Freifunk – SDN Clinic

Hardware platforms of a Freifunk network

This post is part of the series Building your own Software Defined Network with Linux and Open Source Tools and covers the hardware platforms used within the backbone network infrastructure.

In the early days into the project we didn’t have much funds but thankfully received quite some donations in terms of old hardware as well as money. As we were young and didn’t know what we know today, we went down quite some different roads, made lots of experiences along the way, eventually reaching the setup we have today. This posts lists most the platforms we used within the last years, basically only leaving out early wireless platforms and sponsored server machines.

As most Freifunk communities rely heavily on products from the portfolio of Ubiquiti Networks, quite some devices will be covered. In the following I will just call them ubnt.

Continue reading Hardware platforms of a Freifunk network

Deploying a Freifunk Hochstift backbone POP with Netbox Scripts

Some weeks ago Network to Code held the first (virtual) Netbox Day (YouTube playlist, Slides repo on github). John Anderson gave a great NetBox Extensibility Overview and introduced me to Netbox Scripts (Video, Slide deck, Slide 28) which allow to add custom Python code to add own procedures to netbox. I was hooked. About three to four hours of fiddling, digging through the docs, and some hundred lines of Python later I had put together a procedure to provision a complete Freifunk Hochstift Backbone POP within Netbox according to our design. I’m going to share my proof of concept code here and walk you through the key parts of the script.

Netbox scripts provide a great and really simple interface to codify procedures and design principles which apply to your infrastructure and fire up complex network setups within netbox by just entering a set of config parameters in a form like the following and a click of one button.

Continue reading Deploying a Freifunk Hochstift backbone POP with Netbox Scripts

Testinglos durch die Nacht…

Aus Gründen, die Euch nur noch mehr verunsichern würden, war es gerade alternativlos, diese Freifunkhymne zu bauen:

Wir ziehen durch die Knoten und die POPs dieser Stadt
Das ist unsre' Firmware, wie für uns alle gemacht
Oho Oho

Ich schließe meinen Browser, lösche jedes Cookie,
Gehe auf den Knot'n, so wie ich's im-mer tu'
Oho Oho

Was das zwischen uns auch ist, Links, die man nie vergisst
Und Dein Link hat mir gezeigt, das ist unser Mesh

Testinglos, durch die Nacht,
Bis ein neuer Build erwacht
Stablelos, einfach raus
Deine Knoten geh'n nicht aus!
Testinglos durch die Nacht
Spür was Gluon mit uns macht
Stablelos, signkeyfrei, großes Update für uns zwei
Wir sind heute ewig, tausend neue Knoten
Alles was ich hab, teil' ich mit Euch
Wir sind unzertrennlich, irgendwie verbunden
Komm nimm' meinen Link und mesh mit mir

Komm wir steigen auf das nächste Dach dieser Stadt
Schrauben einfach an was uns zusammen bringt
Oho oho

Bist Du richtig süchtig, Dish an Dish ganz verlinkt
Strahl in meine Schüssel und der Link geht an
Oho oho

Alles was ich will
Ist da, großer Uplink pur, ganz nah
Nein wir wollen hier nicht weg, alles ist perfekt

Testinglos durch die Nacht
Spür was Gluon mit uns macht
Stablelos, signkeyfrei, großes Update für uns zwei
Wir sind heute ewig, tausend neue Knoten
Alles was ich hab, teil' ich mit Euch
Wir sind unzertrennlich, irgendwie verbunden
Komm nimm' meinen Link und mesh mit mir
Testinglos

Funk pulsiert in meiner Hand
Testinglos durch die Nacht
Spür was Gluon mit uns macht
Stablelos, signkeyfrei, großes Update für uns zwei
Wir sind heute ewig, tausend neue Knoten
Alles was ich hab, teil' ich mit Euch
Wir sind unzertrennlich, irgendwie verbunden

Specifics and history of a Freifunk network

This post is part of the series Building your own Software Defined Network with Linux and Open Source Tools and covers the specifics of a Freifunk network as well as the history for the Freifunk Hochstift network which led to the latest re-design.

From a birds eye perspective, the Freifunk Hochstift infrastructure mainly consists of three building blocks:

Distributed servers hosted in data centers in Paderborn as remotely in Germany providing infrastructure services
Wireless backbones within the city centers of Paderborn, Warburg, etc.
Freifunk nodes at homes, shops, enterprises, or elsewhere

This post will focus on the distributed servers as well as the wireless backbones and will only cover the around 1.000 client nodes from the perspective of connecting them to the backbone (“gateways“).

Continue reading Specifics and history of a Freifunk network

Building your own Software Defined Network with Linux and Open Source Tools

Nearly two years ago, I started thinking about a next generation design for the Freifunk Hochstift backbone infrastructure, motivated by the limits and design choices made before (we were young and didn’t know better.. or didn’t listen..).

This post is the starting point of a series of posts about building a software defined wireless ISP network with Linux, a fistful of Open Source tools and low cost hardware.

Continue reading Building your own Software Defined Network with Linux and Open Source Tools

FFRL Routingdays – Learn to build the Internet

Over a year ago we (the Freifunk Rheinland Backbone Operators) organized the FFRL Routindays, a two day event where we gave a hands-on trainig on “How to build the Internet” or any internal network. As of periodic quesions about where to find the slides and videos here’s a summary of all media available of this event.

The event has entirely been in german language, as are all slides and lab guides. This is provided in the hope, that it still might be of some use even for non-german speakers.

The building blocks were

Networking / IP basics
Static routing + bird hands-on Lab
OSPF
eBGP
eBGP -> OSPF redistribution
iBGP
Policy-based Routing

The complete slidedeck is available here. Thanks to the CCC VideoOperation Center, there are recordings of the event avilable on media.ccc.de, too.