Provided by: zfsutils-linux_2.1.5-1ubuntu6~22.04.5_amd64 
NAME
zfs-receive — create snapshot from backup stream
SYNOPSIS
zfs receive [-FhMnsuv] [-o origin=snapshot] [-o property=value] [-x property] filesystem|volume|snapshot
zfs receive [-FhMnsuv] [-d|-e] [-o origin=snapshot] [-o property=value] [-x property] filesystem
zfs receive -A filesystem|volume
DESCRIPTION
zfs receive [-FhMnsuv] [-o origin=snapshot] [-o property=value] [-x property] filesystem|volume|snapshot
zfs receive [-FhMnsuv] [-d|-e] [-o origin=snapshot] [-o property=value] [-x property] 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. For zvols, the destination device link is
destroyed and recreated, which means the zvol 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.
The ability to send and receive deduplicated send streams has been removed. However, a deduplicated
send stream created with older software can be converted to a regular (non-deduplicated) stream by
using the zstream redup command.
If -o property=value or -x property is specified, it applies to the effective value of the property
throughout the entire subtree of replicated datasets. Effective property values will be set (-o) or
inherited (-x) on the topmost in the replicated subtree. In descendant datasets, if the property is
set by the send stream, it will be overridden by forcing the property to be inherited from the top‐most
file system. Received properties are retained in spite of being overridden and may be restored with
zfs inherit -S. Specifying -o origin=snapshot is a special case because, even if origin is a read-only
property and cannot be set, it's allowed to receive the send stream as a clone of the given snapshot.
Raw encrypted send streams (created with zfs send -w) may only be received as is, and cannot be re-
encrypted, decrypted, or recompressed by the receive process. Unencrypted streams can be received as
encrypted datasets, either through inheritance or by specifying encryption parameters with the -o
options. Note that the keylocation property cannot be overridden to prompt during a receive. This is
because the receive process itself is already using the standard input for the send stream. Instead,
the property can be overridden after the receive completes.
The added security provided by raw sends adds some restrictions to the send and receive process. ZFS
will not allow a mix of raw receives and non-raw receives. Specifically, any raw incremental receives
that are attempted after a non-raw receive will fail. Non-raw receives do not have this restriction
and, therefore, are always possible. Because of this, it is best practice to always use either raw
sends for their security benefits or non-raw sends for their flexibility when working with encrypted
datasets, but not a combination.
The reason for this restriction stems from the inherent restrictions of the AEAD ciphers that ZFS uses
to encrypt data. When using ZFS native encryption, each block of data is encrypted against a randomly
generated number known as the "initialization vector" (IV), which is stored in the filesystem metadata.
This number is required by the encryption algorithms whenever the data is to be decrypted. Together,
all of the IVs provided for all of the blocks in a given snapshot are collectively called an "IV set".
When ZFS performs a raw send, the IV set is transferred from the source to the destination in the send
stream. When ZFS performs a non-raw send, the data is decrypted by the source system and re-encrypted
by the destination system, creating a snapshot with effectively the same data, but a different IV set.
In order for decryption to work after a raw send, ZFS must ensure that the IV set used on both the
source and destination side match. When an incremental raw receive is performed on top of an existing
snapshot, ZFS will check to confirm that the "from" snapshot on both the source and destination were
using the same IV set, ensuring the new IV set is consistent.
The name of the snapshot (and file system, if a full stream is received) that this subcommand creates
depends on the argument type and the use of the -d or -e options.
If the argument is a snapshot name, the specified snapshot is created. If the argument is a file
system or volume name, a snapshot with the same name as the sent snapshot is created within the
specified filesystem or volume. If neither of the -d or -e options are specified, the provided target
snapshot name is used exactly as provided.
The -d and -e options cause the file system name of the target snapshot to be determined by appending a
portion of the sent snapshot's name to the specified target filesystem. If the -d option is specified,
all but the first element of the sent snapshot's file system path (usually the pool name) is used and
any required intermediate file systems within the specified one are created. If the -e option is
specified, then only the last element of the sent snapshot's file system name (i.e. the name of the
source file system itself) is used as the target file system name.
-F Force a rollback of the file system to the most recent snapshot before performing the receive
operation. If receiving an incremental replication stream (for example, one generated by zfs send
-R [-i|-I]), destroy snapshots and file systems that do not exist on the sending side.
-d Discard the first element of the sent snapshot's file system name, using the remaining elements to
determine the name of the target file system for the new snapshot as described in the paragraph
above.
-e Discard all but the last element of the sent snapshot's file system name, using that element to
determine the name of the target file system for the new snapshot as described in the paragraph
above.
-h Skip the receive of holds. There is no effect if holds are not sent.
-M Force an unmount of the file system while receiving a snapshot. This option is not supported on
Linux.
-n Do not actually receive the stream. This can be useful in conjunction with the -v option to verify
the name the receive operation would use.
-o origin=snapshot
Forces the stream to be received as a clone of the given snapshot. If the stream is a full send
stream, this will create the filesystem described by the stream as a clone of the specified
snapshot. Which snapshot was specified will not affect the success or failure of the receive, as
long as the snapshot does exist. If the stream is an incremental send stream, all the normal
verification will be performed.
-o property=value
Sets the specified property as if the command zfs set property=value was invoked immediately before
the receive. When receiving a stream from zfs send -R, causes the property to be inherited by all
descendant datasets, as through zfs inherit property was run on any descendant datasets that have
this property set on the sending system.
If the send stream was sent with -c then overriding the compression property will have no affect on
received data but the compression property will be set. To have the data recompressed on receive
remove the -c flag from the send stream.
Any editable property can be set at receive time. Set-once properties bound to the received data,
such as normalization and casesensitivity, cannot be set at receive time even when the datasets are
newly created by zfs receive. Additionally both settable properties version and volsize cannot be
set at receive time.
The -o option may be specified multiple times, for different properties. An error results if the
same property is specified in multiple -o or -x options.
The -o option may also be used to override encryption properties upon initial receive. This allows
unencrypted streams to be received as encrypted datasets. To cause the received dataset (or root
dataset of a recursive stream) to be received as an encryption root, specify encryption properties
in the same manner as is required for zfs create. For instance:
# zfs send tank/test@snap1 | zfs recv -o encryption=on -o keyformat=passphrase -o
keylocation=file:///path/to/keyfile
Note that -o keylocation=prompt may not be specified here, since the standard input is already
being utilized for the send stream. Once the receive has completed, you can use zfs set to change
this setting after the fact. Similarly, you can receive a dataset as an encrypted child by
specifying -x encryption to force the property to be inherited. Overriding encryption properties
(except for keylocation) is not possible with raw send streams.
-s If the receive is interrupted, save the partially received state, rather than deleting it.
Interruption may be due to premature termination of the stream (e.g. due to network failure or
failure of the remote system if the stream is being read over a network connection), a checksum
error in the stream, termination of the zfs receive process, or unclean shutdown of the system.
The receive can be resumed with a stream generated by zfs send -t token, where the token is the
value of the receive_resume_token property of the filesystem or volume which is received into.
To use this flag, the storage pool must have the extensible_dataset feature enabled. See
zpool-features(7) for details on ZFS feature flags.
-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 will be set or inherited,
depending on whether the property is inheritable or not.
In the case of an incremental update, -x leaves any existing local setting or explicit inheritance
unchanged.
All -o restrictions (e.g. set-once) apply equally to -x.
zfs receive -A filesystem|volume
Abort an interrupted zfs receive -s, deleting its saved partially received state.
SEE ALSO
zfs-send(8), zstream(8)
OpenZFS February 16, 2020 ZFS-RECEIVE(8)