Latest version built fails with "unmkinitramfs" mission

[melodie11]

Hello Kamilion, I built the version customizer_4.2.0-0+20180825_all.deb as per the instructions on the present wiki, installed the new depends (especially qt5 as python3 was already there).
A search on the web brought me to install initramfs-tools-core in which "unmkinitramfs" should have been but it was not.
Here is the output from the "customizer -r" command:

" customizer -r

• Read Configuration file: /etc/customizer.conf
• Rebuilding ISO...
  => Checking
  => Doing sanity checks
  => Gathering information
  => Cleaning up
  => Updating initramfs
  update-initramfs: Generating /boot/initrd.img-4.11.0-14-generic
  cryptsetup: WARNING: could not determine root device from /etc/fstab
  W: mdadm: /etc/mdadm/mdadm.conf defines no arrays.
  => Copying boot files
  => Extracting casper UUID
  /usr/sbin/chroot: failed to run command 'unmkinitramfs': No such file or directory
• SUBPROCESS: Command '/usr/sbin/chroot /home/customizer/FileSystem unmkinitramfs /boot/initrd.img-4.11.0-14-generic conf/' returned non-zero exit status 127
  "

oops, I found your binary! Next step might see me succeed?

[melodie11]

Hi Kamilion, I have been able to build a i386 version, but I can't get the x86_64 to work.
The build machine is a remote server running Ubuntu 16.04. (4.4.0-154-generic ... x86_64 x86_64 x86_64 GNU/Linux).

Here is the message:
"sudo customizer -r

• Read Configuration file: /etc/customizer.conf
• Rebuilding ISO...
  => Checking
  => Doing sanity checks
  => Gathering information
  => Cleaning up
  => Updating initramfs
  update-initramfs: Generating /boot/initrd.img-4.4.0-154-generic
  cryptsetup: WARNING: could not determine root device from /etc/fstab
  => Copying boot files
  => Extracting casper UUID
  /usr/sbin/chroot: failed to run command 'unmkinitramfs': No such file or directory
• SUBPROCESS: Command '/usr/sbin/chroot /home/customizer/FileSystem unmkinitramfs /boot/initrd.img-4.4.0-154-generic conf/' returned non-zero exit status 127
  "
  well, it is there!

$ which unmkinitramfs 
/usr/bin/unmkinitramfs

$ ls -l /usr/bin/unmkinitramfs
-rwxr-xr-x 1 root root 2859 Aug 26 2018 /usr/bin/unmkinitramfs

I have tried to rebuild the customizer deb, checked the /usr/bin/unmkinitramfs permissions, checked the files extracted from the ISO, don't know about kernels, just to be sure I have both host and extracted iso have the same kernel version. 

I have absolutely no clue about what to try next. How can I fix it?

[kamilion]

All of the newer kernel builds contain intel and AMD microcode to be applied as early as possible to defend against speculative execution attacks like Spectre.

Older images will not contain the unmkinitramfs script required to disassemble such an initramfs.

you need the unmkinitramfs script inside the chroot's /usr/bin/unmkinitramfs so you'll have to copy it inside the FileSystem folder yourself during your own build process.

[melodie11]

Hello Kamilion,
this has solved my issue, thanks a lot.

[melodie11]

Do you know if it's possible to rebuild let's say, a 18.04 from within a 16.04 without meeting with issues?