The backup tool in the live disk is not complete. It's tricky to install all the necessary components to get the backup working properly. You could simpler backup your
/home folder with the
You can do this by, first mount your destination backup device (which may already be mounted since it's your
Create a backup area for your destination and perform one of these two commands:
$ sudo cp -pvau ~/ /mnt/backupdir/
In the preceding command the
/mnt/backupdir is the backup destination directory where you will be backing up your space. It will create a folder by the your username in the
This space could have been created on a partition off your
Alternatively you could backup your whole '/home` folder with this command:
$ sudo cp -pvau /home /mnt/backupdir/
This command would result in a folder called
/mnt/backupdir/home with your personal home folder under there.
The copy arguments are:
p - preserve ownership and time stamps
v - give a verbose output during the process
a - archive (perform a recursive copy of all files and folders)
u - update files that have changed if they already exist in the destination.
You said you were concerned about during something "radical" which could loose your personal data.
Installing or reinstalling Ubuntu will not touch your
/home folder or any other folders that you created on your installed partition unless you specifically elect the format option during the installation process. As long as you don't put a check mark in format your personal data will be preserved.
It's important to always have backups of your important data. But the install process will advise you that your data will be erased and not recoverable if you select to format. Also if you don't checkmark the format option, it'll still advise you which directorys (the system folders) that will be erased and recreated.