UPDATE: My development MBL which died is back alive

During kernel 5.4 Asynchronuous DMA driver work, my MBL died over 18 months ago. Apperently u-boot and/or u-boot variables were corrupted. In a nothing-to-lose-effort, I managed to unsolder a chip and reflash it.

My-Book-Live (MBL) customization

Kernel patches and Debian release for Western Digital My Book Live. NOTE: these customizations will void your warranty and are delivered on best-effort only NOTE: while the posted methods allow you to fully customize a MBL without ever opening it, you need to keep in mind that there might be a failure which requires you to ultimately open up the shell. NOTE: none of this work is tested on a My Book Live DUO for the simple reason that we don't own one. That said it, community members have successfully deployed on MBL Duo.

Why customize ?

My disk died: in this scenario, you may have to open up your MBL if your warranty is void and you will be exposed to the "complexity" of Linux commands/shell scripts, formatting, u-boot, etc. It's a good time to explore all the possibilities.
Supportability: original firmware comes with Debian Lenny (5.0.x), which was released in February 2009. Security and other updates have been discontinued as of February 2012. While Western Digital has done a great job to provide updated firmware, it's ultimately impossible to keep up with back-porting vulnerability updates on pre-2010, outdated releases.
Security vulnerabilities: protect your valuable data (see report)
Performance: custom kernels can increase your performance by 50%+
Functionality: many new packages are no longer supported on 2.6 kernels and Debian Jessie (e.g. newer versions of Samba with better Windows 10 support)

Why not customize ?

Losing WD support/warranty
Loss of the graphical user interface: while it's possible to port the original web user interface, it's not really worth it the time and effort.

Tree Structure

debian: Debian 8.11 with security patches backported to PowerPC
kernel: Kernel patches, pre-compiled kernels and device tree structure
samba : Optimal perfomance with Samba using sample config files
uboot : Netconsole support, u-boot boot files, TFTP boot and ways to safely boot My Book Live

Documentation is posted within each section.

Latest validated kernel support

Kernel 2.6.32.71, released Sat, 12 Mar 2016
Kernel 4.9.169, released Wed, 17 Apr 2019
Kernel 4.19.99, released Mon, 27 Jan 2020

What is new ?

4.19 kernel (pre-compiled and patches) released
high performance kernel 4.19.99 released
patches updated for 4.19.99
section on Samba
section on cross-compiling kernels
fixed a few Github postng issues
released 4.9.149 & 4.9.169
support for TFTP booting including netconsole support
initramfs section
improved section on installing custom kernels on original firmware
update on Debian sources.list (package repositories)

Known issues

(Disk activity) led not working on 4.19 kernels