1nbdkit-ext2-filter(1) NBDKIT nbdkit-ext2-filter(1)
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6 nbdkit-ext2-filter - read and write files inside ext2, ext3 or ext4
7 filesystems
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10 nbdkit --filter=ext2 file fs.img ext2file=/disks/disk.raw
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12 nbdkit --filter=ext2 --filter=partition file fs.img \
13 partition=1 ext2file=exportname
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16 "nbdkit-ext2-filter" is an nbdkit filter which can read and write files
17 inside ext2, ext3 or ext4 filesystem images.
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19 Suppose you have an ext2/3/4 filesystem image called fs.img which
20 contains inside itself a file called disk.raw inside a directory on the
21 filesystem called /disks, then you could serve that file over NBD
22 using:
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24 nbdkit --filter=ext2 file fs.img ext2file=/disks/disk.raw
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26 Commonly disk images are partitioned. In that case, you must select
27 just the partition of a disk image that contains an ext2 filesystem, by
28 using nbdkit-partition-filter(1):
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30 nbdkit --filter=ext2 --filter=partition file fs.img \
31 partition=1 ext2file=/disks/disk.raw
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33 This filter can both read and write to the file inside the filesystem.
34 Use the -r flag to force a readonly connection, but note this does not
35 guarantee that no writes are made to the filesystem. In particular we
36 may have to replay the ext3 journal in order to open a filesystem even
37 read-only.
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39 The filter does not support multiple parallel connections, because
40 there is a risk of corrupting the filesystem (as if the filesystem was
41 mounted by multiple machines). If a second connection is made to
42 nbdkit, it will block until the first connection closes.
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44 The filter is implemented using the ext2fs library which is provided in
45 most Linux distros, and also available as part of the e2fsprogs
46 project.
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48 nbdkit-guestfs-plugin(1) is a more generic plugin which can read files
49 from all kinds of different filesystem types, even if they are
50 partitioned or use logical volumes. It uses libguestfs instead of
51 e2fsprogs.
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54 ext2file=PATH
55 The full path of the file within the filesystem that will be
56 exposed over NBD. The path must be absolute (starts with "/").
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58 ext2file=exportname
59 The plugin will expose the path within the filesystem chosen by the
60 exportname passed by the client. Note that this mode allows the
61 client to deduce which files exist within the disk image, which may
62 be a security risk in some situations.
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65 $filterdir/nbdkit-ext2-filter.so
66 The filter.
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68 Use "nbdkit --dump-config" to find the location of $filterdir.
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71 "nbdkit-ext2-filter" first appeared in nbdkit 1.18, replacing an older
72 "nbdkit-ext2-plugin" from nbdkit 1.4.
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75 nbdkit(1), nbdkit-plugin(3), nbdkit-partition-filter(1),
76 nbdkit-guestfs-plugin(1), http://e2fsprogs.sourceforge.net/,
77 fuse2fs(1).
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80 Eric Blake
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82 Richard W.M. Jones
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85 Copyright (C) 2018-2020 Red Hat Inc.
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88 Redistribution and use in source and binary forms, with or without
89 modification, are permitted provided that the following conditions are
90 met:
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92 · Redistributions of source code must retain the above copyright
93 notice, this list of conditions and the following disclaimer.
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95 · Redistributions in binary form must reproduce the above copyright
96 notice, this list of conditions and the following disclaimer in the
97 documentation and/or other materials provided with the
98 distribution.
99
100 · Neither the name of Red Hat nor the names of its contributors may
101 be used to endorse or promote products derived from this software
102 without specific prior written permission.
103
104 THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND ANY
105 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
106 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
107 PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR CONTRIBUTORS BE
108 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
109 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
110 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
111 BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
112 WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
113 OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
114 ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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118nbdkit-1.18.4 2020-04-16 nbdkit-ext2-filter(1)