BTRFS-SEND(8) Btrfs Manual BTRFS-SEND(8)
NAME
btrfs-send - generate a stream of changes between two subvolumes
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 subvolumes. The stream can be consumed by the btrfs
receive command to replicate the sent subvolume on a different
filesystem. The command operates in two modes: full and incremental.
All subvolumes involved in one send command must be read-only (ie. the
read-only snapshots and this status cannot be changed if there's a
running send operation that uses the subvolume).
In the full mode, the entire subvolume data and metadata will end up in
the stream.
In the incremental mode (options -p and -c), there can be one or more
parent subvolumes that will establish the base for determining the
changes. The final stream will be smaller compared to the full mode.
It is allowed to omit the -p <parent> option when -c <clone-src>
options are given, in which case btrfs send will determine a suitable
parent among the clone sources itself.
You must not specify clone sources unless you guarantee that these
snapshots are exactly in the same state on both sides, the sender and
the receiver.
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 outout so it can be eg.
piped to receive, use this option to write it to a file
--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 useful to show
the differences in metadata.
-v|--verbose
enable verbose output, print generated commands in a readable form,
(each occurrence of this option increases the verbosity level)
-q|--quiet
suppress all messagese except errors
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 btrfs wiki
http://btrfs.wiki.kernel.org for further details.
SEE ALSO
mkfs.btrfs(8), btrfs-receive(8)
Btrfs v4.9.1 08/06/2017 BTRFS-SEND(8)