1DAXIO(1) PMDK Programmer's Manual DAXIO(1)
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6 daxio - Perform I/O on Device DAX devices or zero a Device DAX device
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9 $ daxio [<options>]
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12 The daxio utility performs I/O on Device DAX devices or zero a Device
13 DAX device. Since the standard I/O APIs (read/write) cannot be used
14 with Device DAX, data transfer is performed on a memory-mapped device.
15 The daxio may be used to dump Device DAX data to a file, restore data
16 from a backup copy, move/copy data to another device or to erase data
17 from a device.
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19 There must be at least one Device DAX device involved either as the in‐
20 put or output. If input or output is not specified, it will default to
21 stdin or stdout respectively.
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23 No length specified will default to input file/device length or to the
24 output file/device length, if input is a special char file or stdin.
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26 For a Device DAX device, daxio will attempt to clear bad blocks within
27 the range of writes before performing the I/O (it can be turned off us‐
28 ing the `–clear-bad-blocks=no' option).
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31 -i, --input Input device or file to read from.
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33 -o, --output Output device or file to write to.
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35 -z, --zero Zero the output device for len size, or the entire device if
36 no length was provided. The output device must be a Device DAX device.
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38 -b, --clear-bad-blocks=<yes|no> Clear bad blocks within the range of
39 writes before performing the I/O (default: yes).
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41 -l, --len The length in bytes to perform the I/O. To make passing in
42 size easier for kibi, mebi, gibi, and tebi bytes, len may include unit
43 suffix. The len format must be compliant with the format specified in
44 IEC 80000-13, IEEE 1541 or the Metric Interchange Format. These stan‐
45 dards accept SI units with obligatory B - kB, MB, GB, ... (multiplier
46 by 1000) suffixes, and IEC units with optional “iB” - KiB, MiB, GiB,
47 ..., K, M, G, ... (multiplier by 1024) suffixes.
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49 -s, --seek The number of bytes to skip over on the output before per‐
50 forming a write. The same suffixes are accepted as for len.
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52 -k, --skip The number of bytes to skip over on the input before per‐
53 forming a read. The same suffixes are accepted as for len.
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55 -V, --version
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57 Prints the version of daxio.
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59 -h, --help
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61 Prints synopsis and list of options.
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64 # daxio --zero /dev/dax1.0
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66 # daxio --input=/dev/dax1.0 --output=/home/myfile --len=2M --seek=4096
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68 # cat /dev/zero | daxio --output=/dev/dax1.0
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70 # daxio --input=/dev/zero --output=/dev/dax1.0 --skip=4096
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73 daxctl(1), ndctl(1) and <https://pmem.io>
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77PMDK - daxio version 1.4 2020-10-28 DAXIO(1)