WARNING: If you need any clarification installing or configuring your ZyXEL WSM20, please ask here:

And not on this current topic which is meant exclusively for development purposes.

I've added the WIKI page also with all the information we will be finding in this thread:

Already available to download in the latest snapshots:

Installation from ZyXEL UI: zyxel_wsm20-initramfs-kernel.bin

Installation instructions:

  1. Log into the OEM web GUI
  2. Access the hidden upgrade page by navigating to
    http://<ROUTER_IP>/gui/#/main/debug/firmwareupgrade
  3. Upload the -initramfs-kernel.bin file and flash it
  4. Wait for OpenWrt to boot and log in via SSH
  5. Transfer the sysupgrade file via SCP (192.168.1.1 by OpenWrt default)
  6. Run sysupgrade to install the image
  7. Reboot and enjoy

Upgrade from OpenWrt: zyxel_wsm20-squashfs-sysupgrade.bin

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