OpenWRT automatic installer

Article was updated on 2023-11-25

This is an automatic OpenWRT installer for APU2/3/4/6 routers. This method doesn't require a serial cable. 

This process will install a new OpenWRT on the router and flash the latest BIOS version. This tutorial is intended for two types of situation:

  1. Something happened with your router, and you want to recover quickly.
  2. You don't have a serial cable or don't want to go through the manual installation process for OpenWRT.

The current version of the auto-installer has been prepared on November 25, 2023, and is preloaded with:

  • BIOS v4.19.0.1 (Release date: 2023-02-02)
  • OpenWRT 23.05.2 (Release date: 2023-11-15)


  1. You have an APU2, APU3, APU4 or APU6 router.
  2. You have at least a 16GB SSD in the router
  3. You will need a USB stick with at least 2GB. Larger sticks are OK.

Here are the instructions

  1. Download the USB image from here:
  2. Flash the ISO image on a USB stick with Rufus on Windows or dd on Linux/macOS.
  3. Insert the USB drive into the router and insert the power cable
  4. The router will boot from the USB, it will flash a new BIOS and automatically install a new OpenWRT on the SSD.
  5. APU will make some beep sounds during the installation process. In the end, there will be 3 beeps with 1s pause in between and the router will pwoer off. The entire process should take about 2-3 minutes.
  6. After you hear the 3 beeps, your router should power off automatically, remove the USB stick, remove the power plug and put it back in to power on the device. Don't power off the router while the autoinstaller is working.
  7. It should boot with OpenWRT and new BIOS.

Default configuration

  • Port 1: WAN (closest to the serial port)
  • Port 2: LAN
  • LAN address:
  • username: root
  • password: blank (please change)
  • WiFi: not configured

All drivers recommended in the manual installation process for OpenWRT have been installed.

Steps to perform after installation

After the automatic installed did its job, you will want to adjust some configuration settings to suit your network.

Connect a network cable between your computer and a LAN port on APU. You should get an address from the router and be able to connect to - you may need to use an incognito window in your browser.

Set the administrator password on the router

By default, the username is "root" and thepassword is blank. Make sure to set a secure password to protect the router from unauthorized changes.

Activate extra LAN ports

The auto-installer sets the first port as WAN and the second port as LAN. If your router has 3 or 4 ports, the remaining ports are likely not active. You will have to enable the remaining ports. You will likely want them to be on the LAN network. To assign these ports to LAN, follow these steps:

Go to Network -> Interfaces -> LAN -> Edit -> Physical Settings -> Pick eth1, eth2 and eth3 in "Interfaces" and Save.

Activate WiFi adapters

If you have WiFi adapters in your router, you will need to configure and enable them. All the drivers and software are installed already, but the wireless networks are not configured and activated.

Go to Network -> Wireless -> Edit 

If you need detailed instructions, see OpenWRT WiFi configuration instructions


The USB stick does not boot / router doesn't make any sounds

Try a different USB stick. APU doesn't like certain USB3 sticks. Try USB2 stick if you have one.

By default APU boots first from the USB stick and then from SSD. If you have reconfigured this behaviour in BIOS you will have to change it back. There are two ways: serial cable connection or the CLEAR CMOS jumper on the motherboard.

When I connect to the LAN port, I can't access the web interface

Try using the incognito window. Make sure the link starts with HTTPS, like here: