First read about netconsole here: https://www.kernel.org/doc/Documentation/networking/netconsole.txt

The WD MBL netconsole implementation requires the following:
- netconsole enabled uboot files
- netconsole enabled kernel
- netconsole enabled Linux kernel patches and config file (if you want to compile your own kernel)

DO NOT TEST THIS WITHOUT ABILITY TO TAKE YOUR DRIVE OUT AND HOOK TO A LINUX SYSTEM


**** First we will test a prebuild kernel without modifying uboot boot file
To quickly test netconsole
1. Download and Unpack netconsole.tgz

cd /tmp
wget "https://drive.google.com/uc?export=download&id=0B8Nj6R0Fc58pQmhCd0V3NmU4YjQ" -O netconsole.tar.gz
tar xvfz netconsole.tgz

2. test if you have the mkimage command, if not install it using "apt install u-boot-tools"
mkimage -?
apt install u-boot-tools

3. install prebuild kernel 4.1.39
cd /tmp
wget "https://drive.google.com/uc?export=download&id=0B8Nj6R0Fc58pbnRPNnFUU1lqLWc" -O netconsole_kernel.tar.tz
cd /
tar xvzf netconsole_kernel.tar.tz
cd /boot
cp uImage uImage.orig
cp uImage_4.1.39-mbl.netconsole uImage

4. reboot (and hope for the best)
systemctl reboot (on Debian 8.7 jessie)
 
5. if the system comes up you have a netconsole enabled kernel which you can test
mkdir /sys/kernel/config/netconsole/linuxConsole
cd /sys/kernel/config/netconsole/linuxConsole
echo 0 > enabled                        # disable the target (if required)
echo eth0 > dev_name                    # set local interface
echo 192.168.1.18 > remote_ip           # update some parameter
echo bc:5f:f4:cb:2f:2c > remote_mac     # update more parameters
echo 1 > enabled                        # enable target again

"linuxConsole" is just a name for a given netconsole. Any name will do
substitute your remote ip address and mac address

6. on your linux server (there are solutions for Windows too) start the monitoring using netcat
nc -u -l -p 6666

7. now send a test message from the MBL, if all is well you will see on your Linox box
echo "test message" >/dev/kmsg

**** Now we will boot the kernel with NETCONSOLE enabled
8. modify the uboot boot file with your netconsole settings
cd /tmp/uboot
edit boot.netconsole.txt
modify to match your IP addresses to match my settings
	netconsole=6665@192.168.1.6/eth0,6666@192.168.1.18/bc:5f:f4:cb:2f:2c
	netconsole=[+][src-port]@[src-ip]/[<dev>],[tgt-port]@<tgt-ip>/[tgt-macaddr]
where
        +             if present, enable extended console support
        src-port      source for UDP packets (defaults to 6665)
        src-ip        source IP to use (interface address)
        dev           network interface (eth0)
        tgt-port      port for logging agent (6666)
        tgt-ip        IP address for logging agent
        tgt-macaddr   ethernet MAC address for logging agent (broadcast)

Note: my example uses EXT3 as root file system.  If yours is EXT2, please change

9. now we will enable the kernel to boot with netconsole enabled
cp /tmp/uboot/boot.scr.netconsole /boot

10. make a copy of your original uboot file, just in case....  Install the new uboot loader
cp /boot/boot.scr /boot/boot.scr.orig
cp /boot/boot.scr.netconsole /boot/boot.scr

11. reboot and watch the the whole log come through :-)

**** Optinally we will build our own 4.1.39 kernel (assume you have unpacked 4.1.39 source files and are in the root directory)


for i in $(ls /tmp/patches/[0-9]*)
do
  echo #### $i ####
  patch -p 1 -b -i $i
done
cp /tmp/patches/config_4.1.39_netconfig .config
make uImage
make modules_install