zfs

NAME

SYNOPSIS

DESCRIPTION

Properties

Encryption

SUBCOMMANDS

zfs -?

Displays a help message.

zfs -V, --version

 

zfs version

Displays the software version of the zfs userland utility and the zfs kernel module.

Dataset Management

zfs-list(8)

Lists the property information for the given datasets in tabular form.

zfs-create(8)

Creates a new ZFS file system or volume.

zfs-destroy(8)

Destroys the given dataset(s), snapshot(s), or bookmark.

zfs-rename(8)

Renames the given dataset (filesystem or snapshot).

zfs-upgrade(8)

Manage upgrading the on-disk version of filesystems.

Snapshots

zfs-snapshot(8)

Creates snapshots with the given names.

zfs-rollback(8)

Roll back the given dataset to a previous snapshot.

zfs-hold(8)/zfs-release(8)

Add or remove a hold reference to the specified snapshot or snapshots. If a hold exists on a snapshot, attempts to destroy that snapshot by using the zfs destroy command return EBUSY.

zfs-diff(8)

Display the difference between a snapshot of a given filesystem and another snapshot of that filesystem from a later time or the current contents of the filesystem.

Clones

zfs-clone(8)

Creates a clone of the given snapshot.

zfs-promote(8)

Promotes a clone file system to no longer be dependent on its “origin” snapshot.

Send & Receive

zfs-send(8)

Generate a send stream, which may be of a filesystem, and may be incremental from a bookmark.

zfs-receive(8)

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(8) subcommand, which by default creates a full stream.

zfs-bookmark(8)

Creates a new bookmark of the given snapshot or bookmark. Bookmarks mark the point in time when the snapshot was created, and can be used as the incremental source for a zfs send command.

zfs-redact(8)

Generate a new redaction bookmark. This feature can be used to allow clones of a filesystem to be made available on a remote system, in the case where their parent need not (or needs to not) be usable.

Properties

zfs-get(8)

Displays properties for the given datasets.

zfs-set(8)

Sets the property or list of properties to the given value(s) for each dataset.

zfs-inherit(8)

Clears the specified property, causing it to be inherited from an ancestor, restored to default if no ancestor has the property set, or with the -S option reverted to the received value if one exists.

Quotas

zfs-userspace(8)/zfs-groupspace(8)/zfs-projectspace(8)

Displays space consumed by, and quotas on, each user, group, or project in the specified filesystem or snapshot.

zfs-project(8)

List, set, or clear project ID and/or inherit flag on the file(s) or directories.

Mountpoints

zfs-mount(8)

Displays all ZFS file systems currently mounted, or mount ZFS filesystem on a path described by its mountpoint property.

zfs-unmount(8)

Unmounts currently mounted ZFS file systems.

Shares

zfs-share(8)

Shares available ZFS file systems.

zfs-unshare(8)

Unshares currently shared ZFS file systems.

Delegated Administration

zfs-allow(8)

Delegate permissions on the specified filesystem or volume.

zfs-unallow(8)

Remove delegated permissions on the specified filesystem or volume.

Encryption

zfs-change-key(8)

Add or change an encryption key on the specified dataset.

zfs-load-key(8)

Load the key for the specified encrypted dataset, enabling access.

zfs-unload-key(8)

Unload a key for the specified dataset, removing the ability to access the dataset.

Channel Programs

zfs-program(8)

Execute ZFS administrative operations programmatically via a Lua script-language channel program.

Jails

zfs-jail(8)

Attaches a filesystem to a jail.

zfs-unjail(8)

Detaches a filesystem from a jail.

Waiting

zfs-wait(8)

Wait for background activity in a filesystem to complete.

EXIT STATUS

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 compression 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 listsnaps=on. The default is off. See zpoolprops(7) for more information on pool properties.

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:

The following command gets a single property value:

The following command lists all properties with local settings for pool/home/bob:

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 contents 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:

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.

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.

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:

Example 16: Setting sharenfs Property Options on a ZFS File System

The following commands show how to set sharenfs property options to enable read-write access for a set of IP addresses and to enable root access for system “neo” on the tank/home file system:

# zfs set sharenfs='rw[email protected]/16,root=neo' tank/home

If you are using DNS for host name resolution, specify the fully-qualified hostname.

Example 17: Delegating ZFS Administration Permissions on a ZFS Dataset

The following example shows how to set permissions so that user cindys can create, destroy, mount, and take snapshots on tank/cindys. The permissions on tank/cindys are also displayed.

Because the tank/cindys mount point permission is set to 755 by default, user cindys will be unable to mount file systems under tank/cindys. Add an ACE similar to the following syntax to provide mount point access:

# chmod A+user:cindys:add_subdirectory:allow /tank/cindys

Example 18: Delegating Create Time Permissions on a ZFS Dataset

The following example shows how to grant anyone in the group staff to create file systems in tank/users. This syntax also allows staff members to destroy their own file systems, but not destroy anyone else's file system. The permissions on tank/users are also displayed.

Example 19: Defining and Granting a Permission Set on a ZFS Dataset

The following example shows how to define and grant a permission set on the tank/users file system. The permissions on tank/users are also displayed.

Example 20: Delegating Property Permissions on a ZFS Dataset

The following example shows to grant the ability to set quotas and reservations on the users/home file system. The permissions on users/home are also displayed.

Example 21: Removing ZFS Delegated Permissions on a ZFS Dataset

The following example shows how to remove the snapshot permission from the staff group on the tank/users file system. The permissions on tank/users are also displayed.

Example 22: Showing the differences between a snapshot and a ZFS Dataset

The following example shows how to see what has changed between a prior snapshot of a ZFS dataset and its current state. The -F option is used to indicate type information for the files affected.

Example 23: Creating a bookmark

The following example create a bookmark to a snapshot. This bookmark can then be used instead of snapshot in send streams.

# zfs bookmark rpool@snapshot rpool#bookmark

Example 24: Setting sharesmb Property Options on a ZFS File System

The following example show how to share SMB filesystem through ZFS. Note that a user and their password must be given.

# smbmount //127.0.0.1/share_tmp /mnt/tmp -o user=workgroup/turbo,password=obrut,uid=1000

Minimal /etc/samba/smb.conf configuration is required, as follows.

Samba will need to bind to the loopback interface for the ZFS utilities to communicate with Samba. This is the default behavior for most Linux distributions.

Samba must be able to authenticate a user. This can be done in a number of ways (passwd(5), LDAP, smbpasswd(5), &c.). How to do this is outside the scope of this document – refer to smb.conf(5) for more information.

See the USERSHARES section for all configuration options, in case you need to modify any options of the share afterwards. Do note that any changes done with the net(8) command will be undone if the share is ever unshared (like via a reboot).

ENVIRONMENT VARIABLES

ZFS_COLOR

Use ANSI color in zfs diff and zfs list output.

ZFS_MOUNT_HELPER

Cause zfs mount to use mount(8) to mount ZFS datasets. This option is provided for backwards compatibility with older ZFS versions.

ZFS_SET_PIPE_MAX

Tells zfs to set the maximum pipe size for sends/recieves. Disabled by default on Linux due to an unfixed deadlock in Linux's pipe size handling code.

INTERFACE STABILITY

SEE ALSO