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You have a little router’ dated that he takes dust? I have a Fritz!Box 4020 which in point in white stopped working. It was integrated with the router and I already used it as a Wi-Fi Extender on the upper floor. Apparently there is no procedure to carry out a factory reset and before slinging on eBay I would like to explore all the options. The fact remains that the Wi-Fi coverage of the house should expand in an efficient and controlled way, But first I have to somehow “unlock” l’access point. Excellent news: We can reuse it by transforming it into a Access Point (AP) Wi-Fi with OpenWrt.

You don't have a Fritz!Box 4020? However, try checking on the OpenWRT website in the section relating to’Supported hardware. Most likely your device will be present.

OpenWRT is a light and flexible operating system based on Linux, Specifically designed for router and embedded devices. It allows us to bypass the limitations of the original firmware and to have total control over our network device. In this guide, We will see how to install it and configure the Fritz!Box 4020 To make it work as an intelligent access point, managing wi-fi and traffic on the LAN doors, All by disabling the DHCP and setting a fixed IP in your existing network.

To start: What do you need

Before starting, Make sure you have at hand:

1. Fritz!Box 4020: The router we will transform.
2. Ethernet cable: To connect the PC to the Fritz!Box.
3. PC con porta ethernet: For the initial configuration.
4. Working internet connection: To download the openwrt firmware.
5. Firmware OpenWrt per Fritz!Box 4020: You will download it from the official OpenWRT website. Make sure you take the specific version for your model, it is usually a file .bin.
6. A dust’ patience!

Phase 1: installare OpenWrt sul Fritz!Box 4020

OpenWRT installation on a Fritz!Box requires a particular step, since you cannot install the standard web interface directly. A small trick is used that uses a method of recovering the router.

Keep in mind that the procedure is totally reversible (AVM firmware can be restored) and the instructions, very detailed, are indicated On the OpenWRT website.

General steps:

1. Download the firmware OpenWrt corretto: Visit the official website and download the openwrt firmware.
2. Set the IP of your PC a 192.168.178.10 con subnet mask 255.255.255.0. This is necessary because the FRITZ!Box in recovery mode will use a fixed IP in that class.
3. Connect the PC to the Fritz!Box through one of the LAN doors of the Fritz!Box with the Ethernet cable. Don't connect the Fritz!Box to your main router at this stage and don't connect via Wi-Fi.
4. Disable Wi-Fi on the computer you are using for configuration of the device.
5. Turn on the Fritz!Box in special mode:
   • Disconnect the diet from the Fritz!Box and wait 30 seconds.
   • Connect the power supply again and, within the first 5 seconds, launches the command ftp -n -4 192.168.178.1.
6. Upload the firmware:
   • Launch these commands once you have access to the FTP prompt:
   • ftp> quote USER adam2
   • ftp> quote PASS adam2
   • ftp> binary
   • ftp> debug
   • ftp> passive
   • ftp> quote MEDIA FLSH
   • ftp> put openwrt-sysupgrade.bin mtd1 (Here you will have to specify the file just downloaded)
   • ftp> close
   • ftp> quit
7. Install the final version of OpenWRT: Restart the router by disconnecting it from food. Now the new firmware will be installed and you can access the OpenWRT web interface (Call lights) at the address http://192.168.1.1. So you need to change the IP of the PC with on you are working in this sense.

Important note: Specific instructions for the initial installation of the openwrt firmware on the Fritz!Box can be very detailed and depend on the exact model and on the OpenWRT version. It is essential to consult the official OpenWRT documentation for the Fritz!Box 4020 (Check the previous link) before proceeding, Since an error at this stage could block the router.

Phase 2: Configurare OpenWrt come access point

Now that OpenWrt is installed, We can configure it for our purpose.

Network scenario:

• IP class: 192.168.5.x
• Gateway (Main routing): 192.168.5.1
• IP dell’Access Point (Fritz!Box 4020): 192.168.5.50
• DHCP: Disabled on the Fritz!Box (managed by the main router).

Configuration steps:

1. Connect to the Fritz!Box con OpenWrt:
   • Connect your PC directly to the Fritz!Box (any LAN gate).
   • Make sure the IP of your PC is in the same class as the Fritz!Box (di default 192.168.1.x For OpenWRT just installed) or receiving an IP via DHCP from the Fritz!Box itself (which is active by default on OpenWRT).
   • Open the browser and go to http://192.168.1.1 (This is the predefined Imps of OpenWRT just installed).
   • You will be asked to set up a password for the user “root”. Do it immediately!
2. Set up the lan interface:
   • Once logged, children with Network -> Interfaces.
   • Search for the interface LAN and click on Edit.
   • In the section General Setup:
     • Change the Protocol the Static address a Static address (if it is not already).
     • Tax IPv4 address its 192.168.5.50.
     • Tax IPv4 netmask its 255.255.255.0.
     • Tax IPv4 gateway its 192.168.5.1 (The IP of your main router).
     • If you have set the router DNS you can set the DNS servers its 192.168.5.1, or you can set the external ones (this is. those of Google: 8.8.8.8).
   • Do not touch the section DHCP Server for now, We will disable it at the next point.
   • I don't click on Save and then Save & Apply.
   • Caution: After clicking Save & Apply, You will lose the connection with the Fritz!Box because his IP will be changed.
3. Disable the DHCP server on the Fritz!Box:
   • Now, Connect the Fritz!Box 4020 with an ethernet cable to one of its LAN doors to your main router. Do not use the WAN/DSL port if present; We want all LAN doors and Wi-Fi to be on the same network as the main router.
   • Reconfigure the IP address of your PC to return to “Automatically get an IP address” (DHCP), so that it receives an IP from your main router in the class 192.168.5.x.
   • Once your PC has a valid IP (this is. 192.168.5.x), open the browser and go to http://192.168.5.50 (The new IP of your Fritz!Box). Log in with the password you have set.
   • Go again on Network -> Interfaces -> Edit on the interface LAN.
   • Go to the card DHCP Server.
   • Check the box “Disable DHCP for this interface”.
   • I don't click on Save and then Save & Apply.
4. Configure the wireless network (Wi-Fi):
   • Go up Network -> Wireless.
   • You will find one or more Wi-Fi interfaces (eg, radio0 for 2.4 GHz). I don't click on Edit Next to the interface you want to configure.
   • In the section Interface Configuration:
     • Mode: Insured is set to Access Point.
     • ESSID: Enter the name you want to give to your Wi-Fi network (this is. CasaMia_Estensione).
     • Network: Make sure it is associated with lan. This will ensure that Wi-Fi is on the same wired network.
   • Go to the card Wireless Security:
     • Encryption: Choose a safe option like WPA2-PSK.
     • Key: Enter the password for your Wi-Fi network.
   • I don't click on Save and then Save & Apply. The Fritz!Box 4020 It does not support nets at 5GHz, but if you were using a different device that supports them repeat the process.

Final checks

1. Connection of Wi-Fi devices: Try connecting a device (smartphone, tablet) to the new Wi-Fi network you created. It should get an IP address from your main router (192.168.5.x) and have access to the Internet.
2. LAN ports connection: Connect a PC or another device to one of the remaining LAN doors of the Fritz!Box. This device should also get an IP from the main router and have access to the Internet.
3. Access to the Fritz!Box: Check that you can always access the Fritz OpenWRT Web interface!Box at the address http://192.168.5.50.

Congratulations! You have transformed your Fritz!Box 4020 In a Wi-Fi access point perfectly integrated in your network. This offers you unprecedented control on your network device and allows you to extend Wi-Fi coverage efficiently and stablely.