Man:zfs

Материал из Xgu.ru

Перейти к: навигация, поиск
stub.png
Данная страница находится в разработке.
Эта страница ещё не закончена. Информация, представленная здесь, может оказаться неполной или неверной.

Если вы считаете, что её стоило бы доработать как можно быстрее, пожалуйста, скажите об этом.

Оригинал: http://www.freebsd.org/cgi/man.cgi?query=zfs&apropos=0&sektion=0&manpath=FreeBSD+7.0-RELEASE&format=html


zfs(1M) 		System Administration Commands		       zfs(1M)

NAME
       zfs - configures ZFS file systems

SYNOPSIS
       zfs [-?]

       zfs create [[-o property=value]]... filesystem

       zfs create [-s] [-b blocksize] [[-o property=value]]... -V size volume

       zfs destroy [-rRf] filesystem|volume|snapshot

       zfs clone snapshot filesystem|volume

       zfs promote filesystem

       zfs rename filesystem|volume|snapshot
	   [filesystem|volume|snapshot]

       zfs snapshot [-r] filesystem@name|volume@name

       zfs rollback [-rRf] snapshot

       zfs list [-rH] [-o prop[,prop] ]... [ -t type[,type]...]
	   [ -s prop [-s prop]... [ -S prop [-S prop]...
	   [filesystem|volume|snapshot|/pathname|./pathname ...

       zfs set property=value filesystem|volume ...

       zfs get [-rHp] [-o field[,field]...]
	   [-s source[,source]...] all | property[,property]...
	    filesystem|volume|snapshot ...

       zfs inherit [-r] property filesystem|volume... ...

       zfs mount

       zfs mount [-o options] [-O] -a

       zfs mount [-o options] [-O] filesystem

       zfs unmount [-f] -a

       zfs unmount [-f] filesystem|mountpoint

       zfs share -a

       zfs share filesystem

       zfs unshare [-f] -a

       zfs unshare [-f] filesystem|mountpoint

       zfs send [-i snapshot1] snapshot2

       zfs receive [-vnF ] filesystem|volume|snapshot

       zfs receive [-vnF ] -d filesystem

       zfs jail jailid filesystem

       zfs unjail jailid filesystem

DESCRIPTION
       The  zfs  command configures ZFS datasets within a ZFS storage pool, as
       described in zpool(1M). 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  standard  POSIX  file system. ZFS file systems can be
		      mounted within the standard file	system	namespace  and
		      behave like any other file system.

       volume	      A logical volume exported as a raw or block device. This
		      type of dataset should only be used under  special  cir-
		      cumstances.  File  systems  are  typically  used in most
		      environments. Volumes cannot be  used  in  a  non-global
		      zone.

       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(1M) command.

       See zpool(1M) 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"	direc-
       tory  in  the  root  of	the  file  system. Snapshots are automatically
       mounted on demand and may be unmounted at regular intervals. The  visi-
       bility of the ".zfs" directory can be controlled by the "snapdir" prop-
       erty.

   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  will  likely  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
       editing	/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	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
       administrator  is responsible for mounting and unmounting the file sys-
       tem.

   Zones
       A ZFS file system can be added to a non-global zone by using  zonecfg's
       "add  fs"  subcommand.  A ZFS file system that is added to a non-global
       zone must have its mountpoint property set to legacy.

       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 zonecfg's
       "add dataset" subcommand. You cannot delegate a dataset to one zone and
       the  children of the same dataset to another zone. The zone administra-
       tor can change properties of the dataset or any of its  children.  How-
       ever, the "quota" property is controlled by the global administrator.

       A  ZFS  volume  can  be added as a device to a non-global zone by using
       zonecfg's "add device" subcommand. However, its physical properties can
       only be modified by the global administrator.

       For more information about zonecfg syntax, see zonecfg(1M).

       After a dataset is delegated to a non-global zone, the "zoned" property
       is automatically set. A zoned file system  cannot  be  mounted  in  the
       global  zone,  since the zone administrator might have to set the mount
       point to an unacceptable value.

       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.

   Native Properties
       Properties  are	divided  into  two  types,  native properties and user
       defined properties. Native properties either export 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  properties,  see
       the "User Properties" section.

       Every  dataset has a set of properties that export statistics about the
       dataset as well as control various behavior. Properties	are  inherited
       from the parent unless overridden by the child. Snapshot properties can
       not be edited; they always inherit their inheritable properties.  Prop-
       erties that are not applicable to snapshots are not displayed.

       The  values  of numeric properties can be specified using the following
       human-readable suffixes (for example, "k", "KB", "M", "Gb", etc, up  to
       Z  for  zettabyte).  The following are all valid (and equal) specifica-
       tions:

	 "1536M", "1.5g", "1.50GB".

       The values of non-numeric properties are case  sensitive  and  must  be
       lowercase, except for "mountpoint" and "sharenfs".

       The  first  set of properties consist of read-only statistics about the
       dataset. These properties cannot be set, nor are they inherited. Native
       properties apply to all dataset types unless otherwise noted.

       type		The  type  of  dataset: "filesystem", "volume", "snap-
			shot", or "clone".

       creation 	The time this dataset was created.

       used		The amount of space consumed by this dataset  and  all
			its  descendants.  This  is  the value that is checked
			against this  dataset's  quota	and  reservation.  The
			space  used  does  not include this dataset's reserva-
			tion, but does take into account the  reservations  of
			any  descendant  datasets.  The amount of space that a
			dataset consumes from  its  parent,  as  well  as  the
			amount	of space that will be freed if this dataset is
			recursively destroyed, is the  greater	of  its  space
			used and its reservation.

			When  snapshots (see the "Snapshots" section) are cre-
			ated, their space  is  initially  shared  between  the
			snapshot and the file system, and possibly with previ-
			ous snapshots. As the file system changes, space  that
			was  previously shared becomes unique to the snapshot,
			and counted in the snapshot's  space  used.  Addition-
			ally,  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  sec-
			onds. Committing a change to a disk using fsync(3c) or
			O_SYNC does not necessarily guarantee that  the  space
			usage information is updated immediately.

       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".

       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 ini-
			tially references the same amount of space as the file
			system or snapshot it was created from, since its con-
			tents are identical.

			This property can also be referred to by its shortened
			column name, "refer".

       compressratio	The  compression  ratio  achieved  for	this  dataset,
			expressed as a multiplier. Compression can  be	turned
			on  by	running  "zfs set compression=on dataset". The
			default value is "off".

       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.

       The  following  two  properties	can be set to control the way space is
       allocated between datasets. These properties are not inherited, but  do
       affect their descendants.

       quota=size | none

	   Limits  the	amount of space a dataset and its descendants can con-
	   sume. This property enforces a hard limit on the  amount  of  space
	   used.  This	includes  all space consumed by descendants, including
	   file systems and snapshots. Setting a quota on a  descendant  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.

       reservation=size | none

	   The minimum amount of space guaranteed to a dataset and its descen-
	   dants. 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".

       volsize=size

	   For	volumes, specifies the logical size of the volume. By default,
	   creating a volume establishes a  reservation  of  equal  size.  Any
	   changes  to	volsize  are  reflected in an equivalent change to the
	   reservation. The volsize can only be set to a multiple of volblock-
	   size, and cannot be zero.

	   The	reservation is kept equal to the volume's logical size to pre-
	   vent unexpected behavior for consumers.  Without  the  reservation,
	   the	volume could run out of space, resulting in undefined behavior
	   or data corruption, depending on how  the  volume  is  used.  These
	   effects  can also occur when the volume size is changed while it is
	   in use (particularly when shrinking the size). Extreme care	should
	   be used when adjusting the volume size.

	   Though not recommended, a "sparse volume" (also known as "thin pro-
	   visioning") can be created by specifying the -s option to the  "zfs
	   create -V" command, or by changing the reservation after the volume
	   has been created.  A "sparse volume" is a volume where the reserva-
	   tion is less then the volume size. Consequently, writes to a sparse
	   volume 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.

       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
	   Kbytes. Any power of 2 from 512 bytes to 128 Kbytes is valid.

	   This property can also be referred to by its shortened column name,
	   "volblock".

       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  data-
	   base can result in significant performance gains. Use of this prop-
	   erty for general purpose file systems is strongly discouraged,  and
	   may adversely affect performance.

	   The	size specified must be a power of two greater than or equal to
	   512 and less than or equal to 128 Kbytes.

	   Changing the file system's recordsize only  affects	files  created
	   afterward; existing files are unaffected.

	   This property can also be referred to by its shortened column name,
	   "recsize".

       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.	Other-
	   wise,  they	are automatically remounted in the new location if the
	   property was previously "legacy" or "none", or if they were mounted
	   before  the property was changed. In addition, any shared file sys-
	   tems are unshared and shared in the new location.

       sharenfs=on | off | opts

	   Controls whether the file  system  is  shared  via  NFS,  and  what
	   options  are  used. A file system with a sharenfs property of "off"
	   is  managed	through   traditional	tools	such   as   share(1M),
	   unshare(1M), and dfstab(4). Otherwise, the file system is automati-
	   cally shared and unshared with the "zfs share"  and	"zfs  unshare"
	   commands.  If the property is set to "on", the share(1M) command is
	   invoked with  no  options.  Otherwise,  the	share(1M)  command  is
	   invoked with options equivalent to the contents of this property.

	   When  the "sharenfs" property is changed for a dataset, the dataset
	   and any children inheriting the property are re-shared with the new
	   options, only if the property was previously "off", or if they were
	   shared before the property was changed.  If	the  new  property  is
	   "off", the file systems are unshared.

       shareiscsi=on | off

	   Like  the "sharenfs" property, "shareiscsi" indicates whether a ZFS
	   volume is exported as an iSCSI target. The  acceptable  values  for
	   this  property are "on", "off", and "type=disk".  The default value
	   is "off". In the future, other target types might be supported. For
	   example, "tape".

	   You might want to set "shareiscsi=on" for a file system so that all
	   ZFS volumes within the file system are shared by  default.  Setting
	   this property on a file system has no direct effect, however.

       checksum=on | off | fletcher2, | fletcher4 | sha256

	   Controls  the  checksum  used to verify data integrity. The default
	   value is "on", which automatically selects an appropriate algorithm
	   (currently, fletcher2, but this may change in future releases). The
	   value "off" disables integrity checking  on	user  data.  Disabling
	   checksums is NOT a recommended practice.

       compression=on | off | lzjb | gzip | gzip-N

	   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)).

	   This  property can also be referred to by its shortened column name
	   "compress".

       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".

       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".

       setuid=on | off

	   Controls whether the set-UID bit is respected for the file  system.
	   The default value is "on".

       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".

       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".

       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".

       aclmode=discard | groupmask | passthrough

	   Controls how an ACL is modified during chmod(2). A file system with
	   an "aclmode" property of "discard" deletes all ACL entries that  do
	   not	represent  the	mode  of  the  file.  An "aclmode" property of
	   "groupmask" (the default) reduces user or  group  permissions.  The
	   permissions	are  reduced,  such  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 per-
	   mission   bits.  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.

       aclinherit=discard | noallow | secure | passthrough

	   Controls how ACL entries are inherited when files  and  directories
	   are	created.  A file system with an "aclinherit" property of "dis-
	   card" 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
	   "secure"  (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 inherita-
	   ble ACL entries without any modifications made to the  ACL  entries
	   when they are inherited.

       canmount=on | off

	   If  this  property  is  set	to  "off",  the  file system cannot be
	   mounted, and is ignored by "zfs mount -a". This is similar to  set-
	   ting  the  "mountpoint" property to "none", except that the dataset
	   still has a normal "mountpoint" property which  can	be  inherited.
	   This  allows  datasets  to be used solely as a mechanism to inherit
	   properties. One use case is to have two logically separate datasets
	   have  the  same  mountpoint,  so that the children of both datasets
	   appear in the same directory,  but  may  have  different  inherited
	   characteristics. The default value is "on".

	   This property is not inherited.

       xattr=on | off

	   Controls whether extended attributes are enabled for this file sys-
	   tem. The default value is "on".

       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"
	   property 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=" option.

       jailed=on | off

	   Controls  whether  the  dataset  is managed from within a jail. The
	   default value is "off".

   iscsioptions
       This read-only property, which is hidden, is used by the  iSCSI	target
       daemon  to  store persistent information, such as the IQN. It cannot be
       viewed or modified using the zfs command. The contents are not intended
       for external consumers.

   Temporary Mount Point Properties
       When  a	file  system  is  mounted, either through mount(1M) for legacy
       mounts or the "zfs mount" command for normal file  systems,  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
	     exec		     exec/noexec
	     readonly		     ro/rw
	     setuid		     setuid/nosetuid
	     xattr		     xattr/noxattr

       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.

   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.

       User property names must contain a colon (":")  character,  to  distin-
       guish  them  from  native properties. They might contain lowercase let-
       ters, numbers, 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  "mod-
       ule: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.  Property
       names  beginning  with "com.sun." are reserved for use by Sun Microsys-
       tems.

       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",  etc.)  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.

   Volumes as Swap or Dump Devices
       To set up a swap area, create a ZFS volume of a specific size and  then
       enable swap on that device. For more information, see the EXAMPLES sec-
       tion.

       Do not swap to a file on a ZFS file system. A ZFS swap file  configura-
       tion is not supported.

       Using a ZFS volume as a dump device is not supported.

SUBCOMMANDS
       All  subcommands  that modify state are logged persistently to the pool
       in their original form.

       zfs ?

	   Displays a help message.

       zfs create [[-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.

	   -o property=value	Sets the specified property  as  if  "zfs  set
				property=value"  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.

       zfs create [-s] [-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  Kbytes  to
	   ensure  that the volume has an integral number of blocks regardless
	   of blocksize.

	   -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  "zfs  set
				property=value"  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 [-rRf] filesystem|volume|snapshot

	   Destroys  the  given  dataset. By default, the command unshares any
	   file systems that are currently shared, unmounts any  file  systems
	   that  are  currently mounted, and refuses to destroy a dataset that
	   has active dependents (children, snapshots, clones).

	   -r	 Recursively destroy all children. If a snapshot is specified,
		 destroy  all snapshots with this name in descendant file sys-
		 tems.

	   -R	 Recursively destroy all  dependents,  including  cloned  file
		 systems outside the target hierarchy. If a snapshot is speci-
		 fied, destroy all snapshots with this name in descendant file
		 systems.

	   -f	 Force	an  unmount of any file systems using the "unmount -f"
		 command. 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 clone 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.

       zfs promote 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	snaphot  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 snap-
	   shot  names	of  its  own.  The  "rename" subcommand can be used to
	   rename any conflicting snapshots.

       zfs rename filesystem|volume|snapshot filesystem|volume|snapshot

	   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.

       zfs snapshot [-r] filesystem@name|volume@name

	   Creates a snapshot with the given name. See the "Snapshots" section
	   for details.

	   -r	 Recursively  create  snapshots  of  all  descendant datasets.
		 Snapshots are taken atomically, so that all  recursive  snap-
		 shots correspond to the same moment in time.

       zfs rollback [-rRf] snapshot

	   Roll  back the given dataset to a previous snapshot. When a dataset
	   is rolled back, all data that has changed  since  the  snapshot  is
	   discarded,  and the dataset reverts to the state at the time of the
	   snapshot. By default, the command refuses to roll back to  a  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 file system is unmounted and remounted, if necessary.

	   -r	 Recursively  destroy  any  snapshots more recent than the one
		 specified.

	   -R	 Recursively destroy any more recent snapshots, as well as any
		 clones of those snapshots.

	   -f	 Force	an  unmount of any file systems using the "unmount -f"
		 command.

       zfs list [-rH] [-o prop[,prop] ]... [ -t type[,type]...] [ -s prop [-s
       prop]... [ -S prop [-S prop]... [filesystem|volume|snapshot|/path-
       name|./pathname ...

	   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  datasets
	   are displayed and contain the following fields:

	     name,used,available,referenced,mountpoint

	   -H	      Used  for scripting mode. Do not print headers and sepa-
		      rate fields by a single tab instead of arbitrary	white-
		      space.

	   -r	      Recursively  display  any children of the dataset on the
		      command line.

	   -o prop    A comma-separated list of  properties  to  display.  The
		      property	must be one of the properties described in the
		      "Native Properties" section, or the special value "name"
		      to display the dataset name.

	   -s prop    A  property  to  use 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 properties 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 ordering.

			  o	 If  no  sorting  options  are	specified  the
				 existing behavior of "zfs list" is preserved.

	   -S prop    Same as the -s option, but sorts by property in descend-
		      ing order.

	   -t type    A comma-separated list of types to display, where "type"
		      is one of  "filesystem",	"snapshot"  or	"volume".  For
		      example,	specifying  "-t  snapshot" displays only snap-
		      shots.

       zfs set property=value filesystem|volume ...

	   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,  Kbytes, Mbytes, gigabytes, terabytes, petabytes,
	   exabytes, or zettabytes, respectively). Properties cannot be set on
	   snapshots.

       zfs get [-rHp] [-o field[,field]...] [-s source[,source]...] all |
       property[,property]... filesystem|volume|snapshot ...

	   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 are displayed by default, though this can be controlled
	   by using the -o option. This command 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  for
	   the given dataset.

	   -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.

	   -o field	A  comma-separated  list  of   columns	 to   display.
			"name,property,value,source" is the default value.

	   -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,none".
			The default value is all sources.

	   -p		Display numbers in parsable (exact) values.

       zfs inherit [-r] property filesystem|volume ...

	   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 inherit the given property for all children.

       zfs mount

	   Displays all ZFS file systems currently mounted.

       zfs mount[-o opts] [-O] -a

	   Mounts all available ZFS file  systems.  Invoked  automatically  as
	   part of the boot process.

	   -o opts    An optional comma-separated list of mount options to use
		      temporarily for the duration of the mount. See the "Tem-
		      porary Mount Point Properties" section for details.

	   -O	      Perform  an overlay mount. See mount(1M) for more infor-
		      mation.

       zfs mount [-o opts] [-O] filesystem

	   Mounts a specific ZFS file system. This is typically not necessary,
	   as  file systems are automatically mounted when they are created or
	   the mountpoint property has changed. See the "Mount Points" section
	   for details.

	   -o opts    An optional comma-separated list of mount options to use
		      temporarily for the duration of the mount. See the "Tem-
		      porary Mount Point Properties" section for details.

	   -O	      Perform  an overlay mount. See mount(1M) for more infor-
		      mation.

       zfs unmount -a

	   Unmounts all currently mounted ZFS file systems. Invoked  automati-
	   cally as part of the shutdown process.

       zfs unmount [-f] filesystem|mountpoint

	   Unmounts  the  given  file  system. The command can also be given a
	   path to a ZFS file system mount point on the system.

	   -f	 Forcefully unmount the file system, even if it  is  currently
		 in use.

       zfs share -a

	   Shares  all	available  ZFS file systems. This is invoked automati-
	   cally as part of the boot process.

       zfs share filesystem

	   Shares a specific ZFS file system according to the "sharenfs" prop-
	   erty.  File systems are shared when the "sharenfs" property is set.

       zfs unshare -a

	   Unshares all currently shared ZFS file  systems.  This  is  invoked
	   automatically as part of the shutdown process.

       zfs unshare [-F] filesystem|mountpoint

	   Unshares  the  given  file  system. The command can also be given a
	   path to a ZFS file system shared on the system.

	   -F	 Forcefully unshare the file system, even if it  is  currently
		 in use.

       zfs send [-i snapshot1] snapshot2

	   Creates  a  stream representation of snapshot2, 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.

	   -i snapshot1    Generate an incremental stream  from  snapshot1  to
			   snapshot2.  The incremental source snapshot1 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 snap-
			   shot2.

       The  format  of	the  stream is evolving. No backwards compatibility is
       guaranteed. You may not be able to receive your streams on future  ver-
       sions of ZFS.

       zfs receive [-vnF] filesystem|volume|snapshot
       zfs receive [-vnF] -d filesystem

	   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. The destination file system and
	   all of its child file systems are unmounted and cannot be  accessed
	   during the receive operation.

	   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 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  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,  any
	   required file systems within the specified one are created.

	   -d	 Use  the  name  of the sent snapshot to determine the name of
		 the new snapshot as described in the paragraph above.

	   -v	 Print verbose information  about  the	stream	and  the  time
		 required to perform the receive operation.

	   -n	 Do  not  actually  receive  the stream. This can be useful in
		 conjunction with the -v option to  determine  what  name  the
		 receive operation would use.

	   -F	 Force	a  rollback of the filesystem to the most recent snap-
		 shot before performing the receive operation.

       zfs jail jailid filesystem

	   Attaches the given file system to the given jail. From now on  this
	   file  system tree can be managed from within a jail if the "jailed"
	   property has been set.  To use  this  functionality,  sysctl  secu-
	   rity.jail.enforce_statfs  should  be  set  to  0  and  sysctl secu-
	   rity.jail.mount_allowed should be set to 1.

       zfs unjail jailid filesystem

	   Detaches the given file system from the given jail.

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  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 snap-
       shot 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 Taking and destroying multiple snapshots

       The   following	 command   creates   snapshots	named  "yesterday"  of
       "pool/home" and all of its descendant 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 Turning Off Compression

       The following commands turn compression off for all file systems  under
       "pool/home", but explicitly turns it on 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.

	 # zfs list

	   NAME 		     USED  AVAIL  REFER  MOUNTPOINT
	   pool 		     100G   60G       -  /pool
	   pool/home		     100G   60G       -  /export/home
	   pool/home/bob	      40G   60G     40G  /export/home/bob
	   pool/home/bob@yesterday     3M     -     40G  -
	   pool/home/anne	      60G   60G     40G  /export/home/anne

       Example 6 Setting a Quota on a ZFS File System

       The following command sets a quota of 50 gbytes for "pool/home/bob".

	 # zfs set quota=50G 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  type		 filesystem		-
	   pool/home/bob  creation	 Fri Feb 23 14:20 2007	-
	   pool/home/bob  used		 24.5K			-
	   pool/home/bob  available	 50.0G			-
	   pool/home/bob  referenced	 24.5K			-
	   pool/home/bob  compressratio  1.00x			-
	   pool/home/bob  mounted	 yes			-
	   pool/home/bob  quota 	 50G			local
	   pool/home/bob  reservation	 none			default
	   pool/home/bob  recordsize	 128K			default
	   pool/home/bob  mountpoint	 /pool/home/bob 	default
	   pool/home/bob  sharenfs	 off			default
	   pool/home/bob  shareiscsi	 off			default
	   pool/home/bob  checksum	 on			default
	   pool/home/bob  compression	 off			default
	   pool/home/bob  atime 	 on			default
	   pool/home/bob  devices	 on			default
	   pool/home/bob  exec		 on			default
	   pool/home/bob  setuid	 on			default
	   pool/home/bob  readonly	 off			default
	   pool/home/bob  zoned 	 off			default
	   pool/home/bob  snapdir	 hidden 		default
	   pool/home/bob  aclmode	 groupmask		default
	   pool/home/bob  aclinherit	 secure 		default
	   pool/home/bob  canmount	 on			default
	   pool/home/bob  xattr 	 on			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 	    compression   on
	   pool/home	    checksum	  off

       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

       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 sys-
       tem "poolB/received".  If  "poolB/received/fsA" does not exist, it will
       be created as an empty file system.

	 # zfs send poolA/fsA/fsB@snap | \
	   ssh host zfs receive -d poolB/received

       Example 14 Creating a ZFS volume as a Swap Device

       The following example shows how to create a 5-Gbyte ZFS volume and then
       add the volume as a swap device.

	 # zfs create  -V 5gb tank/vol
	 # swap -a /dev/zvol/dsk/tank/vol

       Example 15 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 16 Creating a ZFS Volume as a iSCSI Target Device

       The following example shows how to create a ZFS volume as an iSCSI tar-
       get.

	 # zfs create -V 2g pool/volumes/vol1
	 # zfs set shareiscsi=on pool/volumes/vol1
	 # iscsitadm list target
	 Target: pool/volumes/vol1
	 iSCSI Name:
	 iqn.1986-03.com.sun:02:7b4b02a6-3277-eb1b-e686-a24762c52a8c
	 Connections: 0

       After the iSCSI target is created, set up the iSCSI initiator. For more
       information about the Solaris iSCSI initiator, see the Solaris Adminis-
       tration Guide: Devices and File Systems.

EXIT STATUS
       The following exit values are returned:

       0    Successful completion.

       1    An error occurred.

       2    Invalid command line options were specified.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWzfsu			   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       gzip(1),  ssh(1),  mount(1M),  share(1M),   unshare(1M),   zonecfg(1M),
       zpool(1M), chmod(2), stat(2), fsync(3c), dfstab(4), attributes(5)

SunOS 5.11			  16 Mar 2007			       zfs(1M)


[править] Материалы по ZFS на Xgu.ru

Источник — «http://xgu.ru:81/wiki/Man:zfs»