Hard link limitations in union filesystems #1211
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sudo-bmitch
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layer.md
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| @@ -69,6 +69,8 @@ Where supported, MUST include file attributes for Additions and Modifications in | |||
| - Non-directory files are considered "hardlinked" when their link count is greater than 1. | |||
| - Hardlinked files are on a same device (i.e. comparing Major:Minor pair) and have the same inode. | |||
| - The corresponding files that share the link with the > 1 linkcount may be outside the directory that the changeset is being produced from, in which case the `linkname` is not recorded in the changeset. | |||
| - Union filesystem implementations may have limited or no support for hardlinks, particularly when a change is made to a hardlinked file or a hardlink is created to a file in a lower filesystem. | |||
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Do you want to include this link? - https://docs.kernel.org/filesystems/overlayfs.html#index
Might be worth if or when someone revisits this section.
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Okay, I've included that.
Signed-off-by: Brandon Mitchell <[email protected]>
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Fixes #1204.
This calls out the limitations of hard links in a union filesystem. E.g. in some configurations a hard link may be broken when multiple files are hard linked and a change is made to one file or a hard link is created to a lower filesystem file. See https://docs.kernel.org/filesystems/overlayfs.html#index