1BTRFS-SEND(8) Btrfs Manual BTRFS-SEND(8)
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6 btrfs-send - generate a stream of changes between two subvolume
7 snapshots
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10 btrfs send [-ve] [-p <parent>] [-c <clone-src>] [-f <outfile>] <subvol>
11 [<subvol>...]
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14 This command will generate a stream of instructions that describe
15 changes between two subvolume snapshots. The stream can be consumed by
16 the btrfs receive command to replicate the sent snapshot on a different
17 filesystem. The command operates in two modes: full and incremental.
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19 All snapshots involved in one send command must be read-only, and this
20 status cannot be changed as long as there’s a running send operation
21 that uses the snapshot.
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23 In the full mode, the entire snapshot data and metadata will end up in
24 the stream.
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26 In the incremental mode (options -p and -c), previously sent snapshots
27 that are available on both the sending and receiving side can be used
28 to reduce the amount of information that has to be sent to reconstruct
29 the sent snapshot on a different filesystem.
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31 The -p <parent> option can be omitted when -c <clone-src> options are
32 given, in which case btrfs send will determine a suitable parent from
33 among the clone sources.
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35 You must not specify clone sources unless you guarantee that these
36 snapshots are exactly in the same state on both sides—both for the
37 sender and the receiver.
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39 Options
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41 -e
42 if sending multiple subvolumes at once, use the new format and omit
43 the end cmd marker in the stream separating the subvolumes
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45 -p <parent>
46 send an incremental stream from parent to subvol
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48 -c <clone-src>
49 use this snapshot as a clone source for an incremental send
50 (multiple allowed)
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52 -f <outfile>
53 output is normally written to standard output so it can be, for
54 example, piped to btrfs receive. Use this option to write it to a
55 file instead.
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57 --no-data
58 send in NO_FILE_DATA mode
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60 The output stream does not contain any file data and thus cannot be
61 used to transfer changes. This mode is faster and is useful to show
62 the differences in metadata.
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64 -v|--verbose
65 enable verbose output, print generated commands in a readable form,
66 (each occurrence of this option increases the verbosity level)
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68 -q|--quiet
69 suppress all messages except errors
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72 btrfs send returns a zero exit status if it succeeds. Non zero is
73 returned in case of failure.
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76 btrfs is part of btrfs-progs. Please refer to the btrfs wiki
77 http://btrfs.wiki.kernel.org for further details.
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80 mkfs.btrfs(8), btrfs-receive(8)
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84Btrfs v5.6 04/05/2020 BTRFS-SEND(8)