Live CD Customization From Scratch


This procedure works and can create a bootable Ubuntu LiveCd (along with the automatic hardware detection and configuration) from scratch. You do not need to start from a pre-existing LiveCd.


You may wish to create an Ubuntu Remix and distribute it as a LiveCd. Here is a way to do that without having to start from an existing Ubuntu Desktop Cd.






There are three different areas to think about; the host system, the disk image and the chroot.




The Host System


This refers to the Ubuntu desktop you are running, the one the customised LiveCd is being built on. You will need to install the syslinux, squashfs-tools and genisoimage packages to be able to build the LiveCd Remix using the current system.




The Disk Image


The disk image is a folder that we will burn to Cd. Just create a new folder to be the Disk-Image-Folder. The isolinux bootloader binary (taken from the syslinux package) needs to be copied onto the disk image so it will go into the disk image folder for now. The isolinux configuration file, which will allow the Cd to show a boot-menu at boot time, needs to be copied into there too. You will also copy the kernel from the chroot onto the disk image (folder).


The disk image will be created in the host environment, outside of the chroot.




The ChRoot Environment


This is the system that will eventually run from the disk. It does not need a kernel, nor a boot-loader unless you are planning on installing it back onto a hard disk (using Ubiquity). The Casper package needs to be installed into the chroot. Casper is what allows the Live System to perform hardware autoconfiguration and run from a live environment. Installing the Casper package will update the kernel’s initrd to perform these tasks. The kernel that is installed into the chroot will be copied out from the chroot and put into the disk image.


The chroot will end up inside the disk image in the form of a squashed (compressed) file. For right now, it will be just another folder on your host system.


The basic steps are to


  1. Create a chroot and install your packages there.
  2. Compress the chroot system into a file.
  3. Create and configure the disk image which will have the bootloader (isolinux), the kernel, the compressed file-system image and some other stuff.
  4. Burn the Cd and test it out.




Make the ChRoot Environment


From a command-line install debootstrap on the host system. Then make a new folder “work” and inside that make another directory “chroot”. Then run debootstrap


Note: The version of Debootstrap for a release of ubuntu does not contain the files to bootstrap the next Ubuntu release. For example, you cannot bootstrap Karmic on an Intrepid system without intalling Karmic’s debootstrap package. Find the version of debootstrap you need here and install it using dpkg. The debootstrap package doesn’t depend on any other packages and so installing it “by hand” will not cause any problems on your system.





$VERSION above should be replaced with whatever you have obtained. Likewise, $RELEASE is the version of Ubuntu you intend to build an ISO for. $ARCH is the target processor architecture; most of the time, using i386 would be safe. x86_64 is one of the other possible options.


The code above creates a directory called work, with a chroot directory inside it. The debootstrap command installs a bare Ubuntu system into work/chroot.


If downloading from the main archive is slow, use one of the alternatives from this list of mirrors by adding the URL to the end of the debootstrap command, otherwise the archive will be used by default.


Note: If you want to build a newer release of Ubuntu which you cannot bootstrap, for example oneiric:





It is important to install custom applications such as MySQL after linux-generic is installed because such applications require kernel modules for post-install configurations.


If you are planning on installing anything using the package desktop-base (xfce4 for instance), you will also need to bind your /dev to the chroot as well (not just devpts). Otherwise, grube-probe will error out and you won’t be able to finish the installations. Replace /path/to/chroot/dev with your respective chroot.





Now copy the system files so you can get some internet in the chroot.





Note: If you are bootstrapping a release of Ubuntu other then the release you are currently running you should substitute the ‘sudo cp /etc/apt/sources.list chroot/etc/apt/sources.list’ command with the following.





For example if you are running precise and you are bootstrapping oneiric the command would be:



You may edit the sources.list in the chroot to add a line from a PPA, if you need. You will need to add the PPA’s key to your chroot’s package manager. On the PPA’s overview page you’ll see the PPA’s OpenPGP key id. It’ll look something like this: 1024/12345678. Copy it, or make a note of, the portion after the slash, e.g: 12345678. This key will be added once we enter the chroot.


Important: Make a backup copy of /sbin/initctl this next step will delete this file. There is a problem with 10.04 upstart package not containing /sbin/initctl.distrib and even after you update upstart the directions for leaving the chroot do not seem to restore this file.





There is a current (for Karmic, Lucid, …, Precise) issue with services running in a chroot:


A workaround is to link /sbin/initctl to /bin/true.





Upgrade packages if you want:





Install packages needed for Live System:



Before Maverick, discover named to discover1. Adjust the preceding lines accordingly.


If you make Lucid Lynx (10.04) base Live system you need install grub2 plymouth-x11 packages:



Jaunty Jackalope (9.04) seems to hang on the configuration of the network interfaces unless network-manager is installed. This is no longer a problem in Karmic 9.10.





Next, you may install more packages as you like, assuming you have the legal rights to redistribute the packages. This is where you build your custom system using packages from the Ubuntu archives.




Graphical installer, optional step


The customised system can be set-up to allow it to be installed onto machines rather than only ever being a LiveCd. Simply install the Ubiquity packages and an appropriate desktop environment with a window manager. This step is optional and only needed if you want to allow your customised Ubuntu system to be installed on other computers.




For the Gtk front-end







For the Qt front-end







Cleanup the ChRoot Environment


If you installed software, be sure to run



Before exiting the chroot, remove the diversion:


Earlier this guide asked you to make a backup copy of /sbin/initctl. If the following command does not restore this file, then restore from the backup copy you made.





Remove upgraded, old linux-kernels if more than one:





Then just clean up.





If you also bound your /dev to the chroot, you should unbind that.





So far, you have entered the chroot and installed packages, then cleaned up and left.




Create the Cd Image Directory and Populate it


There are 4 packages that need to be installed on the Host System which provide the tools to make the Cd image. Syslinux contains isolinux which makes the Cd bootable. Squashfs-tools will compress the image. Genisoimage provides mkisofs tool to turn a directory into a CD image. So install syslinux, squashfs-tools, mkisofs and sbm.



This next command makes the image directory and the 3 required subdirectories.



A. You will need a kernel and an initrd that was built with the Casper scripts. Grab them from your chroot. Use the current version. Note that before 9.10, the initrd was in gz not lz format…



B. If you have a problem with vmlinuz and initrd copying – maybe you have more than one from these files – you can using following commands:



You need the isolinux and memtest binaries.







Boot Instructions for the Remix User


To give some boot-time instructions to the user create an isolinux.txt file in image/isolinux, for example:





Splash Screen


A graphic can be displayed at boot time, but it is optional. The example text above requires a special character along with the file name of the splash image (splash.rle). To create that character, do the following use the following command:





and then edit the emptyfile with any text editor. Add the file name just next to the first character and add the text you want to display at boot time beneath it and save the file as “isolinux.txt”


To create the splash.rle file, create an image 480 pixels wide. Convert it to 15 colours, indexed (perhaps using GIMP) and “Save As” to change the ending to .bmp which converts the image to a bitmap format. Then install the “netpbm” package and run





Boot-loader Configuration


Create an isolinux.cfg file in image/isolinux/ to provide configuration settings for the boot-loader. Please read syslinux.doc which should be on the host machine in /usr/share/doc/syslinux to find out about the configuration options available on the current set-up. Here is an example of what could be in the file:



Don’t forget to pick the correct extension for your initrd (initrd.gz or initrd.lz). Now the CD should be able to boot, at least it will be after the image is burned Wink ;)




Create manifest:







Compress the chroot


If this Customised Remix is to potentially be installed on some systems then the /boot folder will be needed. To allow the Customised Cd to be an installer Cd, compress the entire chroot folder with this command:



Then write the filesystem.size file, which is needed by the installer:



However, if it is not going to be installed and is ‘only’ meant as a LiveCD then the /boot folder can be excluded to save space on your iso image. The live system boots from outside the chroot and so the /boot folder is not used.



It is important to note that if you are building a Karmic LiveCd on an earlier system, you will need the squashfs-tools package from Karmic or the LiveCD will not boot.




Create diskdefines










Recognition as an Ubuntu Remix


Create an empty file named “ubuntu” and a hidden “.disk” folder. This is needed to make the USB Creator work with this custom iso image. Without this the image will still boot but the USB creator will not recognize the image as an Ubuntu CD and refuse to use it. Also, create the following files with the pertinent information:





Calculate MD5





This calculates the md5sum of everything in the image folder, except the file named md5sum.txt.




Create ISO Image for a LiveCD


Create iso from the image directory using the command-line



The file will be automatically created. You may test your image through virtualbox-ose instead of rebooting your real system if you wish.




Make a bootable USB image


The USB-Creator works properly with the iso image that has been created so long as the hidden “.disk” folder and its contents are present. If you prefer to do it “by hand”, you can put your live system onto a USB drive yourself. Follow these six steps to do so. You can use these steps to put an existing LiveCd onto a Usb bootable device.




FAT16 file-system (Windows)


1. Prepare your work area:



2. Create a loop device with a fat16 file-system. Use whatever size you need to fit your image; in this case it’s a 200Mb sparse file. A sparse file is a file that is bigger than the actual number of bytes it takes up on the disk.



3. Two options here;


3a Mount the Cd-Rom iso image and your new file-system:



3b Just use the “image” folder instead of mounting the iso image. This is useful if you don’t want to make anything other than a Usb image from scratch (You don’t have to make a Cd iso image if you don’t need it)



4. Copy the files



5. Change the location of the boot-loader and its configuration file and make it bootable (For fat16 file-system (default))



6. Pack it up



To install onto a usb drive. Insert the drive and identify it’s mount-point, for example /dev/sdc. Ensure that the device has a partition table on it and run





Ext2 file-system (proper Linux)


An ext2 file-system is useful in that it can hold larger files and the boot-loader can support relative symlinks. Follow the same steps as above, but substitute the instructions in steps 2 & 5


2. Create an ext2 file-system instead of FAT16, obviously.



5. It needs to be made bootable *before* unmounting.





Partitioning your Usb device


A persistent home can be included within a file instead of a partition. If you want to use a whole partition, do the following.


The Usb image can be installed to any partition on the device. Just make sure that partition is the only one that is marked as bootable. You can partition your Usb storage device to contain the LiveUsb image as well as a storage partition. You can use the storage partition to:


– keep a small amount of recovered files.


– create a persistent home.


– or you can use it as swap space.


To partition your device, see HowtoPartition.


If the storage partition is located after the LiveUsb image partition then Windows won’t be able to see it. This is not a problem since you can create the storage partition first and put the live image at the end of the drive. Just make the LiveUsb image partition the only partition flagged as bootable.


When the drive boots the bootable partition will be used and you are good to go. The LiveUsb image’s partition won’t be seen by Windows.






If the device does not boot, you may need to install an MBR onto the device.



and try again.




Persistent Data


Create an ext2, ext3 or ext4 partition named “casper-rw” as a separate partition and append the word “persistent” to your “append” line configuration and all your session data will be stored there. You will be able to keep your changes between boots.





To Do


-Graphical boot






If you have any comments or questions, please feel free to add them here.





I wrote some instructions detailing how to create an Ubuntu Live CD from scratch with debian’s live-helper scripts: Tested on an x86_64 jaunty host for an i386 jaunty target CD.







Hi, I have a question on this guide. The remix after going through these step does not include Gnome Desktop, right? If so, can someone provide me the package name to the Gnome Desktop?


Thks Alan Chen.





The ubuntu-desktop package is based on gnome. If you try to install it with apt-get it will resolve all the dependencies and provide a list. Before installing, it will prompt you and then you can quit. Review the list and you may find the packages you need.




I’d like a live-cd that requires login and does not provide root access without a password of my choosing. Is this possible?




I guess that Casper can do that. Look in the Casper configurations.Perhaps you need to create the user and password while making the chroot, then tell Casper to only use that user? – Andrew





Andrew et al,


I’m not sure that the instructions added here for the issue with running services in the chroot in Karmic are quite right. I say this because I used them today and it resulted in removing the following files: /sbin/start, /sbin/stop, /sbin/initctl. The commands used for removing the diversion did not restore them, and I had to manually reinstall them using a deb file. – Josh







I have made all as is written in this instruction. After loading from a disk I get to live cd command line. How I can start installation?





How can I set the keyboard language for the console and X? Currently I can make the livecd without problem but the kbd language is always en. Tnx in advance.







People interested in a graphical environment read tasksel documentation.


This command show a list of all live CD/DVD tasks (groups of software)





and this other the list of packages in the ubuntu-live task





Carles Barreda





Hi, I’m working on a unnattended install CD using Ubuntu Lucid 10.04, and I found that if you erase /sbin/initctl the automatic install doesn’t run. Also the instruction to generate the initctl using dpkg-divert is not working. So be careful…





When I follow this guide using 10.04. After the system boots it seems casper wants to run gdm. However, nowhere in this guide were there instructions for installing gdm and a window manager. Which is exactly what I want. The problem is that casper does not setup any ttys for me. How can I get casper todo this?





How do I install debian-installer is the same as in the alternate-cd, get it to start after instead of the live cd?







Is it possible to make an HD install from the CD/DVD that has no /pool and /dists folders? I start installation and AptSetup gives me error 127 trying to read the CD pool contents. There’s nothing said about that here. As far as I understand this method uses the current (up to date) packages, so we have to grab the cd repo packages from the net repo also if we don’t want to break dependencies.





Pry: If you get an error 127: after install ubiquity open chrooted environment following file:



and uncomment following line: about 136



(put an # sign):



save and test it. If you have an generated LiveCd you can do it in booted Ubuntu Live environment too. Sevoir





Yet another question. Is it possible to get the package names to be excluded from the HD install (the difference between filesystem.manifest and filesystem.manifest-desktop files) ? It doesn’t seem to be a good idea trying to figure out what to exclude for the next release.







Successfully completed this great guide! Thanks to everyone who contributed. Now I’m curious, after having followed this, tested out Reconstructor (meh, not worth $5 in my opinion), and other variants… at what point in this guide could one make some sort of a backup, to start a new build, without having to download the base packages and such? I am assuming after the debootstrap runs? Could I just back up the chroot folder and in the future continue from there with the backup? I’m going to try this, but I want to be certain that there aren’t any ‘gotchas’ with this method.




One possible answer might be another guide in this series



So, the Cd itself can be considered a back-up stage to be developed from! Smile :)





I just created a bootable/live usb drive with ubuntu 11.04 on it. the problem is that the drive is 16 gigs, but the program I used to create the live usb only allowed me to allocate 4 gigs of extra space (that is space above the space needed for Ubuntu). So I would like to make the extra space much larger perhaps even allow it to fill the whole drive. Is it possible to resize this? and if so how?


Thanks, Daniel Kimbro.



Interesting… I’ve gone through this procedure a couple of times now. It’s awesome! What I don’t get though is, something else is happening. If you make changes in /etc/init, those changes won’t show up when you boot into the live environment.


I was even more surprised when I found that /home/ubuntu doesn’t exist. Assuming this is something Casper does (given that it also takes care of persistent data which gets mounted as /home), where does it store this information?


Regards, Nevyn Hira.





It looks like the sbm package existed in natty but has since been eliminated. Does anyone know if a separate package needs to be installed in precise or oneiric? I will forge ahead and report back either way on my results.


Thanks, erixoltan





This howto is excellent! I am, however, having a problem getting my wireless networking credentials onto the custom image. I’ve tried to do this simply by copying over /etc/NetworkManager/system-connections/* but this is causing problems. When I boot to the image, it says the installer encountered an “unrecoverable error” and then goes to a desktop session without any problem.


The specific error is in /usr/lib/ubiquity/bin/ubiquity:





Any help would be appreciated. Thanks!


Live CD Customization


Why customize LiveCDs

You may wish to customise the Ubuntu Desktop LiveCd to:

  • make your own Linux / Ubuntu distribution
  • show off a particular application
  • localise to a certain language
  • remove software packages
  • add software packages
  • update software packages
  • change system defaults (theme, icons, desktop background, panels, browser homepage, etc)


How to Customise the Ubuntu Desktop CD

The easiest way to create a custom LiveCD is to use Ubuntu Customization Kit. What follows is the manual way of accomplishing the same.

You might also want to create a LiveCD from an existing installation; in this case, Remastersys is for you.

IconsPage/warning.png This guide is for the Desktop LiveCd; there is another page referring to customisation of the Alternative Install Cd & the Server Install Cd. Also, there is a guide on how to create a LiveCd without using an existing LiveCd.


System Requirements

  • At least 3-5 GB of free space
  • At least 512 MB RAM and 1 GB swap (recommended)
  • squashfs-tools
  • genisoimage, which provides mkisofs
  • An Ubuntu kernel with squashfs support (present in Ubuntu 6.06 and later)
  • QEMU/KVM, VirtualBox or VMware for testing (optional)

IconsPage/warning.png When customizing 9.10 Karmic Koala (or later) in an 9.04 Jaunty Jackalope (or earlier) environment, squashfs-tools must be updated to version 4.0. Conversely, the version of squashfs-tools in Ubuntu 9.10 is not compatible with earlier versions of Ubuntu.

IconsPage/warning.png The architecture (Amd64 or i386) to be stored on the LiveCD should be the same as the architecture used to perform the customization, or the LiveCD may not run. It is not trivial to customize an AMD64 LiveCD using an i386 operating system, for example.


Install pre-requisities

  • Make sure that you have installed the needed tools



Obtain the base system

Note: the example shown here uses the ubuntu-9.04-desktop-i386.iso Desktop CD. Replace it with the name of your iso. For example, if you have a ubuntu-11.04-desktop-i386.iso image, the command:

would be changed to:

  • Move or copy it into an empty directory



Extract the CD .iso contents

Mount the Desktop .iso

Extract .iso contents into dir ‘extract-cd’


Extract the Desktop system

Extract the SquashFS filesystem


Prepare and chroot

If you need the network connection within chroot

Depending on your configuration, you may also need to copy the hosts file


(these mount important directories of your host system – if you later decide to delete the edit/ directory, then make sure to unmount before doing so, otherwise your host system will become unusable at least temporarily until reboot)

To avoid locale issues and in order to import GPG keys







In 9.10, before installing or upgrading packages you need to run






To view installed packages by size

When you want to remove packages remember to use purge


Custom Background for GNOME

Generally background files are located in /usr/share/backgrounds. Copy your png file there, adjust owner and file access, and edit the files:

  1. /usr/share/gnome-background-properties/ubuntu-wallpapers.xml and
  2. /usr/share/gconf/defaults/16_ubuntu-wallpapers or other files in the same directory. by changing the string /usr/share/backgrounds/warty-final-ubuntu.png to point to your file

Eventually change or add attributes to other configuration files such as: /var/lib/gconf/debian.defaults/%gconf-tree.xml or /etc/gconf/gconf.xml.defaults/%gconf-tree.xml).

Historical: More for Dapper…


Change gconf values (fonts, panels etc.)

To make any change on the gconf attributes you must add the value that you want in the file /etc/gconf/gconf.xml.defaults/%gconf-tree.xml. Adding a value in that file will change the default values of Gnome or other applications, so you can change fonts, backgrounds, themes, cursors etc.

Instead of editing the file with gedit or another text editor, you can use the gconftool-2, under the chroot environment, running the following line:

where string, yourkey and yourvalue must be the type, key and value that you want to change…


Making several gconf changes

Editing gconf by setting each value separately takes too much time. There is a better way:

Make a test user and adjust the settings as you wish. Run


and then, in the chroot environment, run


This way you can import the whole branch, e.g. /apps/panel – all settings for Gnome’s panels. Note that this way you import not only the keys, but also their descriptions, so all GConf descriptions will be changed to the language which was set for the test user, and there will be no way to safely change them back. Some programs (for example, keyboard shortcuts in Preferences menu) use descriptions from GConf.


Setting regional defaults


Change default language of gfxboot

This customization must be done outside the chroot.


Change “fi” to your preferred locale. Note that this does not change which languages are available in the F2 menu. For more info about gfxboot customization, see Ubuntu Customization Kit.

  • A other way to change the default language of gfxboot without rebuild the packages is to create a file name lang in the isolinux directory containing your locale’s name.


Change default keyboard

In 12.04, changing the default keyboard for a live boot is not as obvious as it used to be in 10.04 and earlier. As an example, if you want to keep the default language as English but set the default keyboard to “GB”, you are going to have to edit the file /usr/lib/ubiquity/ubiquity/ If you look at the hard-coded defaults table at around line 620 it should be fairly obvious what’s going on…


You can se the default keymap for your default language by editing this table, but remember that if you update the ubiquity package on your image then any changes will be clobbered.

Also note this only works for X. To set the console keyboard:



Customization limits

After customization make sure that there are no users with an UID == 999. Otherwise your image won’t boot because no initial user is available (see /usr/share/initramfs-tools/scripts/casper-bottom/25adduser, -> ‘db_set passwd/user-uid 999’). This may happen, for example, after installing VirtualBox/GuestAdditions

While in chroot:


If you get any hits, try changing the uid:



Miscellaneous Defaults

You may wish to edit the files in /etc/default to change system behavior at startup. You might also edit /etc/profile, /etc/bash.bashrc, and /etc/bash_completion to change login settings for all users on the system. You cannot directly edit defaults for the live cd user (e.g., casper, ubuntu, or user) since that account is created at boot time. You can directly edit root’s default files (/root in the chroot environment).

If you wish to change the default timezone used by the live cd, run:


If you have added a locale and wish to make it the default, update /etc/default/locale. You may have to compile the locale:


These changes must be made as root in the chroot environment.


Advanced Customizations


Live CD Kernel

If you want to customize further the boot process, you can change the livecd kernel, by copying the vmlinuz and initrd you want in place of the ones you find in extract-cd/casper.


Note that the initial ramdisk filename for newer releases (since 9.10) is casper/initrd.lz (not .gz).


Removing the (Casper) Autologin

The autologin feature of the Jaunty/9.04 live CD is a bit of an on-the-fly boot-hack. After extracting the initrd.gz, you need to edit the casper-bottom/25configure_init script and then recreate the initrd.gz file, replacing the original in extract-cd/casper. The process to do so goes like this:


Now look for line 25 which has the conditional statement to test $USERNAME.

Line 25 performs a conditional evaluation and if it evaluates to true, it will execute the code within the if block. The if block contains code to modify files used in the boot process to create the live cd autologin.

To disable the autologin feature, Remove $USERNAME, but just leave the quotes. The -n modifier tests the $USERNAME string to see if it’s length is non-zero. By removing the variable, and leaving two double quotes, this statement evaluates to false because the two double quotes effectively make a zero-byte string. Be sure to leave no whitespace between the quotes because whitespace will make the evaluation true and execution wil fall into the if block.

After making the change, line 25 will look like this:

Save the file and quit the editor. Then, from extract-cd/casper/tempdir run the following command to re-create the initrd.gz file. There are other methods for re-creating the initrd.gz file on this page which may work also.:


This will create a new initrd.gz file with no auto login. You can then continue to remaster the CD as described on this page. Be sure to create a user and password to login with before you remaster the cd. If you do not, you will not be able to login after booting!

Also, I have read a few articles mentioning that Karmic (9.10) uses initrd.lz instead of initrd.gz. I do not know if this is true, but should mention it in case you are not getting the expected results. To unpack the initrd.lz file, you need to do this:


And to re-create the initrd.lz file:


Boot init

You have to edit the files in edit/usr/share/initramfs-tools/scripts/casper-bottom/* For example you can change the hostname or the livecd user.



and edit the username or hostname


to edit even the livecd user’s password.

If you’re customizing 10.04, you need to edit variables in /etc/casper.conf for the user and host names instead of modifying the scripts

P.S. in order to obtain an encrypted password, you have to use the mkpasswd program that’s shipped with whois package!


Rebuilding initrd

After you’ve modified the kernel, init scripts or added new kernel modules, you need to rebuild the initrd.gz file and substitute it into the casper directory.


(replace the kernel version with the one that the CD will boot with – this can be found in edit/lib/modules) *** do I need to mount proc, sys, devpts after chroot here ? Gordon

Exit from the chroot jail and move this file to extract-cd/casper:




Be sure to remove any temporary files which are no longer needed, as space on a CD is limited. A classic example is downloaded package files, which can be cleaned out using:

Or delete temporary files

Or delete hosts file

Or nameserver settings

If you installed software, be sure to run




from within the chroot environment.

now umount (unmount) special filesystems and exit chroot


  • Note: if “umount /proc” command fails, “umount -lf /proc” will be used to retry automatically.


Producing the CD image


Assembling the file system

Regenerate manifest

Compress filesystem

  • Note: The -nolzma option is only available from Hardy , and was removed in Karmic. Also, the squashfs has to be generated using a version of mksquashfs that is compatible with the kernel used on the CD you are customizing. For example, you cannot generate a jaunty squashfs on karmic, as the jaunty kernel is not able to mount a squashfs prepared using mksquashfs from karmic.

For slightly higher compression at the cost of compression time, you can increase the block size:

For a highest possible compression at the cost of compression time, you may use the xz method and is better exclude the edit/boot directory altogether:

Update the filesystem.size file, which is needed by the installer:

Set an image name in extract-cd/README.diskdefines

(you can use “sudo nano extract-cd/README.diskdefines” if you have difficulties understanding vim)

Remove old md5sum.txt and calculate new md5 sums

Create the ISO image


Testing the CD

Test using qemu emulator


Or if you have hardware acceleration for kvm


You can also test with virtualbox-ose, which is free software and available in the Ubuntu universe repository.



Some experience problems virtualizing the iso after changing the livecd linux kernel. If you do, go click F6 when the boot screen is showing. Move the cursor between splash quiet and — and write: all_generic_ide


Burning the image to CD

Simple! Just do



Additional uses for the image

Install Ubuntu from a USB stick

Installation From Image Loaded On Hard Drive



If you have any comments or questions, please feel free to add them here.

If you are answering a question, please rewrite the question into a tip that answers the question. (to help keep things to the point.)

New questions at the bottom (I guess.)

I have created an small Customization Example (named Firebird Live CD) by adding an firebird2.1-superand flamerobin packages (this apply to ubuntu Hardy Heron also it was tested with xubuntu 8.04)


Warning: qemu did not work for me as given in the guide above. Even the normal 8.04 live cd would not boot correctly. Every time, I would get thrown into the ash shell (busybox, initramfs) and while there, a “cat /casper.log” would reveal that it was “Unable to find a medium containing a live filesystem”. Just use virtualbox-ose. It actually works with virtualbox. However, after using apt-get to install virtualbox-ose, I had to run “sudo depmod” again in order for the vboxdrv module to be found by modprobe. Hope that helps!



Warning: Squashfs is currently in development and is thus not finalized as a format. This means you cannot assume a filesystem.squashfs created using the Ubuntu 9.04 version of makesquashfs will be compatible with the squashfs drive an older live CD. I was customizing an Ubuntu 7.10 LiveCD and when testing it always booted it an (initramfs) prompt–the squashfs was not getting mounted as /. I had to build from within an Ubuntu 7.10 chroot to get it to work.


I have created an small Customization Example (named Firebird Live CD) by adding an firebird-super-server and flamerobin packages (this apply to ubuntu dapper drake) I created an updated guide with Ubuntu Festy Fawn also with an iso download for the Firebird/Flamerobin live cd


I have created tool for automatic remastering of live CD images. See .


  • GUI for simple creation of localized CDs (including changing gfxboot and installing language packs)
  • Script for customization of ISO, SquashFS and initrd on live CD. seems to have some nice info. no license that I can see so we would need to ask permission from the author to us its material.


If you want to make the CD boot faster, you might try sorting the files so that they are in the CD in the order that they are accessed:


Great How To. I am having one issue however. I would like to use custom xorg.conf and sources.list files. Any tips on doing this? Thanks.

  • Simply, copy the files to edit/etc/ in the same way (and at the same time) that you copy in the resolv.conf and hosts files.
  • I have found that copying xorg.conf doesn’t work, as the boot-time scripts overwrite it. Besides, you can’t guarantee that a particular xorg.conf will run on all hosts. I’m currently trying to get the binary NVIDIA drivers to work out of the box if an NVIDIA card is present. If I figure out how to fix the xorg.conf, I’ll post it here. —JeremyVisser


I’ve managed to get Synaptic running from within the chroot environment, but it does hang when I try to apply packages. What you do is run “Xnest -ac :1” to get an Xnest server to run on display :1 without access control so anyone can connect to it. Then, in the chroot environment, run “export DISPLAY=:1” to get programs to use the display. Then, type “metacity &” to be able to move windows. Finally, run “synaptic”.

It works fine until you try to apply packages, where it hangs for me. —JeremyVisser


Shouldn’t the mkinitramfs command use the casper scripts, like “mkinitramfs -o initrd.gz 2.6.15-23-386 -d /usr/share/initramfs-tools”?


There are tricks on how you can get to feel the GNOME system in your chroot environment.

1. Copy your xorg.conf in the chrooted “etc/X11/” directory.


2. Create generic devices on your chroot system using MAKEDEV


3. Start X or restart gdm


Supposed you want to make modifications on the Desktop, that will be used by all the new users, just change your $HOME to /etc/skel/ and start gdm or X.


If you want to load all the other stuff GNOME needs (i.e, dbus, avahi, network-manager), just boot as (single-user mode), and start dbus in your chrooted environment.


An example of the whole procedure. (under single-user mode)





I am about to build a new Livecd and have a question: When I change the username, hostname and the user’s password the user login automatically during booting the livesystem. But this is not desired. Is it correct, that I have to enter a password under a Desktop LiveCD when I delet the encrypted password in /usr/share/initramfs-tools/scripts/casper-bottom/10adduser ?


Changing username and password will not change login behaviour, because this is done in /usr/share/initramfs-tools/scripts/casper-bottom/15autologin

Alexander Hosfeld


Having trouble starting a MySQL server from within the chroot jail. Any suggestions?

– Dave


I am trying to make a customized live cd of Kubuntu 6.06 that will be completly preconfigured, so that when the user clicks on the install icon on KDE the installer should do everything by itself, meaning that the installer should not ask any questions to the user.

To do this I am trying to write a preseed file to tell the installer the information that it needs.

The problem is that even with this preseed file I could only tell the installer what is the username that it should use, the rest of the information is simply ignored by the installer.

I must be doing something wrong and would appreciate any and all help given me.

Thanks, Komyg

PS: Should I post my preseed file here?

If the livecd is not going to be used for the purposes of installing what files can be removed? Can the “pool” files containing the .debs be removed too?

– Mike

If I want to put in my LiveCD applications that aren’t in the sources.list (like ooffice 2.2 or perl audio converter), what cain I do?

– Isoldanne

When you’re in the chroot you can install applications just like you would on a live system. If you install from source you can feel free to delete the source tarbal and make folders after you do ‘make install’.

– Bob/Paul


To get desired /etc/X11/xorg.conf one can modify the /usr/bin/dexconf. This script generates xorg.conf automatically in liveCD session according to the booted machine.

For example:


— yotam


I cant do chroot. When i run it a get this error

chroot: cannot run command `/bin/bash’: No such file or directory

Please help me out

  • I had the same problem because the filesystem that I was working on was FAT32 instead of EXT2 or EXT3. Because of that, /bin/bash was not an executable I guess. If that is your case also, then please try again on a partition that is EXT2 or EXT3 (the Linux type of partition). Good luck, –vvim

Hi, I’ve created a simple script to ease remastering the Kubuntu Live CD. It uses aufs to avoid copying all the files back and forth.

Maybe it will be usefull to others too. The script must be run as root.

— Petr Pudlak


I need to know how to configure the live cd so that it does not use SWAP!

Please help me!

— iceman

Hi, I’ve been experiencing problems with aptitude and I’m pretty sure its because I’m doing all this stuff on NTFS partition (according to this thread But I have no other choice,coz’ I’ve got less then 1,7GB on my ext3 partition. Any suggestion ? THX

Error messages I’ve been getting, when trying to install or update aptitude:

“E: Couldn’t make mmap of 25165824 bytes – mmap (19 No such device) W: Unable to munmap E: The package lists or status file could not be parsed or opened.”

-heethen (heethen at centrum dot cz)

I would suggest creating an ext3 filesystem within your NTFS partition. To create the file, type

dd if=/dev/zero of=/mnt/hda1/workspace.img bs=1024 count=$((1024*1024*15))

Where I assumed your NTFS partition was on hda1, and you wanted to call the new filesystem workspace.img (it’s really just a file within NTFS), and that you wanted 15Gb of room to work. (You don’t need that much, but with 15Gb you should have plenty of room.) Then you format the new filesystem with the command

sudo /sbin/mkfs.ext3 /mnt/hda1/workspace.img

then create a mountpoint

sudo mkdir /mnt/workspace

then mount the new filesystem

sudo mount -o loop /mnt/hda1/workspace.img /mnt/workspace

You can then use as much space on the NTFS partition as you want, and have all the benefits of ext3 (like getting the *** thing to work). –Tom

Editing gconf by setting each value separately takes too much time. There is a better way:

Make a test user and adjust the settings as you wish. Run


and then, in the chroot environment, run


This way you can import the whole branch, e.g. /apps/panel – all settings for Gnome’s panels.

—Jacob Popov ubuntu-9.04-desktop-i386.iso


Is there no way to copy the user’s gconf-values to the default gconf-values in the chrooted environment? This would be a lot easier than writing commands.

It took me a long time to find the details for configuring a static IP on the live CD without doing it in the root file system. This enables you to create a few boot options with different static details and a DHCP on but all from the same rootfs.

There is a casper parameter which is in the form:



I think I have discovered how to do this:

1) Edit accordingly /usr/share/initramfs-tools/scripts/casper-bottom/23networking

2) Run update-initramfs -u -k $version

– Robert

In order to get the livecd to boot from a static address found in the /etc/network/interfaces file.

I edit the /etc/network/interfaces file and add a static address for the interface eth0.

edit somepath/isolinux/text.cfg add ip=frommedia after splash

This was a little hard to find. Thanks Robert Nicholas A. Schembi Pittsburgh PA USA


I’ve tried installing adobe flash player but while it installs fine on chroot, and then shows as installed when booting from CD. Firefox thinks it is not installed and I need to install it manually. Anybody come upon a similar problem

I tried to customize Ubuntu Hardy by installing the RT kernel and did the changes as written in the howto… it goes well, but booting in vbox is really slow. What could be the cause? I tried is once again and also in another vbox installation, but still that problem. Would be nice if someone can point me to an solution! thanks in advance see also thread: edit: I think it has something to do with the fact that it is an RT kernel (from Hardy) … Someone with experience with adding custom RT kernels?

I wrote a script to automate the extraction / chroot / regeneration processes: . It has been tested on a jaunty x86_64 host for a jaunty i386 CD image.


To put the default user in the “video” group,



In order to edit a Karmic LiveCD in any release prior to Karmic, it looks like you will need to upgrade squashfs-tools to support SquashFS v4.0:


I installed squashfs-tools_4.0-1 from the Karmic release into my Intrepid installation and it seems to be fine now. Maybe we should update these directions to reflect that?


–John D. Zollo

Hi.. How can I add an a Post Installation script? I mean, I want to execute a script just after the installation process. THis script is simple and set a few things to customize the installation.

Any ideas?

Best Regards

— Alejandro


Hallo, I’m trying to remaster ubuntu 9.10 livecd. I’m following instruction from this page. When I’m trying to boot from customized system it’s seems I can’t login to the system, so I can’t got the system running.

I am following instruction from limitation part about user id. And make sure there are none of users has uid more then 999. But, after making the squashfs file system I got a message that told me about a user with uid 1000. Actually my host system has a user with uid 1000. I’m using this user to remaster ubuntu livecd.

Does my uid (1000) that I used for remastering the livecd make the new live cd can’t login? If it does, how to fix it? Am I must use another user with uid less then 999 to remaster the livecd?

Best Regards


Hello, what is the best way to remaster the Karmic release LiveCD (in VirtualBox) to include all the latest updates (more than 150) including new kernel and udev? The kernel changed from 2.6.31-14 to 2.6.31-16 and also udev.

apt-get autoremove removes the old headers, but I have to purge the old kernel manually (apt-get purge linux-image-2.6.31-14-generic).

The first problem is, update-initramfs -u -k all still runs for the old kernel, too. Only aptitude reinstall udev seems to stop this (depmod -a && dpkg --configure -a && dpkg-reconfigure udev does not help).

The second problem is, how do I prepare initrd and isolinux to run and install from a subdirectory (to create a multi-boot DVD)? The base of the DVD is Ubuntu, so / contains ubuntu-9.10-desktop-i386.iso, /kubuntu contains kubuntu-9.10-desktop-i386.iso and so on. Most things run fine when I introduce the prefix to scripts/casper and /isolinux/text.cfg:


But the prefixed distributions show only an Install Ubuntu 9.10 link on the desktop, not Kubuntu (Xubuntu, LUbuntu, …).

Thanks, René Leonhardt



I was hoping to be able to remaster the Ubuntu Live disc so that I can stick it into almost any computer, have it boot up but NOT go into the GUI, just auto login and run a media player with arguements (like a stream address). Was hoping to be able to make my own easy internet radio appliance. Give old pentium computers with soundcards to businesses and they can play my station on their PA for free!

— Matt


I updated the Karmic Live CD with the latest updates inside chroot using aptitude with update, dist-upgrade, purge linux-image-2.6.31-14-generic, install zsh zsh-doc, install ubuntu-restricted-extras, and enabled DVD playback.

The resulting iso file turned out larger than a CD, and I put it on a USB Disk. The system boots fine, has the latest updates and can play restricted formats ‘out of the box’. When I travel, I can just carry a USB Disk instead of a computer!

All releases including Ubuntu 9.10 Karmic Koala now have newer kernels available via updates. The kernel in the live CD *MUST* match the ones inside squashfs. If it does not, you get strange problems (like the wireless interface not being detected or CDs not being recognized)

i.e. for Karmic

Since Karmic uses initrd.lz, I had to uncompress the .gz file and put it back in .lz format.

To conserve space, you can remove the original initrd files before changing the directory back

Best, Pradeep Sekar

I have a few questions, I am remastering a copy of 9.04 for a community school program i ran into a few problems

#1 how do you remove the option to update to 9.10 in the update manager #2 how do you get the CD to be recongnized in ubiquity installer as the named distro instead of ubuntu 9.04 (when i go to reinstall the softare still says it is a ubuntu 9.04 cd) #3how do you install a new kernel into the live cd and install part, i was able to upgrade it to 28.18 but when i try putting 31 on it …it just wont boot.

#4 i have a repos server, i edit the sources.list but ubuntu repos are still the primary, how do i change that over?

#5 finally, i took out gnome games, and i want to add a list of eduacational games, but i want that as a optional install. (some computers won have game son there) is there a way to add the /.Games folder without actaully having data in it? i tried doing this in the chroot adn root menu and it still does not show up on install…

Thank you



Can anyone tell me how I can take out the option of installing the Live CD at boot. I just want them to be able to use it, not install.



You can edit the boot options in extract-cd/isolinux/text.cfg Delete all lines and sub-lines of a label you don’t like: For example you can delete:

— jancelis

To remove the autologin, you make us work in the extract-cd directory. Does this mean that this process has to be the last one ? Do we have to do it after all the modifications on the edit directory ? Do we have to first create the new user in the chroot ? thx –lsga

I’m having trouble properly adding a repository. How do you add one to a live cd? –Muscovy


Hi, I’m working on a unnattended install CD using Ubuntu Lucid 10.04, and I found that if you erase /sbin/initctl the automatic install doesn’t run. Also the instruction to generate the initctl using dpkg-divert is not working. So be careful…



I customize the live cd and install apache2 , webmin ,,, but how to make it start after the automatic-login ?


I use a version of Ubuntu that does not automatically Start the graphical system (startx command) How can I add that to be run at boot?



I am currently working on a minor update given 10.10 is out. Unfortunately, I got held up and now time has run out. Mainly I wanted to make the scripts more copy/paste friendly. So I added a few env-variables and use those throughout the script. I’ve done the replacements already, but I didn’t get aroud to do some testing.

In the meantime, I’ll dump my current version into the above link to save my work.



aptitude can’t purge packages.

The program ‘aptitude’ can be found in the following packages:

  • aptitude
  • aptitude-gtk (You will have to enable component called ‘universe’)

Try: apt-get install <selected package>


Unable to find a medium containing a live file system (SOLUTION)

When creating a live-usb with Unetbootin from Windows (Vista/7) you sometimes get this error. A friend of mine suggested another solution than all of the above. Create the USB stick with Unetbootin from a Linux (Ubuntu) box and NOT a windows system. Apparently something is different between the two because now my system just boots flawlessly!



Regarding the “Unable to find a medium containing a live file system”–

I had this same problem when trying to install Ubuntu 10.04, 10.10, and 10.10 netbook edition on a netbook using a USB stick. I tried creating all three using 10.10’s boot disk creator, 11.04’s boot disk creator, Unetbootin on 11.04, and Unetbootin on Windows 7. In all cases, I was able to make it to the usb boot menu and would select ‘Install’. The Ubuntu logo would show that it was processing for a while and then fail with the above message in a terminal.

In the end, it wasn’t a problem with the iso or the created USB stick. The USB drive just wasn’t mounted (or would become unmounted after I tell it to go through the ‘Install’ procedure. Since I couldn’t figure out how to boot the usb from the provided terminal, I just tried removing and reinserting the USB drive once I saw the Ubuntu logo and the progress blips.

I was able to get past this problem twice, so far, with this solution.



For all of you semi new maybe not quite as knowledgeable Ubuntu users, as myself, the live CD environment does not utilize all of the typical repositories that it would as if you installed it. You might need to add the particular repository of interest to install a program for your live CD.

For instance, I wanted to create a live CD with dcfldd on it. I had to edit etc/apt/sources.list within the chrooted environment to add the universe repository. I uncommented the following to lines in etc/apt/sources.list to install dcfldd:

Then just updated apt and installed as normal:

Sorry if everyone already knew this. I just figured it may be helpful to users like myself.



Hi Smile :) I’m sure people appreciate comments such as your MrGrant. Otherwise people might feel they are the only ones suffering from something or maybe feel they are to blame.

On a normal LiveCd there is an “installer” icon. DOes anyone know how i can get that icon onto a normal Ubuntu desktop? I have done a full install to a large usb-stick and installed things like “GPartEd” but i definitely miss havign that installer icon & functionality. Regards from Tom Smile :)


I am looking to update or see an update to this guide that addresses a custom launcher on unity. So the idea is once the desktop and unity have resolved to the scree, I can click on a custom launcher with out looking in dash to find it. This message should be replaced with this information, in case someone else beats me to the punch.



I am a total beginner. How do I take my current computer configuration and turn it into a install CD? Thanks!

Nick Smile :) (Sorry if my question sounds dumb)


Hi Nick 🙂
This link might help

but i would avoid it. It’s not dumb, just tricky.

Instead you can back-up all your settings, config files/folders and data by backing up the /home folder. You can move your /home to a new partition to separate your data (including configs and stuff) from the Operating System. That allows you to re-install the OS without messing anything up

It’s even possible to have 2 different Operating Systems sharing the same /home although it’s not recommended.

Better places to ask questions are

and Launchpad
Regards from
Tom Smile :)


I think this entry could be improved by adding some explanation of what we are trying to accomplish with these commands. Pretty much any time it says “you need to use” or “remember to” it would be great to know why. Just my two cents.