Re: [rdiff-backup-users] howto resume failed backup

[Steven Willoughby]

On 12/04/2009 07:44 AM, elemental code wrote:
> Hi,
>
> I'm backuping a host through an unstable link. So, each time the ssh
> connection get broken and rdiff-backup can't finish the backup.
> When I restart it, I get "Previous backup seems to have failed,
> regressing destination now" and all restart to zero.
> Is there a way to resume a backup without regressing destination?
>
> The only solution I found for the moment is to :
> - first to use rsync to backup to a folder on the destination (I can
> resume with it)
> - rdiff in local on the destination host but it use twice the space.
>
> Have you an other idea to do it without using twice the space?

Yes, there are currently a couple of options.  First, if you tunnel 
through something like openvpn with the --ping-restart option, 
rdiff-backup won't notice temporary connection failures.

Another option is to use rsync for the transfer but use hardlinks to 
avoid using double the space.  I'm successfully doing this with large 
backups where doing an increment sometimes takes weeks to complete (due 
to a very slow link).  The steps I take (on the destination machine) are:

cp -rpl $dest $temp
rm -r $temp/rdiff-backup-data

rsync -vyaz --partial --delete-delay $host:$source/ $temp/
# repeat rsync step until successful

rdiff-backup $temp $dest
rm -r $temp

Steven