Because the source server runs an older version of rsync, rdiff-backup cannot run directly. So we rsync to the destination server first then run rdiff-backup over the local copy. Also, because its a production server, we limit the outgoing speed so as not to compromise the server’s ability to serve.

rossetti@Wakatipu:~$ cat /media/backup/backup-pukohu.sh

#!/bin/bash

SOURCE=laudanum-backup
DEST=/media/backup/pukohu
DESTR=/media/backup/pukohu-rdiff-backup

EXCLUDE=/media/backup/backup-pukohu-exclude.txt
LIMIT=100 # speed limit in kbps
RSYNC=/usr/bin/rsync
RDIFF=/usr/bin/rdiff-backup

cd $DEST

$RSYNC -avvz --delete --delete-excluded --numeric-ids --bwlimit=$LIMIT --exclude-from=$EXCLUDE $SOURCE:/ ./

$RDIFF $DEST $DESTR

$RDIFF --list-increment-sizes $DESTR | mail mr.snow@ww2.houseoflaudanum.com -s "Pukohu backup complete"

Exchange keys to allow automatic login.

rossetti@pukohu:~$ sudo cat /root/.ssh/authorized_keys2

command="rsync --server --sender -vvlogDtprz --bwlimit=100 --numeric-ids . / ",no-port-forwarding,no-X11-forwarding,no-pty ssh-rsa [my-long-rsa-key] == backup@Wakatipu

Configure cron job on the destination server as the `backup` user.

rossetti@Wakatipu:~$ sudo -u backup crontab -e

# m h dom mon dow command
10 2 * * * /media/backup/backup-pukohu.sh >> /media/backup/backup-pukohu.log