--dry-run reliability ?

[François]

Le samedi 14 juin 2014, 20:41:14 Kevin Korb a écrit :
> The difference is pretty simple.  An ACL (or permissions or ownership)
> change does not require the transfer of a file only a change to the
> file's attributes.  Therefore it does not affect the transfer size.
> 
> When you use the cp -al then rsync method rsync doesn't pay any
> attention to previous backups therefor it just changes the ACL which
> affects all links to the same inode.
> 
> Rsync --link-dest otoh cares about previous backups.  It assumes you
> want to have the old metadata on the old backup(s) and the new
> metadata on the new backup.  Since metadata applies to the inode not
> the link the only way it can accomplish this is to duplicate the file
> instead of linking it.  Therefore, you now have 2 copies of the file
> with different ACLs.  This increases disk space usage without
> transferring any data.

Wow, that's a clear explanation :)
Thanks *a lot* !

-- 
François