To build debian-live with unionmount you will need

• A linux kernel with unionmount support

  • Get a kernel from Valerie Aurora's git repo. This is a work in progress but using this kernel you should be able to boot Debian Live. You can check the repo for more up-to-date branches.
  • Configure and build the kernel. A suggested configuration file for i686 based on stock Debian configuration. Setting or unsetting some configuration options may not work yet.

  make-kpkg --rootcmd fakeroot --initrd --append-to-version -um-i686 kernel-image kernel-headers

• Unfortunately kernel-package and initramfs-tools package maintainers can't agree on a way to tell initramfs-tools to generate an initramfs so you will need to generate one in a hook (put in chroot_local-hooks). Also cross-building i686 on amd64 seems broken.

• Mount command with unionmount support

  • here is a patch which you can apply to Squeeze util-linux and rebuild. It may break some other options, I am not sure how those defines are supposed to work. You only need the mount package.
• Put your mount command into your initramfs
  • using a hook (put in chroot_local-hooks). With recent live-boot-initramfs-tools you should see unionmount among the included options printed during update-initramfs.
• Tell live-initramfs to use unionmount instead of aufs
  • Use some arguments like these with lb config

  -k um-i686+ \

  --bootappend-live union=unionmount \

  --packages "httpfs2 less open-iscsi links2" \

  --linux-packages linux-image-2.6.36-rc5 \