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@@ -480,6 +480,52 @@ If you can reproduce the issue with the proven filesystem, please file an
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issue in the |project_name| issue tracker about that.
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+Why does running 'borg check --repair' warn about data loss?
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+------------------------------------------------------------
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+
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+Repair usually works for recovering data in a corrupted archive. However,
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+it's impossible to predict all modes of corruption. In some very rare
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+instances, such as malfunctioning storage hardware, additional repo
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+corruption may occur. If you can't afford to lose the repo, it's strongly
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+recommended that you perform repair on a copy of the repo.
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+
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+In other words, the warning is there to emphasize that |project_name|:
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+ - Will perform automated routines that modify your backup repository
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+ - Might not actually fix the problem you are experiencing
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+ - Might, in very rare cases, further corrupt your repository
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+
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+In the case of malfunctioning hardware, such as a drive or USB hub
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+corrupting data when read or written, it's best to diagnose and fix the
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+cause of the initial corruption before attempting to repair the repo. If
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+the corruption is caused by a one time event such as a power outage,
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+running `borg check --repair` will fix most problems.
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+
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+
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+Why isn't there more progress / ETA information displayed?
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+----------------------------------------------------------
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+
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+Some borg runs take quite a bit, so it would be nice to see a progress display,
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+maybe even including a ETA (expected time of "arrival" [here rather "completion"]).
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+
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+For some functionality, this can be done: if the total amount of work is more or
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+less known, we can display progress. So check if there is a ``--progress`` option.
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+
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+But sometimes, the total amount is unknown (e.g. for ``borg create`` we just do
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+a single pass over the filesystem, so we do not know the total file count or data
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+volume before reaching the end). Adding another pass just to determine that would
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+take additional time and could be incorrect, if the filesystem is changing.
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+
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+Even if the fs does not change and we knew count and size of all files, we still
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+could not compute the ``borg create`` ETA as we do not know the amount of changed
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+chunks, how the bandwidth of source and destination or system performance might
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+fluctuate.
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+
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+You see, trying to display ETA would be futile. The borg developers prefer to
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+rather not implement progress / ETA display than doing futile attempts.
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+
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+See also: https://xkcd.com/612/
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+
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+
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Requirements for the borg single-file binary, esp. (g)libc?
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-----------------------------------------------------------
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Thomas Waldmann