[rdiff-backup-users] How to cope with missing 'rdiff-backup-data' in destination directory

[R. Diez]

Hi all:

I have a big set of backup files on a slow USB drive (my Linux laptop 
only has USB 2.0 ports). In order to quickly update the backup, I have 
been using rsync in "look only at modification time" mode.

Now I wish to switch to rdiff-backup. The destination directory already 
contains an exact copy of the source directory, but is missing the 
'rdiff-backup-data' directory, so I am getting error "Bad directory 
/home/rdiez/blah/blah. It doesn't appear to be an rdiff-backup 
destination dir".

I don't want to copy all files again, as it would take hours. Is there a 
way to tell rdiff-backup to regenerate the 'rdiff-backup-data' directory?

By the way, this is the little wrapper script that I am using:

https://github.com/rdiez/Tools/blob/master/BackupFiles/update-backup-mirror-by-modification-time.sh

Thanks in advance,
  rdiez