Custom-built Ubuntu LiveDVD

$ export CUSTOM=~/custom-built
$ mkdir -p $CUSTOM

$ sudo mount -t iso9660 -o loop ubuntu-8.04.1-dvd-amd64.iso /mnt
$ cd $CUSTOM

$ mkdir custom-live
$ cp -a /mnt/. custom-live
$ chmod -R u+w custom-live
$ sudo umount /mnt

# 清理一些windows下的自由软件
$ rm -rf $CUSTOM/custom-live/programs

# 挂载前面复制的光盘文件，作为一个完整的linux os目录
$ mkdir $CUSTOM/reference
$ sudo mount -t squashfs -o loop,ro $CUSTOM/custom-live/casper/filesystem.squashfs $CUSTOM/reference

# 建立一个5GB左右的文件系统，然后把这个文件当作一个设备文件格式化。忽略系统警告。
$ sudo dd if=/dev/zero of=$CUSTOM/ubuntu-fs.ext3 bs=1M count=5120
$ sudo mke3fs $CUSTOM/ubuntu-fs.ext3

$ mkdir $CUSTOM/custom
$ sudo mount -o loop $CUSTOM/ubuntu-fs.ext3 $CUSTOM/custom
$ sudo cp -a $CUSTOM/reference/. $CUSTOM/custom
$ sudo umount $CUSTOM/reference

# 进入复制的linux
$ sudo cp /etc/resolv.conf $CUSTOM/custom/etc/
$ sudo mount -t proc -o bind /proc $CUSTOM/custom/proc
$ sudo chroot $CUSTOM/custom /bin/bash

# vi /etc/apt/sources.list
# apt-get update
# apt-get dist-upgrade
# apt-get install ...
# apt-get clean
# ...
# exit

# 返回系统初始状态
$ sudo umount $CUSTOM/custom/proc
$ sudo rm $CUSTOM/custom/etc/resolv.conf

# 修改manifest
$ sudo chroot $CUSTOM/custom dpkg-query -W --showformat='${Package} ${Version}\n' > $CUSTOM/custom-live/casper/filesystem.manifest

# “磁盘清理”
$ sudo dd if=/dev/zero of=$CUSTOM/custom/dummyfile
$ sudo rm $CUSTOM/custom/dummyfile

# 重新压缩系统
$ sudo rm $CUSTOM/custom-live/casper/filesystem.squashfs
$ cd $CUSTOM/custom
$ sudo mksquashfs . $CUSTOM/custom-live/casper/filesystem.squashfs

$ cd $CUSTOM
$ sudo umount $CUSTOM/custom

# 重新计算md5
$ cd $CUSTOM/custom-live
$ sudo find . -type f -print0 |xargs -0 md5sum |sudo tee md5sum.txt

# 建立光盘镜像
$ cd $CUSTOM
$ sudo mkisofs -o ubuntu-8.08-dvd-amd64.iso -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -r -V "Ubuntu 8.08 LiveDVD" -cache-inodes -J -l custom-live