Install and configure rsnapshot for central backup (without root privilege)

Download and install RsnapShot
Download the latest package from: http://rsnapshot.org/downloads.html

# wget http://rsnapshot.org/downloads/rsnapshot-1.3.1-1.noarch.rpm
# rpm -Uvh rsnapshot-1.3.1-1.noarch.rpm

Configure public key authentication

– Enable public key authentication with remote hosts with normal user privilege

local# ssh-keygen -t rsa
local# scp id_rsa.pub ssh-remote-server:id_rsa.pub

remote# useradd -c “Backup user” -d /data/home/backup/ backup
remote# su – backup

remote# vi .ssh/authorized_keys

remote# chmod 600 .ssh/authorized_keys

remote# cat id_rsa.pub >> authorized_keys ; rm id_rsa.pub

Add the command allowed to execute in the authorized_keys

command=”/home/backup/validate-rsync.sh”

Create the /home/backup/validate-rsync.sh script with following contents

#!/bin/sh
case “$SSH_ORIGINAL_COMMAND” in
  *\&*)
    echo “Rejected 1”
    ;;
  *\;*)
    echo “Rejected 2”
    ;;
    rsync*)
    $SSH_ORIGINAL_COMMAND
    ;;
  *true*)
    echo $SSH_ORIGINAL_COMMAND
    ;;
  *)
    echo “Rejected 3”
    ;;
esac

$ chmod 700 validate-rsync.sh

Create the rsync wrapper script

$ cat  > /usr/local/bin/rsync_wrapper.sh

#!/bin/sh
/usr/bin/sudo /usr/bin/rsync “$@”;

# chmod 755 /usr/local/bin/rsync_wrapper.sh

This steps will basically force the ssh connection to execute the rsync as sudo

Grant user to execute rsync as root

backup    ALL=(root) NOPASSWD: /usr/bin/rsync

Configure Rsnapshot

master# cp /etc/rsnapshot.conf.default /etc/rsnapshot.conf

Configure path for cp, rsync, ssh, logger, du etc

set link_dest = 1

change rsync_long_args like

rsync_long_args –rsync-path=rsync_wrapper.sh –delete –numeric-ids –relative –delete-excluded

If you require daily backup for a week,

interval daily 7

More details are on the how to section for rsnapshot website
http://rsnapshot.org/howto/1.2/rsnapshot-HOWTO.en.html

Configure the hosts and file system to backup

backup      backup@remotehost:/etc/     remotehost/

./arun