Ubuntu. Simple backup that works.

UPDATE 10.08.2009, please read comment at foot of this post

Having recently been let down by mondorestore in Gutsy (see below) I have been researching a new backup strategy. I didn’t want to again leave myself trusting in a tool which lets you down when you really need it, so the stategy had to use readily available and trustworthy software. The solution I have decided upon and tested by doing a complete restore is as follows:

Backing up.
Firstly you need to copy your home directory using sudo grsync (preserve time, owner, permissions and group) or

sudo rsync -r -t -p -o -g -v --progress -l /home/ /media/disk/home/

Keep a copy of this somewhere so that you can find it when your system dies ie on an external drive. Sync it regularly, rsync will only update changes to the original so after the first copy has been made, updates usually only require a few seconds.

Then make a list of all of the packages in your installation using the command

sudo dpkg --get-selections | grep '[[:space:]]install$' | \awk '{print $1}' > package_list

Copy this file together with /etc/apt/sources.list to the same medium you have used for your /home/ directory backup.

You could initiate a cron job to keep this list up-to-date using by putting the following script in /etc/cron/dailypackage_list and making it executable.

#!/bin/sh
sudo dpkg --get-selections | grep '[[:space:]]install$' | \awk '{print $1}' > package_list

Restoring.
First boot the live cd and install Ubuntu.

After Ubuntu has rebooted to the HD version set up your restricted drivers for your graphics card if applicable, there is no need to reboot yet. Then replace the existing sources list with the one from your lost system. assuming that it is on an external disk (together with the /home/ directory) you would use

sudo mv /media/disk/sources.list /etc/apt/sources.list
sudo apt-get update

Then update the packages using:

cat /media/disc/package.list | xargs sudo apt-get install

If you are using some unauthorized packages you will get the following warning

“WARNING: The following packages cannot be authenticated!
libxxx libxx libx xxxplayer
skype-common skype xxxcodecs
Install these packages without verification [y/N]? E: Some packages could not be authenticated”

for some reason you cannot answer yes or no to this, it’s a bug. So simply install all of these packages using

sudo apt-get install libxxx libxx libx xxxplayer skype-common skype xxxcodecs

When that has completed run

cat /media/disc/package.list | xargs sudo apt-get install

again and this time it should complete without problems.

Now copy your /home directory to the new system using sudo grsync (preserve time, owner, permissions and group) or

sudo rsync -r -t -p -o -g -v --progress -l /media/disk/home/ /home/

That’s it! You need to reboot and your system should be exactly as it was. I have tested this three times without problems.

UPDATE 10.08.2009
The method of building and restoring a list of installed packages described above no longer works. Instead to build the list use:
sudo dpkg --get-selections > package.list
To restore the packages use:
sudo dpkg --set-selections < package.list
sudo apt-get dselect-upgrade