Re: [rdiff-backup-users] Bug report: Symbolic link replacing directory

[Finn-Arne Johansen]

john wrote:
> Hi all!
>
> How to confuse a backup system? Maybe you should try this approach, it
> worked for me. :-(
>
> Confusion recipe for rdiff-backup V12.6:
>
> Create two directories (dir1 and dir2).
> Create two files, dir1/file1 and dir2/file2.
> Backup the stuff.
> Move file2 to dir1/file2.
> Remove dir2.
> Symlink dir2 -> dir1
> Backup the stuff.
>
> This gives the following error message:
>
> UpdateError dir1/file2 File changed from regular file before signature.
>
> And file2 is not in the backup.
>
> I cannot see any mention of this behaviour in the changelog of V12.7,
> so I gues this version should do the same. Otherwise I would have
> updated and tested again.
>
> As a workaround to this bug, I thought about deleting dir2 in the
> increment directory. That way I would lose old history, but that
> doesn`t really matter. But what to do with the metadata, so the whole
> backup remains consistent?

Wouldnt it be better to remove dir2 , and not create the symlink until 
after a backup has run.

Another approach, depending on how much data there is, is to first do a 
hardlink. something like:
 mkdir dir1 dir2
 for FILE in dir1/file1 dir2/file2 ; do
  echo $FILE > $FILE
 done
 rdiff-backup --add-your-options
 ln dir2/file2 dir1
 rdiff-backup --add-your-options
 rm -rf dir2
 rdiff-backup --add-your-options
 ln -s dir1 dir2
 rdiff-backup --add-your-options

I guess that will cause less pain to your backup, but I'm not sure.

// faj