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@@ -177,49 +177,6 @@ class CheckMixIn:
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lost data. However, this "healing process" can only happen in repair mode.
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Thus it is advised to run ``--repair`` a second time after creating some new
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backups.
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-
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- Technical description
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- +++++++++++++++++++++
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-
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- First, the underlying repository data files are checked:
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-
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- - For all segments, the segment magic header is checked.
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- - For all objects stored in the segments, all metadata (e.g. CRC and size) and
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- all data is read. The read data is checked by size and CRC. Bit rot and other
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- types of accidental damage can be detected this way.
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- - In repair mode, if an integrity error is detected in a segment, try to recover
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- as many objects from the segment as possible.
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- - In repair mode, make sure that the index is consistent with the data stored in
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- the segments.
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- - If checking a remote repo via ``ssh:``, the repo check is executed on the server
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- without causing significant network traffic.
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- - The repository check can be skipped using the ``--archives-only`` option.
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- - A repository check can be time consuming. Partial checks are possible with the
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- ``--max-duration`` option.
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-
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- Second, the consistency and correctness of the archive metadata is verified:
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-
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- - Is the repo manifest present? If not, it is rebuilt from archive metadata
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- chunks (this requires reading and decrypting of all metadata and data).
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- - Check if archive metadata chunk is present; if not, remove archive from manifest.
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- - For all files (items) in the archive, for all chunks referenced by these
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- files, check if chunk is present. In repair mode, if a chunk is not present,
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- replace it with a same-size replacement chunk of zeroes. If a previously lost
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- chunk reappears (e.g. via a later backup), in repair mode the all-zero replacement
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- chunk will be replaced by the correct chunk. This requires reading of archive and
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- file metadata, but not data.
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- - In repair mode, when all the archives were checked, orphaned chunks are deleted
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- from the repo. One cause of orphaned chunks are input file related errors (like
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- read errors) in the archive creation process.
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- - In verify-data mode, a complete cryptographic verification of the archive data
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- integrity is performed. This conflicts with ``--repository-only`` as this mode
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- only makes sense if the archive checks are enabled. The full details of this mode
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- are documented above.
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- - If checking a remote repo via ``ssh:``, the archive check is executed on the
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- client machine because it requires decryption, and this is always done client-side
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- as key access is needed.
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- - The archive checks can be time consuming; they can be skipped using the
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- ``--repository-only`` option.
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"""
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)
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subparser = subparsers.add_parser(
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Daniel Rudolf