Anycubic Kobra 2 Series Things

This repository contains things related to the Anycubic Kobra 2 Series 3D printer.

Discussion

Link (klipper.discourse.group)

Root

At the moment the only way to get root access is to use the serial console. The serial console is available on the 4 pin header on the mainboard.

Once basic serial communication is established, you can send the following commands to get root access:

1. Hold down the S key while powering on the printer.

2. Enter these commands to change bootargs:

setenv init /bin/sh
saveenv
bootd

Now you have a root shell.

Now you need to override the root password. To do this, you need to mount the overlay partition:

mount -t proc p /proc

. /lib/functions/preinit.sh

. /lib/preinit/80_mount_root

do_mount_root

. /etc/init.d/boot

link_by_name

. /lib/preinit/81_initramfs_config

do_initramfs_config

Then you can override the root password:

cp /etc/shadow /overlay/upper/etc/shadow

Just replace the password hash with something. You can use this website to generate a password hash.

After that is done, you need to reboot into U-Boot again and change the bootargs back to normal:

setenv init /sbin/init
setenv bootdelay 3
saveenv
reset

Now you can login with the password you set.

That's it! You now have root access.

For permanent ssh access, you can do the following:

Download and extract https://bitfab.org/dropbear-static-builds/dropbear-v2020.81-arm-none-linux-gnueabi-static.tgz 2 to somewhere.

Keep extracting until you can see the file called: dropbearmulti.

Then start a temporary HTTP server using python:

python -m http.server

Make sure to run the command in the same directory as the dropbearmulti file.

The URL should be something like: http://10.0.0.143:8000/dropbearmulti

Download the ssh script in the ssh folder in this repository.

Also place the script in the same folder as dropbearmulti: http://10.0.0.143:8000/installssh.sh

Make sure you change the IP to your computer.

Then run on the busybox on the printer:

wget http://10.0.0.143:8000/installssh.sh -O /tmp/
chmod +x /tmp/installssh.sh
/tmp/installssh.sh

That's it! You now have permanent ssh access.