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Dynamic DNS service with fritzbox

If you are the owner of an avm router, you can setup a dynamic DNS service with the fritzbox.

Recently my current dyndns provider no-ip had an outage, and it took me around one hour to detect the root cause of the problem. The service guys of no-ip responded fast, I have to admit. But it took one complete day till the service was finally back.

So I was looking for another solution. And was successful with the service of avm.

I will explain the necessary steps setting up the service.

First you have to configure the MyFritz account by opening your fritzbox and going to „Internet/MyFritz! Konto“.

There you enter the credentials as requested and show in the screen shots:

MyFritz! account
MyFritz! account details
MyFritz! Account with SSL Zertificate

You can also configure specific users only accessing the fritzbox from the internet and you can configure an SSL certificate using LetsEncrypt (recommended.

Then you configure the port forwarding from the MyFritz!Konto IP address to the device behind your fritzbox, in my case a raspberryPi3:

Port forwarding
Dynamic DNS service with fritzbox
Port forwarding for the MyFritz! Account

After that is all done, you are ready to set the domain forwarding at your domain provider. The interface may vary based on your domain provider management GUI.

Domain forwarding
Domain forwarding

Another advantage is also that you don’t have an outage of your site when your IP address is changed by the ISP, as the router immediately recognizes that and reconfigures the entries in the MyFritz!-Account data base.


The MyFritz! Account is a very good solution for a dynamic DNS service with a fritzbox.


Recently I had some problems with the fritz service. Either there were outages for a few hours or I had to disconnect from the service and reconnect again. So I was going for a backup solution.

And I found a very good free service dyndns.de that is running now for some time without any problems.

This means I have setup now two Dynamic DNS services to connect to.

For switching between these two services I just have to change the CNAME entry in the DNS service of my hosting provider as shown above.

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Multiroom sound and media solution

After some time of investigation and reseach, I think I have found and implemented a quite nice solution in my IT home network in respect to a multiroom sound and media solution.

Multiroom sound and media solution
A part of the media network components

I have compiled a few static pages on my home page explaining the details.

In total the complete environment including the web server consists now of three Raspberry Pi 3 B+ devices and one very cute Raspberry Pi Zero W device.

The software is based mainly on max2play.

Check out the details of my multiroom sound and media solution and let me know if I can help you with any setup or recommandation on your side.

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Multiroom sound setup

It’s not so easy to compile a multiroom sound setup. Let’s go through a few options that are currently available.

Furthermore we will also discuss the use case of moving the setup to an outdoor environment, e. g. for a party.

Multiroom sound setup
Managing the sounds…

Bluetooth connection

If you wanna connect multiple speakers via Bluetooth, you have to be aware that the physical connection works mostly only to a distance of up to 10m.

Second, the devices you wanna control the Bluetooth loudspeakers very often allow only a point to point connection based on Bluetooth.

The Samsung galaxy S8 allows 2 Bluetooth connections at the same time, but this is not a big help for setting up multiple rooms.

WLAN or LAN connection

With WLAN you obviously have also some constraints in the reach, but this can be solved with wlan repeaters.

You can use either directly a (w)lan speaker or you attach a (w)lan to voice conversion device to every speaker.

The following options I have found so far for such a device :

All the solutions are not so cheap.

Software for controlling the multiroom setup

A multiroom sound setup depends first on the hardware. Independant software solutions without requiring specific hardware are not easy to find.

What looks quite promising are two free software solutions:


Bluetooth speakers

There are plenty of bluetooth enabled speakers avalailable on the market. It depends more on the other use cases (outdoor, indoor, sound quality, fixed or movable) which speaker is the best solution for you.

WLAN speakers

Also there are plenty of speakers now available with built in WLAN capabilities.

Use cases

Outdoor use case

For going outdoor you should select speakers that can handle water, like e.g. the Sony SRS-XB31.

Also setting up a WLAN including a router and connecting the speakers is not so easy to handle.

In this case it maybe makes more sense to restrict oneself to a bluetooth party chain solution only. This is some offering by Sony.

Upgrading an existing environment

Some people, of course, have an already existing environment and want to upgrade or extend it.

A very good description how this can be done is given by Euronics.

Proprietary solutions

A very good overview for commercial and complete proprietary solutions is given by Conrad.

Currently selected solution

If you are fine with using the Mac or a windows machine as a server, Airfoil is a quite nice solution.
You can stream any application running on your server synchronously to plenty of devices, including multiple bluetooth devices.

I’m going for the max2play solution now.
Yes, it’s more costly as you have to have multiple Raspberry clients running. But you are more flexible as well.
And it makes more fun playing around with the Raspis 😉


  • Use of Rpi output or USB soundcard or expensive DAC to connect to the speaker
  • Play different music in different rooms
  • Control it remotely, also via an app like squeezer
  • Don’t need a Windows or Mac as a server


  • Cannot connect to multiple bluetooth devices with one RPi
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KI auf dem Raspberry Pi

Google hat seine Software Tensorflow weiter entwickelt, so dass nun auch KI auf dem Raspberry Pi zur Verfügung steht.

KI auf dem Raspberry PI


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RaspberryPi 3

Es wurde Zeit für einen Update. Was sich als gar nicht so einfach herausgestellt hat. Bis jetzt lief meine Web-Seite auf einer Cubox mit 2 CPUs (jede mit 700MHz) und 768MByte RAM, aber immer etwas mühselig, sprich langsam. Besonders die PHP Performance war nicht besonders.
Also wollte ich einen Update machen auf einen Raspberry3 mit 4 CPUs (jede mit 1GHz) und 1GByte RAM.
Aber ganz so einfach wie gedacht, war es nicht. Ich konnte nicht einfach die CuBox mit dem rPi3 ersetzen. Der rPi3 bootete nicht. Also habe ich mich für einen radikaleren Weg entschieden.
Der rPi3 bootet nun direkt von der Festplatte sda1. Die Anleitung dazu kam von https://www.raspberrypi.org/documentation/hardware/raspberrypi/bootmodes/msd.md

Und dann habe ich die Dienste wieder separat aufgesetzt:

  • mysql daemon
  • phpmyadmin
  • apache incl. vhosts
  • wordpress, Kopie von Datenbank und PHP files
  • baikal calDAV und cardDAV server
  • noip dynamic IP service

Aber es hat sich gelohnt, die gefühlte Performance ist doppelt so gut wie vorher 😉 (Nein, ich mache keine Performance Tests mit pingdom etc. 😉 )