[rdiff-backup-users] initial rdiff-backup for large repository over Internet (and connection lost)

[Nicolas]

Hi all,

I'm an happy rdiff-backup user for many years.

Years ago I setup a rdiff-backup from a WWW server to a local server.
Internet connection is limited to 2Mbps between the 2 servers.
As /var/www was initially empty, rdiff-backup as done its backup job 
everyday without problem, with many sites added in /var/www.

Now /var/www is 14G large and I need to fresh start the backup 
(destination directory has been deleted).

Bad thing is that trying to first sync source and destination via the 
command :
nice -n 19 rdiff-backup --force $SOURCE $DEST::$DESTDIR
always ends with network (Internet error) like these :
Found interrupted initial backup. Removing...
Write failed: Broken pipe
Fatal Error: Lost connection to the remote system

What would be proper way to first sync rdiff-backup ?
Would a previous rsync help, so that only meta-datas would be written by 
rdiff ?

Thanks in advance for your thought.
Nicolas