For the purpises of this page backups are being done from 'liveserver' to 'backupserver'

Create key on liveserver:

ssh-keygen -t dsa -b 2048 -f /root/rsync.key

Do not type in a pass

Cat the file that is created into //backupserver/root/.ssh/authorized_keys

You should then be albe to ssh root\@backupserver from liveserver without requiring a pass, if it still asks for pass use the -i param to force it to use the key.

Create a new file in /etc/cron.d to run the backup, the following runs a mysql backup every day at 2am and then rsyncs it to the backup server every day at 5am:

0 2 * * * root /usr/local/bin/
0       5       *       *       *       root    /usr/bin/rsync -azue "ssh -i /root/rsync.key" /var/backup/mysql backupserver:/backups/mysql/wiki_intranet

thats it!