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When I change a file in an AUFS-mount, that change gets stored somehow in the rw-layer.

It is clear how new/changed files are stored in the rw-layer, but how get deleted files remembered there?

Udo G
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1 Answers1

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All union filesystems with read-only and read-write branches use some form of "whiteout" marker on a read-write branch to suppress a file that exists on a read-only branch. AUFS is no different.

For AUFS, the whiteout markers are files called:

.wh.<filename>

located in the same directory where the deleted file used to live, and where <filename> is the filename of the file that was deleted.

Ref: aufs manpage, information about whiteout

Celada
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