Why customize LiveCDs
You may wish to customise the Ubuntu Desktop LiveCD to:
- make your own 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
This guide is for the Desktop LiveCD. There is another page referring to customisation of the Alternative/Server Install CD. Also, there is a guide on how to create a LiveCD from scratch. This guide is based on customisation from an existing Ubuntu 22.04.1 LTS amd64 LiveCD.
System Requirements
- At least 100GB GB of free disk space
- At least 4GB RAM, much more recommended
xorriso, to compile a new ISO image
squashfs-tools, to unpack and recompile the 'live' filesystem
binwalk for investigating the initramfs file, if updating the boot kernel (optional)
casper files are required for recreating initramfs for updating the boot kernel (optional)
live-boot and live-boot-initramfs-tools if upgrading the boot kernel, as needed to recreate initramfs (optional)
QEMU/KVM, VirtualBox or VMware for testing (optional)
It is strongly recommended that you perform the customisation of a LiveCD from an installed copy of that version of Ubuntu. Some operations in this guide (noted at the relevant point) will likely fail otherwise. For example, to customise from an Ubuntu 22.04.1 LTS AMD64 LiveCD, you should work on an installed copy of Ubuntu from that version. It may well be sensible to perform the update from a dedicated installation or a dedicated virtual machine as a number of operations can be disruptive to the host.
The architecture (amd64 or i386) to be stored on the LiveCD should be the same as the architecture used to perform the customization. It is not trivial to customize an amd64 LiveCD using an i386 operating system, for example. Also, the Ubuntu system you are using to create a custom image should be of the same major release version as that of the target system. Otherwise, the LiveCD may not run, and / or you may get stuck at some point during the customisation process.
Install pre-requisities
- Make sure that you have installed the needed tools. This guide assumes you are going to use QEMU KVM virtualisation and complete all optional tasks.
Update the package lists:
sudo apt-get update
QEMU-KVM and Virtual Machine Manager:
sudo apt-get install apparmor apparmor-utils bridge-utils libvirt-clients libvirt-daemon-system libguestfs-tools qemu-kvm virt-manager
Strict requirements for customisation:
sudo apt-get install binwalk casper genisoimage live-boot live-boot-initramfs-tools squashfs-tools
Note that some of these packages also install dependency packages which are needed, such as xorriso. If you deviate from this guide, you may need to install some additional required packages manually.
Obtain the base system
Download an official Desktop image from http://releases.ubuntu.com
- Create a working folder with the image to work from.
sudo mkdir ~/custom_live_cd sudo mv ubuntu-22.04.1-desktop-amd64.iso ~/custom_live_cd sudo cd ~/custom_live_cd
Note: this example refers to Ubuntu 22.04.1 Desktop. Replace it with the name of your iso. It is strongly recommended at this point that on the host / build machine you upgrade all packages at this point:
sudo apt-get dist-upgrade
Then repeat until all packages are up to date. Following this, clean and autoremove old packages:
sudo apt-get autoremove sudo apt-get clean
Extract the physical DVD .iso contents
sudo mkdir isomount sudo mount -o loop ubuntu-22.04.1-desktop-amd64.iso isomount sudo mkdir extracted
We then copy the files from the mount to a working folder using the rsync command. rsync is a fast copy utility, amongst other things, and the -a switch preserves the time, date and permissions on the files. The --exclude switch excludes the compressed squash file system from the copy.
sudo rsync --exclude=/casper/filesystem.squashfs -a isomount/ extracted
Extract the SquashFS system
We now have a local copy of the DVD file system without the squashfs file, which we will want to work on separately. We extract the squashfs file to a separate local folder:
sudo unsquashfs isomount/casper/filesystem.squashfs sudo mv squashfs-root edit
Prepare and chroot
chroot is an operation that changes the apparent root directory for the current running process and its children. In practice, for present purposes, this lets you work in a copy of a Linux file system you have in a sub-folder and update it, remove and install packages like it was the actual running system using commands like apt-get. In fact, in this guide this is almost the only reason to chroot. Other changes can just be made by amending files.
Unfortunately, significant functionality will be lost on chroot, including network functionality which is likely to be necessary for tasks such as updating and installing packages. You can avoid this issue by just binding /run instead before the chroot, which will pull your host's resolvconf info into the chroot:
sudo mount -o bind /run/ edit/run
Depending on your configuration, you may also need to copy the hosts file
sudo cp /etc/hosts edit/etc/
The following bindings are also necessary. Before chroot:
sudo mount --bind /dev/ edit/dev
Then chroot:
sudo chroot edit
Then bind from within chroot:
mount -t proc none /proc mount -t sysfs none /sys mount -t devpts none /dev/pts
The above commands will mount important directories of your host system to the edit directory. If you later decide to exit from chroot, make sure to unmount all of them before doing so. (See the cleanup chapter below). Otherwise, your host system will become unusable until you reboot it.
Customizations
Apt
The main reason for chrooting into the edit folder is to install, update and remove apt packages, especially for updating the kernel version.
Tasks
To view installed packages by size:
dpkg-query -W --showformat='${Installed-Size}\t${Package}\n' | sort -nr | lessInstalling packages:
sudo apt-get update sudo apt-get install <package1> [<package2>]
When removing packages, use purge:
apt-get purge package-name
It is likely desirable to update all packages to the latest version, including the kernel. If it is desired to update to the latest kernel, both the build machine and the edited environment must have exactly the same kernel version to enable regeneration of the initrd file. If this is not possible, updating the kernel is not recommended. The commands are:
sudo apt-get update sudo apt-get dist-upgrade
Note - if the kernel is updated you will need to follow the instructions for a kernel update in the separate section below, otherwise you may have obsolete files bloating the image, and boot may fail.
The number of package sources available on a LiveCD is very limited. It may therefore be necessary to temporarily edit the sources.list file in the edit file system to add sources for desired packages. This can be done before and after the chroot. It is important to remove any temporary package sources after the chroot has been done. Edit the sources file like this:
sudo gedit edit/etc/apt/sources.list
DebConf
A number of important settings, such as default user groups, are stored in the debconf database. This can be queried and edited during a chroot.
To display default user groups:
echo "get passwd/user-default-groups" | debconf-communicate
To set default user groups:
echo "set passwd/user-default-groups adm cdrom dip lpadmin plugdev sambashare debian-tor lxd" | debconf-communicate
These groups are used for the creation of the LiveCD user on boot and are therefore available when running the LiveCD. Any other debconf key can be queried and edited as above.
Ending chroot and cleaning up
Before exiting chroot
Cleanup old kernel versions
Find a list of all currently installed kernel versions. An easy way to do this is to list the config files in the /boot folder:
ls -r /boot/config-*
This will provide a list. For each instance make a note of that version number. Then, list all linux packages:
dpkg --list | grep -i "linux-"
Then purge all the packages with old version numbers:
apt-get purge <packages>
For example:
apt-get purge linux-headers-5.15.0-43 linux-headers-5.15.0-43-generic linux-image-5.15.0-43-generic linux-modules-5.15.0-43-generic linux-modules-extra-5.15.0-43-generic
If you looked into the edit/boot folder before entering chroot and updating, you will have noticed that it contained a kernel file vmlinuz and an initrd / initramfs file called initrd.img. Both are symlinks pointing at numbered versions and both were, on your working machine, broken symlinks. Before updating, there were no actual kernel or initrd files there. After updating, there are.
When you have finished cleaning up all out of date kernels per the instructions above there should be one version of an actual kernel file, and one initrd file in the edit/boot folder. These will be moved and further worked on later in these instructions.
Cleanup apt and packages
Use the following commands.
apt-get autoremove apt clean apt-get clean
Cleanup temporary files
rm -rf /tmp/* ~/.bash_history rm /var/lib/dbus/machine-id rm /sbin/initctl dpkg-divert --rename --remove /sbin/initctl
Terminate / unmount in-chroot bindings and mounts
Unbind the in-chroot bindings set earlier:
umount /proc umount /sys umount /dev/pts
Exit chroot
exit
After exiting chroot
Remove further mounts and bindings set outside chroot
Execute the following commands:
sudo umount edit/run sudo umount edit/dev
Remove any temporary package sources from sources.list
Do not forget to remove temporary package sources:
sudo gedit edit/etc/apt/sources.list
Updating the kernel and initrd on the LiveCD proper
If you updated the kernel in the edit folder whilst in chroot you will need to update the kernel in the LiveCD proper. This will require recreation of the initrd file.
On the physical LiveCD file system, the Linux kernel is stored in the /casper subfolder. Casper is software that enables booting on diverse hardware by identifying appropriate drivers.
Copying the kernel
rm extracted/casper/vmlinuz cp edit/boot/vmlinuz extracted/casper/vmlinuz chmod 644 extracted/casper/vmlinuz
This should copy the kernel currently pointed at to the /casper folder on the LiveCD. Depending on the version of the cp command used an -L switch may be necessary to make it follow the symlink.
cp -L edit/boot/vmlinuz extracted/casper/vmlinuz
Extracting the current initrd file
Firstly, we need to extract the existing file to obtain required scripts using the unmkinitramfs command:
mkdir initrdmount unmkinitramfs -v extracted/casper/initrd initrdmount
Copying required files to a seed folder
The following commands extract the necessary files from the existing extracted initrd file tree to enable us to create a new one which will work with the LiveCD:
cp -R initrdmount/main/conf conf mv conf initrdconf cp -R initrdmount/main/scripts initrdconf/scripts
Creating a new initrd / initramfs file
With this done, the mkinitramfs command can be used to recreate the initrd file. This will draw materials from the host system, which is why the kernel versions must match precisely and why the casper, live-boot and live-boot-initramfs-tools must be installed in the host because they provide needed drivers:
mkinitramfs -d initrdconf -o ninitrd rm extracted/casper/initrd mv ninitrd extracted/casper/initrd
Clean up the squashfs /boot folder
As set out above, there are no linux kernel nor initrd / initramfs files in the edit/boot folder until you update. There are only broken symlinks. Now we have successfully put them in the /casper folder on the physical LiveCD file system we can once again break those symlinks:
rm edit/boot/initrd.img-* rm edit/boot/vmlinuz-*
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:
/usr/share/gnome-background-properties/ubuntu-wallpapers.xml and
/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:
gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.defaults --type string --set yourkey "yourvalue"
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
gconftool-2 --dump /the/settings/branch/you/need > ~/live/your-new-settings.xml sudo chown root:root ~/live/your-new-settings.xml sudo mv ~/live/your-new-settings.xml ~/live/edit/your-new-settings.xml
and then, in the chroot environment, run
gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.defaults --load /your-new-settings.xml rm /your-new-settings.xml
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
Legacy Boot
Change default language of gfxboot
This customization must be done outside the chroot.
sudo apt install dpkg-dev uck apt source gfxboot-theme-ubuntu gfxboot cd gfxboot-theme-ubuntu*/ make DEFAULT_LANG=fi sudo cp -af boot/* ../extract-cd/isolinux/
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/misc.py. If you look at the hard-coded defaults table at around line 620 it should be fairly obvious what's going on...
// In /usr/lib/ubiquity/ubiquity/misc.py line 620:
default_keymap = {
'ar': 'ara',
'bs': 'ba',
'de': 'de',
'el': 'gr',
'en': 'us',
etc...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:
dpkg-reconfigure keyboard-configuration
UEFI
UEFI booting uses GRUB instead of gfxboot. There's no options for changing the language or keyboard for the live session, so it's all English by default. Therefore GRUB configuration needs to be modified. In the Ubuntu Finnish Remix script this is done as follows:
sed -i '6i loadfont /boot/grub/fonts/unicode.pf2' boot/grub/grub.cfg sed -i '7i set locale_dir=$prefix/locale' boot/grub/grub.cfg sed -i '8i set lang=fi_FI' boot/grub/grub.cfg sed -i '9i insmod gettext' boot/grub/grub.cfg sed -i 's%splash%splash locale=fi_FI console-setup/layoutcode=fi%' boot/grub/grub.cfg sed -i 's/Try Ubuntu without installing/Kokeile Ubuntua asentamatta/' boot/grub/grub.cfg sed -i 's/Install Ubuntu/Asenna Ubuntu/' boot/grub/grub.cfg sed -i 's/OEM install (for manufacturers)/OEM-asennus (laitevalmistajille)/' boot/grub/grub.cfg sed -i 's/Check disc for defects/Tarkista asennusmedian eheys/' boot/grub/grub.cfg mkdir -p boot/grub/locale/ mkdir -p boot/grub/fonts/ cp -a /boot/grub/locale/fi.mo boot/grub/locale/ cp -a /boot/grub/fonts/unicode.pf2 boot/grub/fonts/
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:
awk -F: '$3 == 999' /etc/passwd
If you get any hits, try changing the uid:
usermod -u 500 $hit
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:
dpkg-reconfigure tzdata
If you have added a locale and wish to make it the default, update /etc/default/locale. You may have to compile the locale:
locale-gen new_locale update-locale LANG=new_locale LANGUAGE=new_locale LC_ALL=new_locale
These changes must be made as root in the chroot environment.
Advanced Customizations
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:
# cd extract-cd/casper # mkdir tempdir # cd tempdir # gunzip -dc ../initrd.gz | cpio -imvd --no-absolute-filenames # cp scripts/casper-bottom/25configure_init scripts/casper-bottom/25configure_init.orig # vi scripts/casper-bottom/25configure_init
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 $USERNAME string to see if it's length is non-zero. By removing the variable, and leaving two double quotes, this statement evaluates to false because the two double quotes effectively make a zero-byte string. Be sure to leave no whitespace between the quotes because whitespace will make the evaluation true and execution wil fall into the if block.
21:log_begin_msg "$DESCRIPTION" 22: 23:# Arrange for shells on virtual consoles, rather than login prompts 24: 25:if [ -n "$USERNAME" ]; then
After making the change, line 25 will look like this:
25:if [ -n "" ]; then
Save the file and quit the editor. Then, from extract-cd/casper/tempdir run the following command to re-create the initrd.gz file. There are other methods for re-creating the initrd.gz file on this page which may work also.:
# cp ../initrd.gz ../initrd.gz.orig # find . | cpio -o -H newc | gzip -9 > ../initrd.gz
This will create a new initrd.gz file with no auto login. You can then continue to remaster the CD as described on this page. Be sure to create a user and password to login with before you remaster the cd. If you do not, you will not be able to login after booting!
Also, I have read a few articles mentioning that Karmic (9.10) uses initrd.lz instead of initrd.gz. I do not know if this is true, but should mention it in case you are not getting the expected results. To unpack the initrd.lz file, you need to do this:
# cd extract-cd/casper # mkdir lztempdir # cd lztempdir # lzma -dc -S .lz ../initrd.lz | cpio -imvd --no-absolute-filenames
And to re-create the initrd.lz file:
# cp ../initrd.lz ../inird.lz.orig # find . | cpio --quiet --dereference -o -H newc | lzma -7 > ../initrd.lz
Boot init
You have to edit the files in edit/usr/share/initramfs-tools/scripts/casper-bottom/* For example you can change the hostname or the livecd user.
i.e.
sudo nano edit/usr/share/initramfs-tools/scripts/casper
and edit the username or hostname
sudo nano edit/usr/share/initramfs-tools/scripts/casper-bottom/10adduser
to edit even the livecd user's password.
If you're customizing 10.04, you need to edit variables in /etc/casper.conf for the user and host names instead of modifying the scripts
P.S. in order to obtain an encrypted password, you have to use the mkpasswd program that's shipped with whois package!
Producing the CD image
Assembling the file system
Regenerate manifest
chmod +w extract-cd/casper/filesystem.manifest
sudo su
chroot edit dpkg-query -W --showformat='${Package} ${Version}\n' > extract-cd/casper/filesystem.manifest
exit
sudo cp extract-cd/casper/filesystem.manifest extract-cd/casper/filesystem.manifest-desktop
sudo sed -i '/ubiquity/d' extract-cd/casper/filesystem.manifest-desktop
sudo sed -i '/casper/d' extract-cd/casper/filesystem.manifest-desktopCompress filesystem
sudo rm extract-cd/casper/filesystem.squashfs sudo mksquashfs edit extract-cd/casper/filesystem.squashfs -nolzma
- 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:
sudo mksquashfs edit extract-cd/casper/filesystem.squashfs -b 1048576
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:
sudo mksquashfs edit extract-cd/casper/filesystem.squashfs -comp xz -ef edit/boot
Update the filesystem.size file, which is needed by the installer:
sudo su printf $(du -sx --block-size=1 edit | cut -f1) > extract-cd/casper/filesystem.size exit
Set an image name in extract-cd/README.diskdefines
sudo vim extract-cd/README.diskdefines
(you can use "sudo nano extract-cd/README.diskdefines" if you have difficulties understanding vim)
Remove old md5sum.txt and calculate new md5 sums
cd extract-cd sudo rm md5sum.txt find -type f -print0 | sudo xargs -0 md5sum | grep -v isolinux/boot.cat | sudo tee md5sum.txt
Create the ISO image
sudo mkisofs -D -r -V "$IMAGE_NAME" -cache-inodes -J -l -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -o ../ubuntu-9.04.1-desktop-i386-custom.iso .
Or alternatively, if wanting to create an iso with options similar to the original iso, xorriso can be used to figure out options used to create the original iso. This, for instance, allows for easily creating images which will boot via bios and uefi as a cdrom and a harddisk image written to a usb flash.
# Add initial options first
cat <<EOF >xorriso.conf
-as mkisofs \\
-r -J --joliet-long \\
-o ubuntu-18.04-desktop-amd64-custom.iso \\
EOF
# Use xorriso do the magic of figuring out options used to create original iso, making sure
# to append backslash to each line as required.
xorriso -report_about warning -indev "ubuntu-18.04-desktop-amd64.iso" -report_system_area as_mkisofs |
sed -e 's|$| \\|'>>xorriso.conf
# Tell xorriso the root directory for the iso being created
echo 'extract-cd' >>xorriso.conf
# Modify options in xorriso.conf as desired or use as-is
sudo xorriso -options_from_file xorriso.conf
Testing the CD
Test BIOS boot using qemu emulator
qemu-system-i386 -cdrom ubuntu-9.04.1-desktop-i386-custom.iso -boot d -m 512
Or if you have hardware acceleration for kvm
kvm -cdrom ubuntu-9.04.1-desktop-i386-custom.iso -boot d -m 512
To test UEFI boot
qemu-system-x86_64 -bios OVMF.fd -cdrom ubuntu-18.04-desktop-amd64-custom.iso -boot d -m 512
To test hard drive boot use
qemu-system-x86_64 -hda ubuntu-18.04-desktop-amd64-custom.iso -boot d -m 512
You can also test with virtualbox-ose, which is free software and available in the Ubuntu universe repository.
Troubleshooting
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
cdrecord dev=/dev/cdrom ubuntu-9.04-desktop-i386-custom.iso
Additional uses for the image
Install Ubuntu from a USB stick
Installation From Image Loaded On Hard Drive
Comments
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) http://flamerobin.blogspot.com/2008/08/creating-flamerobinfirebird-livecd-with.html
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 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.
--Bob/Paul
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) http://flamerobin.blogspot.com/2006/05/creating-flamerobinfirebird-live-cd.html I created an updated guide with Ubuntu Festy Fawn also with an iso download for the Firebird/Flamerobin live cd http://flamerobin.blogspot.com/2007/09/creating-flamerobinfirebird-livecd-with.html
I have created tool for automatic remastering of live CD images. See http://uck.sourceforge.net/ .
Features:
- 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.
http://www.atworkonline.it/~bibe/ubuntu/custom-livecd.htm 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: http://lichota.net/%7Ekrzysiek/projects/kubuntu/dapper-livecd-optimization/
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.
cp /etc/X11/xorg.conf edit/etc/X11/
2. Create generic devices on your chroot system using MAKEDEV
cd /dev/ MAKEDEV generic
3. Start X or restart gdm
/etc/init.d/gdm start
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.
export HOME=/etc/skel/
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.
/etc/init.d/dbus start
An example of the whole procedure. (under single-user mode)
sudo /etc/init.d/networking restart sudo nano /run/resolvconf/resolv.conf # See notes about resolv.conf earlier this page. Add temporarily eg. nameserver 8.8.8.8, but do not touch /etc/resolv.conf in any way sudo cp /etc/X11/xorg.conf edit/etc/X11/ sudo chroot edit mount -o none /proc mount -o none /sys export HOME=/etc/skel/ cd /dev/ MAKEDEV generic /etc/init.d/dbus start /etc/init.d/gdm start
--- joelbryan
Hello,
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 ?
Thanks
Changing username and password will not change login behaviour, because this is done in /usr/share/initramfs-tools/scripts/casper-bottom/15autologin
Having trouble starting a MySQL server from within the chroot jail. Any suggestions?
- Dave
Hey,
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:
# diff ~/bin/dexconf /usr/bin/dexconf 268,269c268 < Option "XkbLayout" "us,il" < Option "XkbOptions" "grp:alt_shift_toggle,grp_led:scroll" --- > Option "XkbLayout" "$XKB_LAYOUT"
-- 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.
CD="${1:-kubuntu-9.04-desktop-i386.iso}" ; shift
# exit after any error:
set -e
which mkisofs mksquashfs tempfile sed
WDIR=`mktemp -d $PWD/kubuntu-remastered.XXXXXXXXXX`
ISO="$WDIR/${CD##*/}"
ISO="${ISO%.iso}-remastered-KDM.iso"
EXIT=""
function addExit {
EXIT="$@ ; $EXIT"
trap "$EXIT" EXIT HUP TERM INT QUIT
}
function mnt {
local margs="$1" ; shift
local mp="$WDIR/$1"
for D in "$@" ; do
mkdir -v -p "$WDIR/$D"
done
mount -v $margs "$mp"
addExit "umount -v $mp"
}
# mount the CD image
mnt "-t auto $CD -o loop,ro" cd
# mount compressed filesystem
mnt "-t squashfs $WDIR/cd/casper/filesystem.squashfs -o ro,loop" sq
# create joined writable filesystem for the new CD
mnt "-t aufs -o br:$WDIR/cd-w=rw:$WDIR/cd=ro none" cd-u cd-w
# create joined writable filesystem for the new compressed squashfs filesystem
mnt "-t aufs -o br:$WDIR/sq-w=rw:$WDIR/sq=ro none" sq-u sq-w
echo ">>> Updating CD content"
(
cd sq-u
# DO YOUR CUSTOMIZATION STUFF HERE, CHROOT, MODIFY FILES, ETC.
# ...
# ...
)
echo ">>> Compressing filesystem"
mksquashfs $WDIR/sq-u/ $WDIR/cd-u/casper/filesystem.squashfs -noappend
echo ">>> Recomputing MD5 sums"
( cd $WDIR/cd-u && find . -type f -not -name md5sum.txt -not -path '*/isolinux/*' -print0 | xargs -0 -- md5sum > md5sum.txt )
echo ">>> Creating ISO image $ISO"
mkisofs \
-V "Custom KUbuntu Live CD" \
-r -cache-inodes -J -l \
-b isolinux/isolinux.bin \
-c isolinux/boot.cat \
-no-emul-boot -boot-load-size 4 -boot-info-table \
-o "$ISO" \
$WDIR/cd-u
# The trap ... callbacks will unmount everything.--- Petr Pudlak
Petr - this looks interesting. How do you use it? When I run it, I get ./fix-live-cd.sh: 1: shift: can't shift that many. -- Jeff
I need to know how to configure the live cd so that it does not use SWAP!
Please help me!
-- iceman
Hi, I've been experiencing problems with aptitude and I'm pretty sure its because I'm doing all this stuff on NTFS partition (according to this thread http://ubuntuforums.org/showthread.php?t=521905). But I have no other choice,coz' I've got less then 1,7GB on my ext3 partition. Any suggestion ? THX
Error messages I've been getting, when trying to install or update aptitude:
"E: Couldn't make mmap of 25165824 bytes - mmap (19 No such device) W: Unable to munmap E: The package lists or status file could not be parsed or opened."
-heethen (heethen at centrum dot cz)
I would suggest creating an ext3 filesystem within your NTFS partition. To create the file, type
dd if=/dev/zero of=/mnt/hda1/workspace.img bs=1024 count=$((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
gconftool-2 --dump /the/settings/branch/you/need > ~/live/your-new-settings.xml sudo chown root:root ~/live/your-new-settings.xml sudo mv ~/live/your-new-settings.xml ~/live/edit/your-new-settings.xml
and then, in the chroot environment, run
gconftool-2 --direct --config-source xml:readwrite:/etc/gconf/gconf.xml.defaults --load /your-new-settings.xml rm /your-new-settings.xml
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:
ip=IFACE,ADDRESS,NETMASK,GATEWAY[:IFACE,ADDRESS,NETMASK,GATEWAY]*
--silid
http://ubuntuforums.org/showthread.php?t=839670
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.
auto eth0 iface eth0 inet static address 10.xxx.xxx.xxx netmask 255.255.255.0 gateway 10.xxx.xxx.1
edit somepath/isolinux/text.cfg add ip=frommedia after splash
label live menu label ^Try Ubuntu without any change to your computer kernel /casper/vmlinuz append file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.gz quiet splash ip=frommedia --
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: http://ubuntuforums.org/showthread.php?p=7334890#post7334890 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: http://david.decotigny.fr/wiki/wakka.php?wiki=RemasterUbuntu . 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,
printf "\nADD_EXTRA_GROUPS=1\nEXTRA_GROUPS="video"\n" >> /etc/adduser.conf
-- CarlKarsten
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:
root@maxwell:/home/Z_Custom# unsquashfs mnt/casper/filesystem.squashfs Filesystem on mnt/casper/filesystem.squashfs is (4:0), which is a later filesystem version than I support!
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?
Sincerely,
--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
asw_te
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 autoremove removes the old headers, but I have to purge the old kernel manually (apt 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:
LIVE_MEDIA_PATH=casper $path/.disk/casper-uuid append file=/cdrom/preseed/kubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --
becomes
LIVE_MEDIA_PATH=kubuntu/casper $path/kubuntu/.disk/casper-uuid append file=/cdrom/kubuntu/preseed/kubuntu.seed boot=casper initrd=/kubuntu/casper/initrd.lz quiet splash --
But the prefixed distributions show only an Install Ubuntu 9.10 link on the desktop, not Kubuntu (Xubuntu, LUbuntu, ...).
Thanks, René Leonhardt
Hi!
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
sudo cp edit/boot/vmlinuz-2.6.31-16-generic extract-cd/casper/vmlinuz sudo cp edit/boot/initrd.img-2.6.31-16-generic extract-cd/casper/initrd.gz
Since Karmic uses initrd.lz, I had to uncompress the .gz file and put it back in .lz format.
cd extract-cd/casper sudo mv initrd.lz inird.lz.orig gzip -dc initrd.gz | sudo lzma -7 > initrd.lz cd ~/live
To conserve space, you can remove the original initrd files before changing the directory back
sudo rm -f inird.lz.orig initrd.gz
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
ashlessburn
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.
Thanks
--Steve
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:
label live-install menu label ^Install Ubuntu kernel /casper/vmlinuz append file=/cdro...
-- 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...
Alejandro
I customize the live cd and install apache2 , webmin ,,, but how to make it start after the automatic-login ?
Gordon
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?
RJ
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.
exhuma
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 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!
SantanaNL
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.
bananax182
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:
deb http://archive.ubuntu.com/ubuntu natty universe deb-src http://archive.ubuntu.com/ubuntu natty universe
Then just updated apt and installed as normal:
apt update apt install dcfldd
Sorry if everyone already knew this. I just figured it may be helpful to users like myself.
mrgrant
Hi 
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
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.
Chad
I am a total beginner. How do I take my current computer configuration and turn it into a install CD? Thanks!
Nick (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
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.
Mike
"Unable to find a medium containing a live file system" when have customized LiveCD image.
I conveniently missed this step from the main document "Recognition as an Ubuntu Remix": https://help.ubuntu.com/community/LiveCDCustomizationFromScratch#Recognition_as_an_Ubuntu_Remix
As scripts/casper-bottom/41apt_cdrom script from initram image looks for ".disk/info" to recognize the Ubuntu image. If this file does not exist or is zero size on the DVD image, initramfs tools will not mount the CDROM/USB.
if [ ! -s /root/cdrom/.disk/info ]; then
- exit 0
fi
-Sunil