AVM Router Configuration

Configuration of an AVM router to reach a downstream OpenWRT device from your network:

– DynDNS
– Port Forwarding
– IPv4 settings
– IPv4 Routes

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Go to all articles of this series and the description of the test setup:

➡ OpenWRT – Overview

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• DNS Settings
• DynDNS
• Port Forward
• Network Settings
  • IPv4 settings
  • IPv4 Routes

The AVM device (= AVM FRITZ!Box 7390) is the router in the local network that establishes the internet connection to your ISP.

• AVM FRITZ!Box 7390 = router
• AVM FRTIZ!Box 4040 = OpenWRT

The OpenWRT (= AVM FRTIZ!Box 4040) is connected via WAN port to the AVM router.

DNS Settings

Use DNS server you trust. By default the router gets the DNS servers provided and maintained by your ISP.

List of DNS servers

• ➡ https://digitalcourage.de/support/zensurfreier-dns-server
• ➡ https://www.kuketz-blog.de/empfehlungsecke/#dns
• ➡ https://ffmuc.net/wiki/doku.php?id=knb:dns

ATTENTION!!!
No matter which DNS server you choose, support the provider. The server runs not only by air and love! Donations are very welcome!

ACHTUNG!!!
Egal für welchen DNS Server du dich entscheidest, unterstütze den Anbieter. Der Server läuft nicht nur von Luft und Liebe! Spenden sind immer willkommen!

DynDNS

The DynDNS configuration on the router is required to get a temporary public IP address.

Port Forward

In the port forward section you have to define the ports that shall be open in the router and forwarded to your OpenWRT device.

• 51820 = WireGuard
• 20.000 = custom port for a Nextcloud server
• 80 and 443 are only open temporarily for installation and renewal of Let’s Encrypt certificates

In the screenshot you can see that the DynDNS works as expected and the IP address is assigned to the port forward rule.

Network Settings

IPv4 settings

In our network a Pi-hole is the main DNS server. It shall be provided to all devices via DHCP server.

I have decided to run a Pi-hole before the OpenWRT ad blocker because Pi-hole

• is easy to install and configure
• is easy to maintain
• has a power full web GUI
• lot of features which can be configured via web GUI in any web browser.

Enter the ip address of your Pi-hole (or any other ad blocker in the network.)

IPv4 Routes

IP routes are important if you wanna access from your local network the OpenWRT device or devices that are connected to the OpenWRT in the lan network. (keyword SSH Jump Host)

You can access from any client located in your routers network clients that are located in the OpenWRT’s lan network (192.168.200.1).

Set the routes as needed.

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See all articles of this series …

… on strobelstefan.org
➡ Overview of all OpenWRT Articles

… hosted on Codeberg.

➡ https://codeberg.org/strobelstefan.org/openwrt-configuration

Source:
– https://openwrt.org/
– https://openwrt.org/_media/docs/guide-graphic-designer/openwrt-logo-usage-guidelines.pdf