec‐
onds. This delay means that a user might exceed their quota before
the system notices that the user is over quota. The system would
then begin to refuse additional writes.
refreservation=size | none | auto
The minimum amount of space guaranteed to a dataset, not including
its descendents.
The default refreservation is auto for ZFS volumes and none for
other types of datasets. When refreservation=auto, sufficient space
is reserved for the volume to store its designated volume size
(volsize) and associated metadata. This effective reservation
depends on both volsize and copies properties. A volume can also be
manually provisioned by setting refreservation to a numeric value
(for example, zfs set refreservation=10g). Because of metadata, the
actual space that is guaranteed for volume data will be slightly
less than the requested numeric refreservation. A sparse volume
(for example, when -s is specified at volume creation) is equiva‐
lent to one with a refreservation of none. Note that, refreserva‐
tion=auto applies only to ZFS volumes.
Space that is reserved for a volume but that is not currently used
by that volume is accounted for in usedbyrefreservation. Thus, the
effective total refreservation for a zfs volume is always the sum
of usedbydataset and usedbyrefreservation. This entire sum consumes
from the parent datasets' usage, quotas, and reservations. This
protects each dataset from overcommitment of pool resources, by
ensuring that space for future writes is reserved in advance.
Space shared with snapshots can later be replaced with new data,
and the snapshot represents a commitment to keep both copies. If
refreservation is set, usedbyrefreservation must be increased to
the full size of refreservation when taking a new snapshot,
accounting for this commitment. If there is insufficient space
available to the dataset for this increase, snapshot creation will
be denied.
This property can also be referred to by its shortened column name,
refreserv.
reservation=size | none
The minimum amount of space guaranteed to a dataset and its descen‐
dents. 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.
This property can also be referred to by its shortened column name,
reserv.
rstchown=on | off
Indicates whether the file system restricts users from giving away
their files by means of chown(1) or the chown(2) system call. The
default is to restrict chown. When rstchown is off then chown will
act as if the user has the PRIV_FILE_CHOWN_SELF privilege.
secondarycache=all | none | metadata
Controls what is cached in the secondary cache (L2ARC). If this
property is set to all, then both user data and metadata is cached.
If this property is set to none, then neither user data nor meta‐
data is cached. If this property is set to metadata, then only
metadata is cached. The default value is all.
setuid=on | off
Controls whether the set-UID bit is respected for the file system.
The default value is on.
shadow=URI | none
Identifies a ZFS file system as a shadow of the file system
described by the URI. Data is migrated to a shadow file system with
this property set from the file system identified by the URI. The
file system to be migrated must be read-only for a complete migra‐
tion.
Access to a directory that is not yet migrated in the shadow file
system is blocked until the entire directory is migrated. Access to
a file that is not yet migrated in the shadow file system causes
only a portion of the file being accessed to be migrated. Multiple
processes can migrate different portions of a file at the same
time.
Two forms of URI are accepted, one for migrating a local file sys‐
tem to another file system on the same physical system, and one for
remotely migrating a file system from an NFS server. The forms are:
file:///path
nfs://host/path
If shadowd(8) is still running when the migration is complete, the
file system is automatically remounted with the shadow property set
to none. Or, when the migration is complete, you can manually set
the shadow property to none.
sharenfs=on | off
For more information, see zfs_share(8).
sharesmb=on | off
For more information, see zfs_share(8).
snapdir=hidden | visible
Controls whether the .zfs directory is hidden or visible in the
root of the file system as discussed in the "Snapshots" section.
The default value is hidden.
version=1 | 2 | current
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. See the zfs upgrade command.
volsize=size
Specifies the logical size of the volume. By default, creating a
volume establishes a refreservation that is a somewhat larger than
the actual logical volume size, to account for ZFS metadata over‐
head. Any changes to volsize are reflected in an equivalent change
to the refreservation. The volsize can only be set to a multiple of
volblocksize, and cannot be zero.
The refreservation is set on the volume to prevent unexpected
behavior for consumers. Without the reservation, the volume could
run out of space, resulting in undefined behavior or data corrup‐
tion, depending on how the volume is used. These effects can also
occur when the volume size is changed while it is in use (particu‐
larly when shrinking the size). Extreme care should be used when
adjusting the volume size. If the volume is auto-provisioned,
change of its size also induces a change to the refreservation. For
more information, see the "refreservation" section.
Though not recommended, a sparse volume (also known as thin provi‐
sioning) can be created by specifying the -s option to the zfs cre‐
ate -V command. A sparse volume is a volume where the reservation
is less then the volume size. Consequently, writes to a sparse vol‐
ume can fail with ENOSPC when the pool is low on space. For a
sparse volume, changes to volsize are not reflected in the reserva‐
tion.
vscan=on | off
For more information, see the zfs_share(8) man page.
xattr=on | off
Controls whether extended attributes are enabled for this file sys‐
tem. The default value is on.
zoned=on | off
Controls whether the dataset is managed from a non-global zone. See
the "Zones" section for more information. The default value is off.
The following 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 zfs create or zpool create com‐
mands, 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.
casesensitivity=sensitive | insensitive | mixed
For more information, see zfs_share(8).
normalization = none | formC | formD | formKC | formKD
For more information, see zfs_share(8).
utf8only=on | off
For more information, see zfs_share(8).
encryption=off | on | aes-128-ccm | aes-192-ccm | aes-256-ccm |
aes-128-gcm | aes-192-gcm | aes-256-gcm
For more information, see zfs_encrypt(8).
multilevel=on | off
The default value is off. It cannot be turned off after it set to
on.
Objects in a multilevel file system are individually labeled with
an explicit sensitivity label attribute that is automatically gen‐
erated. Objects can be relabeled in place by changing this label
attribute, by using the setlabel(1) or setflabel(3TSOL) interfaces.
Zone datasets, system root datasets, and other datasets containing
packaged Solaris code should not be multilevel.
The upper bound of a multilevel file system is maintained in the
mlslabel property. Normally the mlslabel is managed automatically
by the system. It is set to ADMIN_LOW when the multilevel property
is set on, and floats up to represent the maximum sensitivity label
as files and directories are upgraded. After creating a multilevel
file system, the mlslabel cannot be changed to a lower label,
removed, or set to none.
When Trusted Extensions is enabled the mlslabel value defines the
highest possible label that objects in the file system can have.
Attempts to create a file at (or relabel a file to) a label higher
than the mlslabel is not allowed. The mlslabel property can be set
explicitly during file system creation, otherwise a default mlsla‐
bel property of ADMIN_HIGH will be automatically created. The mount
policy based on mlslabel does not apply to multilevel file systems.
The following property must be specified at creation time and can modi‐
fied by using special commands:
keysource=raw | hex | passphrase,prompt | file
For more information, see zfs_encrypt(8).
Temporary Mount Point Properties
When a file system is mounted, either through the legacy mount(8) com‐
mand or the zfs mount command, its mount options are set according to
its properties. The correlation between properties and mount options is
as follows:
PROPERTY MOUNT OPTION
devices devices/nodevices
mountpoint mountpoint
exec exec/noexec
readonly ro/rw
setuid setuid/nosetuid
xattr xattr/noxattr
rstchown rstchown/norstchown
In addition, these options can be set on a per-mount basis using the -o
option, without affecting the property that is stored on disk. The val‐
ues specified on the command line override the values stored in the
dataset. The -nosuid option is an alias for nodevices,nosetuid. These
properties are reported as temporary by the zfs get command. If the
properties are changed while the dataset is mounted, the new setting
overrides any temporary settings. If the property being modified is the
mountpoint, the dataset will be immediately unmounted from the tempo‐
rary mountpoint and remounted at the new persistent mountpoint.
User Properties
In addition to the standard native properties, ZFS supports arbitrary
user properties. User properties have no effect on ZFS behavior, but
applications or administrators can use them to annotate datasets (file
systems, volumes, and snapshots).
User property names must contain a colon (:) character to distinguish
them from native properties. They may contain lowercase letters, num‐
bers, and the following punctuation characters: colon (:), dash (-),
period (.), and underscore (_). The expected convention is that the
property name is divided into two portions such as module:property, but
this namespace is not enforced by ZFS. User property names can be at
most 256 characters, and cannot begin with a dash (-).
When making programmatic use of user properties, it is strongly sug‐
gested to use a reversed DNS domain name for the module component of
property names to reduce the chance that two independently-developed
packages use the same property name for different purposes. In the Ora‐
cle Solaris release, the com.oracle user property is reserved for beadm
command and library. The com.oracle:rootfs is reserved for Oracle
Solaris boot. It defines the root filesystem dataset associated with a
bootable dataset.
The values of user properties are arbitrary strings, are always inher‐
ited, and are never validated. All of the commands that operate on
properties (zfs list, zfs get, zfs set, and so forth) can be used to
manipulate both native properties and user properties. Use the zfs
inherit 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.
ZFS Volumes as Swap or Dump Devices
During an initial installation, a swap device and dump device are cre‐
ated on ZFS volumes in the ZFS root pool. Separate ZFS volumes must be
used for the swap area and dump devices. Do not swap to a file on a ZFS
file system. A ZFS swap file configuration is not supported.
You can encrypt a ZFS volume used as a swap device by specifying the
encryption property for that device and specifying the encrypted option
in vfstab(5). For more information about the encryption property, see
zfs_encrypt(8).
If you need to change your swap area or dump device after the system is
installed or upgraded, use the swap(8) and dumpadm(8) commands. If you
need to change the size of your swap area or dump device, see the Man‐
aging ZFS File Systems in Oracle Solaris 11.4 book.
SUBCOMMANDS
All subcommands that modify state are logged persistently to the pool
in their original form.
zfs ?
Displays a help message.
zfs help command | help | property property-name | permission
Displays zfs command usage information. You can display help for a
specific command, property, or delegated permission. If you display
help for a specific command or property, the command syntax or
property value is displayed. Using zfs help without any arguments
displays a complete list of zfs commands.
zfs help -l properties
Displays zfs property information, including whether the property
value is editable and inheritable, and their possible values.
zfs allow filesystem | volume
zfs allow [-ldug] everyone|user|group[,...] perm|@setname[,...]
filesystem| volume
zfs allow [-ld] -e perm|@setname[,...] filesystem|volume
zfs allow -c perm|@setname[,...] filesystem|volume
zfs allow -s @setname perm|@setname[,...] filesystem|volume
For a full description of the zfs allow syntax and examples, see
zfs_allow(8).
zfs clone [-p] [-K] [-o property=value] ... snapshot filesystem|volume
Creates a clone of the given snapshot. See the "Clones" section for
details. The target dataset can be located anywhere in the ZFS
hierarchy, and is created as the same type as the original.
-p
Creates all the non-existing parent datasets. Datasets created
in this manner are automatically mounted according to the
mountpoint property inherited from their parent. If the target
file system or volume already exists, the operation completes
successfully.
-o property=value
Sets the specified property; see zfs create for details.
-K
For information, see zfs_encrypt(8).
zfs create [-p] [-o property=value] ... filesystem
Creates a new ZFS file system. The file system is automatically
mounted according to the mountpoint property inherited from the
parent.
-p
Creates all the non-existing parent datasets. Datasets created
in this manner are automatically mounted according to the
mountpoint property inherited from their parent. Any property
specified on the command line using the -o option is ignored.
If the target filesystem already exists, the operation com‐
pletes successfully.
-o property=value
Sets the specified property as if the command zfs set prop‐
erty=value was invoked at the same time the dataset was cre‐
ated. Any editable ZFS property can also be set at creation
time. Multiple -o options can be specified. An error results if
the same property is specified in multiple -o options.
zfs create [-ps] [-b blocksize] [-o property=value] ... -V size volume
Creates a volume of the given size. The volume is exported as a
block device in /dev/zvol/{dsk,rdsk}/path, where path is the name
of the volume in the ZFS namespace. The size represents the logical
size as exported by the device. By default, a reservation of equal
size is created.
size is automatically rounded up to the nearest 128 KB to ensure
that the volume has an integral number of blocks regardless of
blocksize.
-p
Creates all the non-existing parent datasets. Datasets created
in this manner are automatically mounted according to the
mountpoint property inherited from their parent. Any property
specified on the command line using the -o option is ignored.
If the target filesystem already exists, the operation com‐
pletes successfully.
-s
Creates a sparse volume with no reservation. See volsize in the
Native Properties section for more information about sparse
volumes.
-o property=value
Sets the specified property as if the zfs set property=value
command was invoked at the same time the dataset was created.
Any editable ZFS property can also be set at creation time.
Multiple -o options can be specified. An error results if the
same property is specified in multiple -o options.
-b blocksize
Equivalent to -o volblocksize=blocksize. If this option is
specified in conjunction with -o volblocksize, the resulting
behavior is undefined.
zfs destroy [-rRsf] filesystem|volume
Destroys the given dataset and all of its snapshots. 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). The default behavior is to asynchronously reclaim the
space occupied by the dataset after control returns to the caller.
The progress of asynchronous dataset destroys can be seen by using
the zpool monitor command. For more information, see the zpool(8)
man page.
-r
Recursively destroy all children.
-R
Recursively destroy all dependents, including cloned file sys‐
tems outside the target hierarchy.
-s
Destroys the snapshots synchronously. The default is to asyn‐
chronously reclaim destroyed datasets after the command returns
to the caller. If this option is specified, control does not
return to the caller until the blocks occupied by the datasets
are fully freed.
-f
Force an unmount of any file systems using the unmount -f com‐
mand. This option has no effect on non-file systems or
unmounted file systems.
Extreme care should be taken when applying either the -r or the -f
options, as they can destroy large portions of a pool and cause
unexpected behavior for mounted file systems in use.
zfs destroy [-rRsd] snapshot
The given snapshot is destroyed immediately if and only if the zfs
destroy command without the -d option would have destroyed it. Such
immediate destruction would occur, for example, if the snapshot had
no clones and the user-initiated reference count were zero.
If the snapshot does not qualify for immediate destruction, it is
marked for deferred deletion. 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.
-d
Defer snapshot deletion.
-r
Destroy (or mark for deferred deletion) all snapshots with this
name in descendent file systems.
-R
Recursively destroy all dependents.
-s
Destroys the snapshots synchronously. The default is to asyn‐
chronously reclaim destroyed datasets after the command returns
to the caller. If this option is specified, control does not
return to the caller until the blocks occupied by the datasets
are fully freed.
zfs destroy [share
The specified file system share is destroyed.
zfs diff [-FHNqrte] [-o field] ... snapshot [snapshot | filesystem]
zfs diff -E [-FHNqrt] [-o field] ... snapshot | filesystem
Gives a high-level description of the differences between a snap‐
shot and a descendent dataset. The descendent can be either a snap‐
shot of the dataset or the current dataset.
If a single snapshot is specified, then differences between that
snapshot and the current dataset are given.
For each file that has undergone a change between the original
snapshot and the descendent, the type of change is described along
with the name of the file. In the case of a rename, both the old
and new names are shown. Whitespace characters, backslash charac‐
ters, and other non-printable or non-7-bit ASCII characters found
in file names are displayed as a backslash character followed by
the three-digit octal representation of the byte value.
If the -t option is specified, the first column of output from the
command is the file's st_ctim value. For deleted files, this is the
final st_ctim in the earlier snapshot.
The type of change follows any timestamp displayed, and is
described with a single character:
+ Indicates the file was added in the later dataset.
- Indicates the file was removed in the later dataset.
M Indicates the file was modified in the later dataset.
R Indicates the file was renamed in the later dataset.
If the -F option is specified, the next column of output is a sin‐
gle character describing the type of the file. The mappings are:
F Regular file
/ Directory
B Block device
> Door
| FIFO
@ Symbolic link
P Event portal
= Socket
If the modification involved a change in the link count of a non-
directory file, the change is expressed as a delta within parenthe‐
ses on the modification line. If the file was renamed, the old name
is separated from the new with the string ->.
If the -H option is selected, easier-to-parse output is produced.
Fields are separated by a single tab, and no arrow string (->) is
placed between the old and new names of a rename. No guarantees are
made on the spacing between fields of non -H output.
If the -e option is selected, then all files added or modified
between the two snapshots are enumerated and no deleted files are
displayed. The change type always reports as + regardless of the
type of modification.
If the -E option is selected, then differences are given as if from
an empty snapshot to the specified snapshot or dataset.
If the -r option is selected, the differences between the dataset
and all the children datasets are displayed recursively. If a snap‐
shot is given as a parameter, that snapshot name must exist for all
the children datasets. Otherwise, warnings will be issued for
datasets not containing the snapshot. If the -q option is also
selected, these warnings will be silenced.
If the -N option is selected with -r, then all the new child
datasets added to the current dataset will be enumerated, along
with the differences among the existing datasets.
If the -o field option is selected then only selected fields are
displayed. Each line starts with the standard fields requested by
the -F and -t options, followed by the fields requested in succes‐
sive -o options. As with the -H option, all fields are separated by
a single tab. The allowable field names include:
object The number printed by ls -i for the file
parent The number printed by ls -i for enclosing direc‐
tory of the file
size The file size as displayed by ls -s
links The number of links to the file
linkschange The change in the number of links to the file
name The name of the file
oldname The name of the file before the rename, or ‐
(hyphen) if the file was not renamed
user The owner name of the file as displayed by ls
group The group name of the file as displayed by ls
ctime Timestamp when the file's metadata was last modi‐
fied
mtime Timestamp when the file was last modified
atime Timestamp when a file was last accessed
crtime Timestamp when a file was created
mountpoint Show the mountpoint name.
dataset_name Show the dataset name.
You must be granted the diff permission with zfs allow to use this
subcommand, unless you already have the {PRIV_SYS_CONFIG} or
{PRIV_SYS_MOUNT} privilege.
zfs get [-rHpe|-d max] [-o all | field[,...]] [-s source[,...]] [-I
state,...] all | property[,...] filesystem|volume|snapshot|share ...
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:
name Dataset name
property Property name
value Property value
source Property source. Can either be local, default,
temporary, inherited, or none (-).
All columns except the RECEIVED column are displayed by default;
specify particular or all columns, using the -o option. This com‐
mand takes a comma-separated list of properties as described in the
"Native Properties" and "User Properties" sections.
The special value all can be used to display all properties that
apply to the given dataset's type (filesystem, volume, or snap‐
shot).
-r
Recursively display properties for any children.
-H
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.
-p
Displays numbers in parseable (exact) values.
-e
Expands property sublists to any depth.
-d max
Recursively displays any children of the dataset, limiting the
recursion to depth. A depth of 1 will display only the dataset
and its direct children.
-o field
Set of fields to display. One or more of:
name,property,value,received,source
Present multiple fields as a comma-separated list. The default
value is:
name,property,value,source
The keyword all specifies all sources.
-s source
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:
local,default,inherited,temporary,received,none
The default value is all sources.
-I state
A comma-separated list of dataset states to display instead of
the 'normal' datasets that are usually displayed. The state
parameter can include the following non-normal states: receiv‐
ing, resumable, hidden, or all. For instance, specifying -I
resumable will display only resumable datasets. The state value
'all' will display datasets with receiving, resumable or hidden
states.
zfs groupspace [-hniHp] [-o field[,...]] [-sS field]... [-t type
[,...]] filesystem | snapshot
Displays space consumed by, and quotas on, each group in the speci‐
fied filesystem or snapshot. This subcommand is identical to zfs
userspace, except that the default types to display are -t posix‐
group,smbgroup.
-
zfs hold [-r] tag snapshot ...
Adds a single reference, named with the tag argument, to the speci‐
fied snapshot or snapshots. Each snapshot has its own tag names‐
pace, and tags must be unique within that space.
If a hold exists on a snapshot, attempts to destroy that snapshot
by using the zfs destroy command return EBUSY.
-r
Specifies that a hold with the given tag is applied recursively
to the snapshots of all descendent file systems.
zfs holds [-r] snapshot ...
Lists all existing user references for the given snapshot or snap‐
shots.
-r
Lists the holds that are set on the named descendent snapshots,
in addition to listing the holds on the named snapshot.
zfs inherit [-rS] property filesystem|volume|snapshot|share ...
Clears the specified property, causing it to be inherited from an
ancestor. If no ancestor has the property set, then the default
value is used. See the "Properties" section for a listing of
default values, and details on which properties can be inherited.
-r
Recursively inherits the given property for all children.
-S
Reverts to the received property value, if any. If the property
does not have a received value, the behavior of zfs inherit -S
is the same as zfs inherit without -S. If the property does
have a received value, zfs inherit masks the received value
with the inherited value until zfs inherit -S reverts to the
received value.
zfs key -l | {-a | [-r] filesystem|volume}
zfs key -u [-f] | {-a | [-r] filesystem | volume
zfs key -c [-o keysource=value] {-a | [-r] filesystem|volume}
zfs key -K {-a | [-r] filesystem|volume}
For a full description of the zfs key syntax and examples, see
zfs_encrypt(8).
zfs list [-rH|-d max] [-o property[,...]] [ -t type[,...]] [-I
state,...][ -s property ] ... [ -S property ] ... [filesystem|vol‐
ume|snapshot|share|path] ...
Lists the property information for the given datasets in tabular
form. If specified, you can list property information by the abso‐
lute pathname or the relative pathname. By default, all file sys‐
tems and volumes are displayed. Snapshots are displayed if the
listsnaps property is on. The default is off. Shares are displayed
if the listshares property is on. The following fields are dis‐
played: name, used, available, referenced, mountpoint.
-H
Used for scripting mode. Do not print headers and separate
fields by a single tab instead of arbitrary white space.
-r
Recursively displays any children of the dataset on the command
line.
-d depth
Recursively displays any children of the dataset, limiting the
recursion to maximum depth. A depth of 1 will display only the
dataset and its direct children.
-o property
A comma-separated list of properties to display. The property
must be:
o One of the properties described in the "Native Prop‐
erties" section
o A user property
o The value name to display the dataset name
o The value space to display space usage properties on
file systems and volumes. This is a shortcut for
specifying -o name,avail,used,usedsnap,usedds,use‐
drefreserv,usedchild -t filesystem,volume syntax.
-s property
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 name to sort by the dataset name. Multiple prop‐
erties can be specified at one time using multiple -s property
options. Multiple -s options are evaluated from left to right
in decreasing order of importance.
The following is a list of sorting criteria:
o Numeric types sort in numeric order.
o String types sort in alphabetical order.
o Types inappropriate for a row sort that row to the
literal bottom, regardless of the specified order‐
ing.
o If no sorting options are specified the existing
behavior of zfs list is preserved.
-S property
Same as the -s option, but sorts by property in descending
order.
-t type
A comma-separated list of types to display, where type is one
of filesystem, snapshot, volume, share, or all. For example,
specifying -t snapshot displays only snapshots. The following
aliases can be used in place of the type specifiers: fs
(filesystem), snap (snapshot), and vol (volume).
-I state
A comma-separated list of dataset states to display instead of
the 'normal' datasets that are usually displayed. The state
parameter can include the following non-normal states: receiv‐
ing, resumable, hidden, or all. For instance, specifying -I
resumable will display only resumable datasets. The state value
'all' will list all datasets in states other than the 'normal'
state.
-p
Uses the exact (parseable) numeric output.
zfs mount
Displays all ZFS file systems currently mounted.
zfs mount [-vOS] [-o options] -a | filesystem
Mounts ZFS file systems. Invoked automatically as part of the boot
process.
-o options
An optional, comma-separated list of mount options to use tem‐
porarily for the duration of the mount. See the "Temporary
Mount Point Properties" section for details.
-O
Perform an overlay mount. See mount(8) for more information.
-v
Report mount progress.
-a
Mount all available ZFS file systems. Invoked automatically as
part of the boot process.
filesystem
Mount the specified filesystem.
A zfs mount operation for an encrypted dataset might prompt you
for a key, depending on the keysource property value. This
might occur, for example, if the keysource locator is set to
prompt.
zfs promote clone-filesystem
Promotes a clone file system to no longer be dependent on its ori‐
gin 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.
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 rename subcommand can be used to rename any
conflicting snapshots.
zfs receive [-vnFu] [[-o property=value] | [-x property]] ... filesys‐
tem|volume|snapshot
zfs receive [-vnFu] [[-o property=value] | [-x property]] ... [-d | -e]
filesystem
zfs receive -C <filesystem|volume>
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
zfs send subcommand, which by default creates a full stream. zfs
recv can be used as an alias for zfs receive.
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 ZFS volumes, the destination
device link is destroyed and re-created, which means the volume
cannot be accessed during the receive operation.
When a snapshot replication package stream that is generated by
using the zfs send -R command is received, any snapshots that do
not exist on the sending location are destroyed by using the zfs
destroy -d command. If -o property=value or -x property is speci‐
fied, it applies to the effective value of the property throughout
the entire subtree of replicated datasets. Effective property val‐
ues may be set or inherited, depending on the property and whether
the dataset is the topmost in the replicated subtree. Received
properties are retained in spite of being overridden and may be
restored with zfs inherit -rS or zfs send -Rb.
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 -d or -e option.
If the argument is a snapshot name, the specified snapshot is cre‐
ated. If the argument is a file system or volume name, a snapshot
with the same name as the sent snapshot is created within the spec‐
ified filesystem or volume. If the -d or -e option is specified,
the snapshot name is determined by appending the sent snapshot's
name to the specified filesystem. If the -d option is specified,
all but the pool name of the sent snapshot path is appended (for
example, b/c@1 appended from sent snapshot a/b/c@1), and if the -e
option is specified, only the tail of the sent snapshot path is
appended (for example, c@1 appended from sent snapshot a/b/c@1). In
the case of -d, any file systems needed to replicate the path of
the sent snapshot are created within the specified file system.
-d
Uses all but the first element of the sent snapshot path (all
but the pool name) to determine the name of the new snapshot as
described in the paragraph above.
-C
Write a receive checkpoint to stdout. A receive checkpoint is a
table of contents of snapshots already received.
-e
Uses the last element of the sent snapshot path to determine
the name of the new snapshot as described in the paragraph
above.
-F
Forces a rollback of the file system to the most recent snap‐
shot before performing the receive operation. If receiving an
incremental replication stream (for example, one generated by
zfs send -R -[iI]), destroy snapshots and file systems that do
not exist on the sending side.
-n
Do not actually receive the stream. This can be useful in con‐
junction with the -v option to verify the name the receive
operation would use.
Note that ZFS does not verify whether the file systems and
clones required by the stream exists. Therefore, actual receive
can fail due to unfulfilled stream dependencies even though the
simulated receive passed.
-o property=value
Sets the specified property as if the command zfs set prop‐
erty=value is invoked at the same time the received dataset is
created from the non-incremental send stream or updated from
the incremental send stream. Any editable ZFS property can also
be set at receive time. Set-once properties bound to the
received data, such as normalization and casesensitivity, can‐
not be set at receive time even when the datasets are newly
created by zfs receive. Multiple -o options can be specified.
An error results if the same property is specified in multiple
-o or -x options.
-u
File system that is associated with the received stream is not
mounted.
-v
Print verbose information about the stream and the time
required to perform the receive operation.
-x property
Ensures that the effective value of the specified property
after the receive is unaffected by the value of that property
in the send stream (if any), as if the property had been
excluded from the send stream. If the specified property is not
present in the send stream, this option does nothing. If a
received property needs to be overridden, the effective value
can be set or inherited, depending on the property. In the case
of an incremental update, -x leaves any existing local setting
or explicit inheritance unchanged (since the received property
is already overridden). All -o restrictions apply equally to
-x.
zfs release [-r] tag snapshot...
Removes a single reference, named with the tag argument, from the
specified snapshot or snapshots. The tag must already exist for
each snapshot.
If a hold exists on a snapshot, attempts to destroy that snapshot
by using the zfs destroy command return EBUSY.
-r
Recursively releases a hold with the given tag on the snapshots
of all descendent file systems.
zfs rename filesystem|volume|snapshot
filesystem|volume|snapshot
zfs rename [-p] filesystem|volume filesystem|volume
Renames the given dataset. The new target can be located anywhere
in the ZFS 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.
All child ZFS datasets must be unmounted before the parent ZFS
dataset can be renamed. If the child dataset cannot be unmounted,
zfs reports an error.
$ zfs rename rpool/parent rpool/renamed
cannot unmount '/rpool/child': Device busy
In such a situation, it is possible to rename the dataset with this
approach:
$ zfs snapshot rpool/parent@rename
$ zfs clone rpool/parent@rename rpool/renamed
$ zfs promote rpool/renamed
$ zfs destroy rpool/parent
$ zfs destroy rpool/renamed@rename
Note that all data written to rpool/parent after creating the
@rename snapshot will be lost.
Renaming root dataset is not allowed. The root dataset can only be
renamed by renaming the pool, which will rename the root dataset to
the new pool name. Use zpool export <pool> command and then zpool
import <pool> <newpoolname> command to rename the root dataset to
the new pool name.
-p
Creates all the non-existent parent datasets. Datasets created
in this manner are automatically mounted according to the
mountpoint property inherited from their parent.
zfs rename -r snapshot snapshot
Recursively renames the snapshots of all descendent datasets. Snap‐
shots are the only dataset that can be renamed recursively.
zfs rename share share
Renames the specified share to a new share name.
zfs rollback [-rRf] snapshot
Rolls 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 snap‐
shot other than the most recent one. In order to do so, all inter‐
mediate snapshots must be destroyed by specifying the -r option.
The -rR options do not recursively destroy the child snapshots of a
recursive snapshot. Only the top-level recursive snapshot is
destroyed by either of these options. To completely roll back a
recursive snapshot, you must rollback the individual child snap‐
shots.
-r
Recursively destroys any snapshots more recent than the one
specified.
-R
Recursively destroys any more recent snapshots, as well as any
clones of those snapshots.
-f
Used with the -R option to force an unmount of any clone file
systems that are to be destroyed.
zfs send [-vbpnC] [-[Rr[c]]] [-w compress|none] [-D [-m <memsize>]]
[-[iI] <snapshot>] [-s <subopt>] <snapshot>
Creates a stream representation of the second snapshot, which is
written to standard output. The output can be redirected to a file
or to a different system (for example, using ssh(1). By default, a
full stream is generated.
-b
Sends only received property values whether or not they are
overridden by local settings, but only if the dataset has ever
been received. Use this option when you want zfs receive to
restore received properties backed up on the sent dataset and
to avoid sending local settings that may have nothing to do
with the source dataset, but only with how the data is backed
up.
-c
Creates a self-contained stream. A self-contained stream is one
that is not dependent on any datasets not included in the
stream package. Valid with the -r and -R options. If used with
the -R option and if clones are present, no snapshot preceding
the clone origin will be included in the stream. If used with
the -i or -I option, the stream will be dependent on the snap‐
shot specified as an argument to the -i or -I option.
See Saving, Sending, and Receiving ZFS Data in Managing ZFS
File Systems in Oracle Solaris 11.4 for details.
-C
Read a receive checkpoint from stdin. A receive checkpoint is a
table of contents of snapshots that have been successfully
received and do not need to be sent again.
-D
Performs dedup processing on the stream. Deduplicated streams
cannot be received on systems that do not support the stream
deduplication feature.
See Saving, Sending, and Receiving ZFS Data in Managing ZFS
File Systems in Oracle Solaris 11.4 to understand how a repli‐
cation stream package differs from a recursive stream package.
-i snapshot
Generates an incremental stream from the first snapshot to the
second snapshot. The incremental source (the first snapshot)
can be specified as the last component of the snapshot name
(for example, the part after the @), and it is assumed to be
from the same file system as the second snapshot.
If the destination is a clone, the source may be the origin
snapshot, which must be fully specified (for example,
pool/fs@origin, not just @origin).
-I snapshot
Generates a stream package that sends all intermediary snap‐
shots from the first snapshot to the second snapshot. For exam‐
ple, -I @a fs@d is similar to -i @a fs@b; -i @b fs@c; -i @c
fs@d. The incremental source snapshot may be specified as with
the -i option.
-n
Do not actually send the stream. This option can also be used
with the -v option to see what snapshots would have been sent.
-p
Use the -p option to include properties in the send stream
without the -R option. For more information, see Applying Dif‐
ferent Property Values to a ZFS Snapshot Stream in Managing ZFS
File Systems in Oracle Solaris 11.4
-R
Generates a replication stream package that replicates the
specified file system, and all descendent file systems, up to
the named snapshot. When received, all properties, snapshots,
descendent file systems, and clones are preserved.
If the -i or -I flags are used in conjunction with the -R 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 -F flag is
specified when this stream is received, snapshots and file sys‐
tems that do not exist on the sending side are destroyed.
When combined with the -c option, a self-contained replication
stream package is created. If clones are present, no snapshot
preceding the clone origin will be included in the stream. If
both the -c and -I options are used, file systems and volumes
that do not have the snapshot specified with the -I option are
sent as self-contained streams.
-r
Generates a recursive stream package. A recursive stream pack‐
age contains a series of full and/or incremental streams. When
received, all properties and descendent file systems are pre‐
served. Unlike with the replication stream packages generated
with the -R flag, intermediate snapshots are not preserved
unless the intermediate snapshot is the origin of a clone that
is included in the stream.
If the -i option is used in conjunction with the -r option, an
incremental recursive stream is generated. The current values
of properties as well as current snapshot and file system names
are set when the stream is received. If the -F option is speci‐
fied when this stream is received, snapshots and file systems
that do not exist on the sending side are destroyed. The -I
option cannot be used in conjunction with the -r option.
When combined with the -c option, a self-contained recursive
stream package is created. If both the -c and -i options are
used, file systems and volumes that do not have the snapshot
specified with the -i option are sent as self-contained
streams.
See Saving, Sending, and Receiving ZFS Data in Managing ZFS
File Systems in Oracle Solaris 11.4 to understand how a recur‐
sive stream package differs from a replication stream package.
-s streamsize
The -s switch is used to specify a set of stream options that
modify the format of the stream or the operation of the send
command. Later options take precedence over earlier options.
Any option can be preceded by 'no' to turn the option off. For
example -s nocheck requests the use of a stream format without
per-record checksums.
Specifies that the size of the stream, in bytes, that will be
output to stderr. -v suppresses the -s streamsize option.
-s check
Specifies that the output stream will use a send stream format
that uses per-record checksums. This format is the system-wide
default. When an interrupted transfer is resumed by using a
receive checkpoint (see zfs send -C), the use of the 'check'
format before the outage enables the resumed transfer to pre‐
serve and reuse the portions of the interrupted snapshot that
were already successfully received.
-s nocheck
Specifies that the output stream will use a legacy send stream
format without per-record checksums. This format is suitable
for transmission to older systems that do not support the new
format.
-v
Displays verbose information about the stream package gener‐
ated.
-w
Specifies the compress argument. The compressed filesystem
blocks are sent compressed in the stream, that is, without
decompressing them. compress also implicitly enables the -p
option, and is mutually exclusive with the -D option.
The none argument disables the compress behaviour. none is the
default argument, when the -w option is not specified.
-m <memsize>
Limits the amount of memory used by deduplication processing to
the value specified in bytes, kbytes, mbytes, or gbytes by
using the appropriate suffix. For example, 2G, 2048M, 2097152K,
or 2147483648.
-s memsize
Specifies that the deduplication memory size, in bytes, will be
output to stderr. If both -s streamsize and -s memsize
options are specified, the values are output on successive
lines in the order specified on the command line. -s option is
incompatible with -v option.
The format of the stream is committed. You will be able to receive
your streams on future versions of ZFS.
The snapshot specified by the snapshot argument must exist. If the
-R or -r options are used then a recursive snapshot as specified by
the snapshot argument should exist and will be sent recursively.
There are two special cases. First, a descendant filesystem tree
that is completely missing the appropriate named snapshot will be
skipped and will not be included in the send stream. In this case,
a warning message will be printed for each snapshot that is
skipped. Second, if a descendant filesystem tree is of mixed status
(that is, the root of the descendant filesystem tree is missing the
requested snapshot but one or more of its child filesystems do have
the requested snapshot), then an error is generated to terminate
the send operation.
To send snapshots of multilevel filesystems, the user's process
clearance must dominate the label specified by the mlslabel prop‐
erty.
zfs set [-r] property=value filesystem|volume|snapshot ...
Sets the property to the given value for each dataset. Only some
properties can be edited. See the "Properties" section for more
information on what properties can be set and acceptable values.
Numeric values can be specified as exact values, or in a human-
readable form with a suffix of B, K, M, G, T, P, E, Z (for bytes,
kilobytes, megabytes, gigabytes, terabytes, petabytes, exabytes, or
zettabytes, respectively). User properties can be set on snapshots.
For more information, see the "User Properties" section.
-r
Recursively apply the effective value of the setting throughout
the subtree of child datasets. The effective value may be set
or inherited, depending on the property. Use the zfs help -l
properties command to review whether a property is settable or
inheritable.
zfs share [-u] -o property=value ... filesystem%share
zfs share filesystem|mountpoint|filesystem%share
zfs share -a | filesystem
For a full description of zfs share syntax and examples and setting
the share.nfs or share.smb property, see zfs_share(8).
zfs snapshot [-r] [-o property=value] ... filesystem@snapname|vol‐
ume@snapname
Creates a snapshot with the given name. All previous modifications
by successful system calls to the file system are part of the snap‐
shot. zfs snap can be used as an alias for zfs snapshot. See the
"Snapshots" section for details.
-r
Recursively creates snapshots of all descendent datasets. Snap‐
shots are taken atomically, so that all recursive snapshots
correspond to the same moment in time.
-o property=value
Sets the specified property; see zfs create for details.
zfs unallow [-rldug] everyone|user|group[,...] [perm|@setname[, ...]]
filesystem|volume
zfs unallow [-rld] -e [perm|@setname [,...]] filesystem|volume
zfs unallow [-r] -c [perm|@setname[,...]]
filesystem|volume
zfs unallow [-r] -s @setname [perm|@setname[,...]]
filesystem|volume
For a full description of the zfs unallow syntax and examples, see
zfs_allow(8).
zfs unmount [-f] -a | filesystem|mountpoint
Unmounts currently mounted ZFS file systems. Invoked automatically
as part of the shutdown process.
-f
Forcibly unmount the file system, even if it is currently in
use.
-a
Unmounts all available ZFS file systems. Invoked automatically
as part of the boot process.
filesystem|mountpoint
Unmounts the specified filesystem. The command can also be
given a path to a ZFS file system mount point on the system.
For an encrypted dataset, the key is not unloaded when the file
system is unmounted. To unload the key, see zfs key.
zfs unshare filesystem|mountpoint|filesystem%share
zfs unshare -a | -r filesystem
For a full description of zfs unshare syntax and examples, see
zfs_share(8).
zfs upgrade
Identifies a file system version, which determines available file
system features in the currently running software release. You can
continue to use older file system versions, but some features might
not be available. A file system can be upgraded by using the zfs
upgrade -a command. You will not be able to access a file system
of a later version on a system that runs an earlier software ver‐
sion.
zfs upgrade [-v]
Displays ZFS file system versions that are supported by the current
software. The current ZFS file system versions and all previously
supported versions are displayed, along with an explanation of the
features provided with each version.
zfs upgrade [-r] [-V version] [-a | filesystem]
Upgrades file systems to a new, on-disk version. Upgrading a file
system means that it will no longer be accessible on a system run‐
ning an older software version. A zfs send stream that is generated
from a new file system snapshot cannot be accessed on a system that
runs an older software version.
In general, the file system version is independent of the pool ver‐
sion. See zpool(8) for information on the zpool upgrade command.
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.
-a
Upgrades all file systems on all imported pools.
filesystem
Upgrades the specified file system.
-r
Upgrades the specified file system and all descendent file sys‐
tems.
-V version
Upgrades to the specified version. If the -V flag is not speci‐
fied, 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.
zfs userspace [-hniHp] [-o field[,...]] [-sS field]... [-t type [,...]]
filesystem | snapshot
Displays space consumed by, and quotas on, each user in the speci‐
fied filesystem or snapshot. This corresponds to the userused@user
and userquota@user properties.
-h
Displays syntax help message and exit.
-n
Prints numeric ID instead of user/group name.
-H
Does not print headers, use tab-delimited output.
-p
Uses exact (parseable) numeric output.
-o field[,...]
Displays only the specified fields from the following set,
type,name,used,quota. The default is to display all fields.
-s field
Sorts output by this field. The s and S flags may be specified
multiple times to sort first by one field, then by another. The
default is -s type -s name.
-S field
Sorts by this field in reverse order. See -s.
-t type[,...]
Prints only the specified types from the following set,
all,posixuser,smbuser,posixgroup,smbgroup.
The default is -t posixuser,smbuser
The default can be changed to include group types.
-i
Translates SID to POSIX ID. The POSIX ID may be ephemeral if no
mapping exists. Normal POSIX interfaces (for example, stat(2),
ls -l) perform this translation, so the -i option allows the
output from zfs userspace to be compared directly with those
utilities. However, -i may lead to confusion if some files were
created by an SMB user before a SMB-to-POSIX name mapping was
established. In such a case, some files are owned by the SMB
entity and some by the POSIX entity. However, the -i option
will report that the POSIX entity has the total usage and quota
for both.
EXAMPLES
Example 1 Creating a ZFS File System Hierarchy
The following commands create a file system named pool/home and a file
system named pool/home/bob. The mount point /export/home is set for the
parent file system, and is automatically inherited by the child file
system.
# zfs create pool/home
# zfs set mountpoint=/export/home pool/home
# zfs create pool/home/bob
Example 2 Creating a ZFS Snapshot
The following command creates a snapshot named yesterday. This snapshot
is mounted on demand in the .zfs/snapshot directory at the root of the
pool/home/bob file system.
# zfs snapshot pool/home/bob@yesterday
Example 3 Creating and Destroying Multiple Snapshots
The following command creates snapshots named yesterday of pool/home
and all of its descendent file systems. Each snapshot is mounted on
demand in the .zfs/snapshot directory at the root of its file system.
The second command destroys the newly created snapshots.
# zfs snapshot -r pool/home@yesterday
# zfs destroy -r pool/home@yesterday
Example 4 Disabling and Enabling File System Compression
The following command disables the compression property for all file
systems under pool/home. The next command explicitly enables compres‐
sion for pool/home/anne.
# zfs set compression=off pool/home
# zfs set compression=on pool/home/anne
Example 5 Listing ZFS Datasets
The following command lists all active file systems and volumes in the
system. Snapshots are displayed if the listsnaps property is on. The
default is off. Shares are displayed if the listshares property is on.
See zpool(8) for more information on pool properties.
# zfs list
NAME USED AVAIL REFER MOUNTPOINT
pool 450K 457G 18K /pool
pool/home 315K 457G 21K /export/home
pool/home/anne 18K 457G 18K /export/home/anne
pool/home/bob 276K 457G 276K /export/home/bob
Example 6 Setting a Quota on a ZFS File System
The following command sets a quota of 30 GB for pool/home/bob.
# zfs set quota=30G pool/home/bob
Example 7 Listing ZFS Properties
The following command lists all properties for pool/home/bob.
# zfs get all pool/home/bob
NAME PROPERTY VALUE SOURCE
pool/home/bob aclinherit restricted default
pool/home/bob aclmode discard default
pool/home/bob atime on default
pool/home/bob available 30.0G -
pool/home/bob canmount on default
pool/home/bob casesensitivity mixed -
pool/home/bob checksum on default
pool/home/bob compression on local
pool/home/bob compressratio 1.00x -
pool/home/bob copies 1 default
pool/home/bob creation Tue Jul 3 10:39 2012 -
pool/home/bob dedup off default
pool/home/bob devices on default
pool/home/bob encryption off -
pool/home/bob exec on default
pool/home/bob keychangedate - default
pool/home/bob keysource none default
pool/home/bob keystatus none -
pool/home/bob logbias latency default
pool/home/bob mlslabel none -
pool/home/bob mounted yes -
pool/home/bob mountpoint /pool/home/bob default
pool/home/bob multilevel off -
pool/home/bob nbmand off default
pool/home/bob normalization none -
pool/home/bob primarycache all default
pool/home/bob quota 30G local
pool/home/bob readonly off default
pool/home/bob recordsize 128K default
pool/home/bob referenced 31K -
pool/home/bob refquota none default
pool/home/bob refreservation none default
pool/home/bob rekeydate - default
pool/home/bob reservation none default
pool/home/bob rstchown on default
pool/home/bob secondarycache all default
pool/home/bob setuid on default
pool/home/bob shadow none -
pool/home/bob share.* ... inherited
pool/home/bob snapdir hidden default
pool/home/bob sync standard default
pool/home/bob type filesystem -
pool/home/bob used 31K -
pool/home/bob usedbychildren 0 -
pool/home/bob usedbydataset 31K -
pool/home/bob usedbyrefreservation 0 -
pool/home/bob usedbysnapshots 0 -
pool/home/bob utf8only off -
pool/home/bob version 6 -
pool/home/bob vscan off default
pool/home/bob xattr on default
pool/home/bob zoned off default
The following command gets a single property value.
# zfs get -H -o value compression pool/home/bob
on
The following command lists all properties with local settings for
pool/home/bob.
# zfs get -r -s local -o name,property,value all pool/home/bob
NAME PROPERTY VALUE
pool/home/bob compression on
pool/home/bob quota 30G
Example 8 Rolling Back a ZFS File System
The following command reverts the contents of pool/home/anne to the
snapshot named yesterday, deleting all intermediate snapshots.
# zfs rollback -r pool/home/anne@yesterday
Example 9 Creating a ZFS Clone
The following command creates a writable file system whose initial con‐
tents are the same as pool/home/bob@yesterday.
# zfs clone pool/home/bob@yesterday pool/clone
Example 10 Promoting a ZFS Clone
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:
# zfs create pool/project/production
populate /pool/project/production with data
# zfs snapshot pool/project/production@today
# zfs clone pool/project/production@today pool/project/beta
make changes to /pool/project/beta and test them
# zfs promote pool/project/beta
# zfs rename pool/project/production pool/project/legacy
# zfs rename pool/project/beta pool/project/production
once the legacy version is no longer needed, it can be destroyed
# zfs destroy pool/project/legacy
Example 11 Inheriting ZFS Properties
The following command causes pool/home/bob and pool/home/anne to
inherit the checksum property from their parent.
# zfs inherit checksum pool/home/bob pool/home/anne
Example 12 Remotely Replicating ZFS Data
The following commands send a full stream and then an incremental
stream to a remote machine, restoring them into poolB/received/fs@a and
poolB/received/fs@b, respectively. poolB must contain the file system
poolB/received, and must not initially contain poolB/received/fs.
# zfs send pool/fs@a | \
ssh host zfs receive poolB/received/fs@a
# zfs send -i a pool/fs@b | ssh host \
zfs receive poolB/received/fs
The above syntax assumes that sshd has been configured to allow remote
root access.
Example 13 Using the zfs receive -d Option
The following command sends a full stream of poolA/fsA/fsB@snap to a
remote machine, receiving it into poolB/received/fsA/fsB@snap. The
fsA/fsB@snap portion of the received snapshot's name is determined from
the name of the sent snapshot. poolB must contain the file system
poolB/received. If poolB/received/fsA does not exist, it is created as
an empty file system.
# zfs send poolA/fsA/fsB@snap | \
ssh host zfs receive -d poolB/received
Example 14 Setting User Properties
The following example sets the user-defined com.example:department
property for a dataset.
# zfs set com.example:department=12345 tank/accounting
Example 15 Performing a Rolling Snapshot
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:
# zfs destroy -r pool/users@7daysago
# zfs rename -r pool/users@6daysago @7daysago
# zfs rename -r pool/users@5daysago @6daysago
# zfs rename -r pool/users@4daysago @5daysago
# zfs rename -r pool/users@3daysago @4daysago
# zfs rename -r pool/users@2daysago @3daysago
# zfs rename -r pool/users@yesterday @2daysago
# zfs rename -r pool/users@today @yesterday
# zfs snapshot -r pool/users@today
Example 16 Displaying ZFS Snapshot Differences
The following example is output of the zfs diff -F and -t options
specified:
# zfs diff -Ft myfiles@snap1
1269962501.206726811 M / /myfiles/
1269962444.207369955 M F /myfiles/link_to_me (+1)
1269962499.207519034 R /myfiles/rename_me -> /myfiles/renamed
1269962431.813566720 - F /myfiles/delete_me
1269962518.666905544 + F /myfiles/new_file
1269962501.393099817 + | /myfiles/new_pipe
Example 17 Resuming an Interrupted Send/Receive
Request that the dataset hierarchy at dst/fs on system target be made
to match the source hierarchy src/fs as of the recursive snapshot
@TOSNAP:
# zfs send -R src/fs@TOSNAP | \
ssh target zfs receive -F dst/fs
If the above command is interrupted, request the transfer be resumed
where it left off:
# ssh target zfs receive -C dst/fs | \
zfs send -RC src@TOSNAP | \
ssh target zfs receive -F dst/fs
Similarly, to request that a dataset hierarchy dst/fs on system target
that already matches the source hierarchy as of recursive snapshot
@FROMSNAP now be incrementally updated to match the new source recur‐
sive snapshot @TOSNAP:
# zfs send -R -I src/fs@FROMSNAP src/fs@TOSNAP | \
ssh target zfs receive -F dst/fs
If the above incremental update is interrupted, request the transfer be
resumed where it left off:
# ssh target zfs receive -C dst/fs | \
zfs send -RC -I src/fs@FROMSNAP src/fs@TOSNAP | \
ssh target zfs receive -F dst/fs
Example 18 Display Incomplete Datasets
# zfs list -I all tank/dest
NAME USED AVAIL REFER TYPE STATE
tank/dest/one/%now 521M 120G 521M volume receiving
tank/dest/two 33.8M 120G 33.8M filesystem resumable
Example 19 Destroy Resumable Datasets
Resumable datasets that will never be resumed can be destroyed to
release space. Care should be taken to make sure the correct datasets
are listed and that the incompletely received data will never be
resumed. Then the following command will remove the resumable datasets:
# zfs list -HI resumable -o name tank/dest | \
xargs -i -n1 zfs destroy "{}"
EXIT STATUS
The following exit values are returned:
0
Successful completion.
1
An error occurred.
2
Invalid command line options were specified.
3
A fatal error occurred.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) ATTRIBUTE TYPEAT‐
TRIBUTE VALUE _ Availabilitysystem/file-system/zfs _ Interface Stabili‐
tyCommitted
SEE ALSO
chmod(1), chown(1), gzip(1), pktool(1), setlabel(1), ssh(1), chmod(2),
chown(2), stat(2), write(2), fsync(3C), setflabel(3TSOL), dfstab(5),
vfstab(5), attributes(7), datasets(7), filesystem(7), mount(8), shad‐
owd(8), share(8), share_nfs(8), share_smb(8), unshare(8), zfs_allow(8),
zfs_encrypt(8), zfs_share(8), zonecfg(8), zpool(8)
For information about other ZFS features, see zfs_allow(8),
zfs_encrypt(8), zfs_share(8), and the Managing ZFS File Systems in Ora‐
cle Solaris 11.4 book.
NOTES
A file described as modified by the diff subcommand might have been
modified in multiple ways. Any action that causes a change in the
st_ctim (see stat(2)) is a basis for reporting a modification.
Oracle Solaris 11.4 23 Sep 2021 zfs(8)