UbuntuHelp:LiveCDCustomization
来自Ubuntu中文
目录
- 1 How to customize the Ubuntu Desktop CD
- 2 System Requirements
- 3 The Process
- 4 Comments
How to customize the Ubuntu Desktop CD
You may wish to customize the Ubuntu desktop (live) CD, possibly to show off a particular application, or localize to a certain language. Here's how.
This guide is for the Desktop/Live CD; there is another page referrring to customization of the Alternative Install or Server Install CD.
System Requirements
- About 3-5 gigabytes of free space
- Recommended at least 512 MB RAM and 1 GB swap
- `squashfs-tools`
- `mkisofs`
- An Ubuntu kernel with `squashfs` support (the stock kernel in DapperDrake has it)
- QEMU, VirtualBox or VMware for testing
The Process
First, make sure that you have installed the needed tools:
sudo apt-get install squashfs-tools mkisofs qemu
Load the squashfs module
sudo modprobe squashfs
You need to download an official Desktop CD from http://releases.ubuntu.com/.
Move or copy it into an empty directory:
mkdir ~/live mv ubuntu-6.06.1-desktop-i386.iso ~/live cd ~/live
Extracting the CD contents
Mount the Desktop .iso
mkdir mnt sudo mount -o loop ubuntu-6.06.1-desktop-i386.iso mnt
Extract .iso contents into dir 'extract-cd'
mkdir extract-cd rsync --exclude=/casper/filesystem.squashfs -a mnt/ extract-cd
Extracting the Desktop system
Mount the squashfs filesystem
mkdir squashfs sudo mount -t squashfs -o loop mnt/casper/filesystem.squashfs squashfs
Extract squashfs contents into dir 'edit'
mkdir edit sudo cp -a squashfs/* edit/
Warning: Do not use `unsquashfs` command from Ubuntu 6.10 (Edgy), because it doesn't honour set-id bits (https://launchpad.net/bugs/89417). The version in Ubuntu 7.04 (Feisty) is fine.
Prepare and chroot
If you need the network connection within chroot:
sudo cp /etc/resolv.conf edit/etc/
Depending on your configuration, you may also need to copy the hosts file:
sudo cp /etc/hosts edit/etc/
sudo chroot edit mount -t proc none /proc mount -t sysfs none /sys
To avoid locale issues and in order to import GPG keys, set:
export HOME=/root export LC_ALL=C
Customizations
Few example customizations, and tips
Apt-get
To view installed packages by size:
dpkg-query -W --showformat='${Installed-Size} ${Package}\n' | sort -nr | less
When you want to remove packages remember to use purge
apt-get remove --purge package name
Custom Background for GNOME
Generally background files are located in /usr/share/backgrounds. Copy your png file there and edit the files:
- /usr/share/gnome-background-properties/ubuntu-wallpapers.xml and
- /etc/gconf/gconf.xml.defaults/%gconf-tree.xml
by changing the string /usr/share/backgrounds/warty-final-ubuntu.png to point to your file. More...
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...
Change default language of gfxboot
This customization must be done outside the chroot.
sudo -s apt-get install dpkg-dev apt-get source gfxboot-theme-ubuntu gfxboot cd gfxboot-theme-ubuntu*/ make DEFAULT_LANG=fi sudo cp -af boot/* ../extract-cd/isolinux/ exit
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.
Customization limits
After customization make sure that there are no users with an UID >= 1000. Otherwise your image won't boot because no initial user is available (see /usr/lib/user-setup/functions.sh and /usr/lib/user-setup/user-setup-apply). While in chroot:
grep '<sup>[^:]*:[</sup>:]*:[1-9][0-9][0-9][0-9]:' /etc/passwd grep '<sup>[^:]*:[</sup>:]*:[12][0-9][0-9][0-9][0-9]:' /etc/passwd
If you get any hits, try changing the uid:
usermod -u 500 $hit
Advanced Customizations
Live CD Kernel
If you want to customize further the boot process, you can change the livecd kernel, by copying the vmlinuz and initrd you want in place of the ones you find in extract-cd/casper (don't forget to apt-get the right kernel, the one that matches the livecd one, once chrooted into edit).
i.e.
sudo cp /boot/vmlinuz-2.6.15-26-k7 extract-cd/casper/vmlinuz sudo cp /boot/initrd.img-2.6.15-26-k7 extract-cd/casper/initrd.gz
Boot init
You have to edit the files in edit/usr/share/initramfs-tools/scripts/casper-bottom/* For example you can change the hostname or the livecd user.
i.e.
sudo nano edit/usr/share/initramfs-tools/scripts/casper
and edit the username or hostname
sudo nano edit/usr/share/initramfs-tools/scripts/casper-bottom/10adduser
to edit even the livecd user's password.
P.S. in order to obtain an encrypted password, you have to use the mkpasswd program that's shipped with whois package!
Rebuilding initrd
After you've modified the kernel, init scripts or added new kernel modules, you need to rebuild the initrd.gz file and substitute it into the casper directory.
sudo chroot edit mkinitramfs -o /initrd.gz 2.6.15-26-k7
(replace the kernel version with the one that the CD will boot with - this can be found in edit/lib/modules)
Exit from the chroot jail and move this file to extract-cd/casper:
exit mv edit/initrd.gz extract-cd/casper/
Cleanup
Be sure to remove any temporary files which are no longer needed, as space on a CD is limited. A classic example is downloaded package files, which can be cleaned out using:
apt-get clean
Or delete temporary files
rm -rf /tmp/*
Or nameserver settings
rm /etc/resolv.conf
now umount (unmount) special filesystems and exit chroot
umount /proc umount /sys exit
Putting the CD together
Regenarate manifest
chmod +w extract-cd/casper/filesystem.manifest
sudo chroot edit dpkg-query -W --showformat='${Package} ${Version}\n' > extract-cd/casper/filesystem.manifest
sudo cp extract-cd/casper/filesystem.manifest extract-cd/casper/filesystem.manifest-desktop
sudo sed -ie '/ubiquity/d' extract-cd/casper/filesystem.manifest-desktop
Compress filesystem
sudo rm extract-cd/casper/filesystem.squashfs sudo mksquashfs edit extract-cd/casper/filesystem.squashfs
Set an image name in extract-cd/README.diskdefines
sudo vim extract-cd/README.diskdefines
Remove old md5sum.txt and calculate new md5 sums
sudo -s rm extract-cd/md5sum.txt (cd extract-cd && find . -type f -print0 | xargs -0 md5sum > md5sum.txt) exit
Create Iso
cd extract-cd sudo mkisofs -r -V "$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-6.06.1-desktop-i386-custom.iso .
Testing the CD
Test using qemu emulator
qemu -cdrom ubuntu-6.06.1-desktop-i386-custom.iso -boot d
You can also test with vmplayer (which is free for Linux) which is a little faster than qemu, albeit not free and open source software.
Burning the image to CD
Simple! Just do:
cdrecord dev=/dev/cdrom ubuntu-6.06.1-desktop-i386-custom.iso
Comments
If you have any comments or questions, please feel free to add them here.
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 cp /etc/resolv.conf edit/etc/ 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
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
--- UbuntuHelp:Alexander Hosfeld
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
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
