Ever wondered how you can create a backup of your Ubuntu Installation with all the applications you installed which you 've collected after reading articles like this on Internet along with your home folder with all your documents and user settings such as custom icons, themes, plymouth boot splash, grub splash screen etc.,? or how you can make a customized version of your Ubuntu installation with the applications you need and clone it to the other machines in your office, without doing all the downloads and add PPA stuff etc on every single machine ?, or redistribute your custom build to your friends who don't have high internet bandwidth to download all the application they need ? Or just flaunt your customized Linux Distro (with your name and customized branding) within your circle and become a cool geek ?

Then Remastersys is the tool you are searching for.
Remastersys is a tool that can be used to do 2 things with an existing Debian, Ubuntu or derivative installation.
  1. It can make a full system backup including personal data to a live cd or dvd that you can use anywhere and install.
  2. It can make a distributable copy you can share with friends.  This will not have any of your personal user data in it.
Currently there is a size limitation of 4GB imposed by the genisomage tool in Ubuntu and Debian. So you need to exclude the media files etc., from your back up to make space for the packages you need most.

Remastersys is not available by default in Ubuntu apt repositories, you need to manually add the repositories in sources.list file.
  • $ sudo gedit /etc/apt/sources.list
now append the following lines in the sources.list file (as per your distribution)
For Gutsy and Earlier - up to version 2.0.11-1
# Remastersys
deb http://www.remastersys.com/repository remastersys/

For Hardy and Newer with original grub - version 2.0.12-1 and up
# Remastersys
deb http://www.remastersys.com/repository ubuntu/

For Karmic with grub2 - version 2.0.13-1 and up
# Remastersys
deb http://www.remastersys.com/repository karmic/

For Lucid and Newer - version 3.0.0-1
# Remastersys for Lucid and newer
deb http://www.remastersys.com/repository lucid/
For version 3.0.1-1 in versions Lucid or later you need to add the signed repositories.

As root, download and apply the repository gpg key.
wget -O - http://www.remastersys.com/ubuntu/remastersys.gpg.key | apt-key add -
then append the following in sources.list (according your distribution version)

#Remastersys Lucid
deb http://www.remastersys.com/ubuntu lucid main

#Remastersys Maverick
deb http://www.remastersys.com/ubuntu maverick main

#Remastersys Natty
deb http://www.remastersys.com/ubuntu natty main

#Remastersys Oneiric
deb http://www.remastersys.com/ubuntu oneiric main
 update the apt repositories
  • $ sudo apt-get update
Now you are ready to download and install Remastersys
  • $ sudo apt-get install remastersys

Using Remastersys: 

Following are the screenshots of Remastersys,

You can either choose to create a backup or a customized distribution, select a boot menu picture, boot menu picture for installed environment, custom plymouth theme and give it a cool name for your brand etc.,