Re: [rdiff-backup-users] unable to recover from interrupted backup

[Dominic Raferd]

Ben Tucker wrote:
> I had a machine fail in the midst of backing up a couple weeks ago and
> ever since I have been unable to get it to successfully backup.
> rdiff-backup --check-destination-dir runs without error, but then
> running the actual backup command results in an exception.  I'm
> running 1.2.8 stock deb install on Ubuntu jaunty.  The client machine
> is also running 1.2.8 (also ubuntu).  These are the only versions of
> rdiff-backup with have been used.  I'd greatly appreciate any pointers
> on how to resolve this.  Thanks!
Did you get this sorted? It sounds an alarming problem for any of us who 
have important repositories of data going back over a long period; the 
whole thing could get trashed by one failed backup!

I give below a way (posted here by Steven a few weeks ago) to force a 
regression. This might undo the 'bad' backup(s) that you have and then 
allow you to make further backups. I haven't had the need to try it but 
it might help you:

Dominic
----------------
While rdiff-backup is making a backup it creates a new 
"current_mirror.$timestamp.data" file in the rdiff-backup-data 
destination directory.  Once it's done making the backup, it deletes the 
old current_mirror file.  In other words, while the backup is running 
there are two current_mirror files. In order to undo a backup, you'll 
need to to create a fake current_mirror file with the timestamp of the 
previous backup and run "rdiff-backup -v6 --check-destination-dir 
$dest".  rdiff-backup will be fooled into thinking the latest backup 
failed and revert it.

I do not know of a way to regress more than one backup at once, but this 
method should work multiple times.

P.S. A full example in case my description isn't clear:

$ mkdir source

$ echo 1 > source/a

$ echo 2 > source/b

$ rdiff-backup source dest

$ ls dest
a  b  rdiff-backup-data

$ rm source/a

$ rdiff-backup source dest

$ ls dest
b  rdiff-backup-data

$ ls dest/rdiff-backup-data/mirror*
dest/rdiff-backup-data/mirror_metadata.2009-07-03T18:47:33-06:00.diff.gz
dest/rdiff-backup-data/mirror_metadata.2009-07-03T18:48:12-06:00.snapshot.gz 


$ echo PID 999999 > \
dest/rdiff-backup-data/current_mirror.2009-07-03T18:47:33-06:00.diff.gz

$ rdiff-backup -v6 --check-destination-dir dest
Using rdiff-backup version 1.2.7
... snip ...
Regressing to Fri Jul  3 18:47:33 2009
... snip ...
Regressing file a
... snip ...
Cleaning up

$ ls dest
a  b  rdiff-backup-data