Rdiff‑image
A backup system for hosts in the cloud

Overview

The rdiff‑image tools is a backup solution aimed at hosts running on a virtual machine somewhere in the cloud. It leverages the backup to provide a couple of other features useful to open source style maintenance of the host.

• It maintains two geographically and administratively separated copies of the backup. One is on the host, the other is a set of backups (eg 7 daily, 5 weekly, 6 monthly) on Amazon's S3.
• It uses rdiff to create differential backups that both minimise S3 costs and make downloading the latest set of changes to the host relatively fast.
• It can create a sanitised backup - ie a backup with confidential information in it replaced with so the restored image still boots. Eg, all passwords in /etc/shadow become "x". This allows for a form open source sysadmin'ing of the image while still keeping confidentiality.
• The unsanitised version of the sanitised data can be put in a separate backup that is encrypted with multiple GPG keys.
• Tools are provided to boot the backup in a chroot. This makes it both easy to move hosts quickly in the face of disaster, and to develop and test changes to the host offline.

As an indication of how much backing up to S3 costs, backing up a 4 Gib Debian Lenny host used by a Linux User Group to provide mailing lists, wiki, issue tracking, and planet feeds to members costs around USD$0.70 a month. It does hourly backups, and keeps a mixture of hourly, daily, weekly, monthly and bi-annual backups going back 3 years.

Download

Rdiff‑image is available in the following formats:

In the packaged versions, the rdiff-image-get and rdiff-image-snap programs have been packaged separately.

Documentation

Read it roughly in this order:

• README.txt,
• rdiff‑image‑cron(1),
• rdiff‑image‑get(1),
• rdiff‑image‑boot(1),
• rdiff‑image.conf(5),
• rdiff‑image‑tarutil(1),
• rdiff‑image‑backup(1),
• rdiff‑image‑s3(1).
   
• Example configuration file:
  rdiff‑image.conf.
   
• And the ring-in:
  rdiff‑image‑snap(1).
   
• And the relase notes:
  ChangeLog.txt.

Copyright and License

Rdiff-image tools is copyright © 2009,2010,2011 Russell Stuart.

This program and the accompanying materials are made available under the terms of the Eclipse Public License v1.0 which accompanies this distribution, and is available at http://www.eclipse.org/legal/epl‑v10.html.

Russell Stuart, 2006‑Jan‑09. Email: .