Howtoforge posted a guide about backup an Ubuntu 8.10 system with SystemImager

SystemImager lets you create images of your Linux installations. Today do so, you need an image server (should have enough disk space to store your images) and a so-called golden client (i.e., the system of which you want to make an image). This means that you have to install some software on your image server and on your golden client in order to run SystemImager. This tutorial shows how to install a SystemImager server and a SystemImager client, both using Ubuntu 8.10, and how to create/update/restore/delete images.

How To Back Up An Ubuntu 8.10 System With SystemImager