BTRFS-SEND(8)			     BTRFS			 BTRFS-SEND(8)

NAME
       btrfs-send - generate a stream of changes between two subvolume
       snapshots

SYNOPSIS
       btrfs send [-ve] [-p <parent>] [-c <clone-src>] [-f <outfile>] <subvol>
       [<subvol>...]

DESCRIPTION
       This command will generate a stream of instructions that describe
       changes between two subvolume snapshots. The stream can be consumed by
       the btrfs receive command to replicate the sent snapshot on a different
       filesystem.  The command operates in two modes: full and incremental.

       All snapshots involved in one send command must be read-only, and this
       status cannot be changed as long as there's a running send operation
       that uses the snapshot. Read-only mount of the subvolume is not
       sufficient, there's no way to guarantee that there won't be any other
       writable mount of the same subvolume that would potentially write while
       send would be running.

       In the full mode, the entire snapshot data and metadata will end up in
       the stream.

       In the incremental mode (options -p and -c), previously sent snapshots
       that are available on both the sending and receiving side can be used
       to reduce the amount of information that has to be sent to reconstruct
       the sent snapshot on a different filesystem.

       The -p <parent> option can be omitted when -c <clone-src> options are
       given, in which case btrfs send will determine a suitable parent from
       among the clone sources.

       You must not specify clone sources unless you guarantee that these
       snapshots are exactly in the same state on both sides--both for the
       sender and the receiver. For implications of changed read-write status
       of a received snapshot please see section SUBVOLUME FLAGS in
       btrfs-subvolume(8).

       Options

       -e     if sending multiple subvolumes at once, use the new format and
	      omit the end cmd marker in the stream separating the subvolumes

       -p <parent>
	      send an incremental stream from parent to subvol

       -c <clone-src>
	      use this snapshot as a clone source for an incremental send
	      (multiple allowed)

       -f <outfile>
	      output is normally written to standard output so it can be, for
	      example, piped to btrfs receive. Use this option to write it to
	      a file instead.

       --no-data
	      send in NO_FILE_DATA mode

	      The output stream does not contain any file data and thus cannot
	      be used to transfer changes. This mode is faster and is useful
	      to show the differences in metadata.

       --proto <N>
	      use send protocol version N

	      The default is 1, which was the original protocol version.
	      Version 2 encodes file data slightly more efficiently; it is
	      also required for sending compressed data directly (see
	      --compressed-data). Version 2 requires at least btrfs-progs 6.0
	      on both the sender and receiver and at least Linux 6.0 on the
	      sender. Passing 0 means to use the highest version supported by
	      the running kernel.

       --compressed-data
	      send data that is compressed on the filesystem directly without
	      decompressing it

	      If the receiver supports the BTRFS_IOC_ENCODED_WRITE ioctl
	      (added in Linux 6.0), it can also write it directly without
	      decompressing it.	 Otherwise, the receiver will fall back to
	      decompressing it and writing it normally.

	      This requires protocol version 2 or higher. If --proto was not
	      used, then --compressed-data implies --proto 2.

       -q|--quiet
	      (deprecated) alias for global -q option

       -v|--verbose
	      (deprecated) alias for global -v option

       Global options

       -q|--quiet
	      suppress all messages except errors

       -v|--verbose
	      increase output verbosity, print generated commands in a
	      readable form

EXIT STATUS
       btrfs send returns a zero exit status if it succeeds. Non zero is
       returned in case of failure.

AVAILABILITY
       btrfs is part of btrfs-progs.  Please refer to the documentation at
       https://btrfs.readthedocs.io.

SEE ALSO
       btrfs-receive(8), btrfs-subvolume(8), mkfs.btrfs(8)

6.16.1			      September 10, 2025		 BTRFS-SEND(8)