Load Balancing and High Availability

In my last article Home Network Upgrade - Basics, I described the setup of a Raspberry Pi-based cluster I plan on using for the core of my upgraded home network. One issue there, however, was that the devices need to be addressed directly. E.g., a service running on Kubernetes is available via the IP addresses of both nodes, if everything is working fine. But the client needs to select one address. E.g., if a client uses node01, and this node fails, the client needs to adjust. This is undesirable for our setup. This we need to introduce a means for fail-over. Additionally, we use the same setup for load balancing the incoming requests. In this private setup load balancing is less of a requirement, but high availability is much desired.

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Home Network Upgrade - Basics

In this article (and likely following ones) I will be setting up a new home network infrastructure, using cloud technologies such as distributed file systems, containers, and orchestration mechanisms to abstract from the hardware, allowing redundancy in the infrastructure, as well as easier scalability in future.

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Home Assistant, GPSLogger & no open port

I have recently started venturing into the area of home automation a little more. As you can expect, my focus is running a system as flexible, functional and yet secure as possible. This involves to not use components connected to the Internet. The details of this, however, shall be the content of another article. There, I will introduce the hardware (currently undergoing changes) and platform I use. This article instead covers the higher-layer challenge of tracking Android phones positions (and via this the positions of people) with GPSLogger and bringing that information to Home Assistant. While this works out of the box in Home Assistant, it requires Home Assistant, or, more specifically, the GPSLogger integration, to be available to the phone. This typically means an open port to the web server of Home Assistant. Seeing all the other control options available via the web interface, I did not want to risk exposing these, in case of a security incident. Thus, this article will present a solution to tunnel GPSLogger data into Home Assistant via a web server.

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Desk & Setup

After many years of using small, cramped corners to set up my computer equipment, I used the chance of a new spacious flat to also build a nice, big desk. I feel there are few things more luxurious to have than space, especially, when not needed. That’s the main philosophy for this new setup. Additionally, a sleek, minimalist design was required, while at the same time offering sufficient storage space for a large number of devices, cables, etc.

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Analog document digitization

I used to be good at sorting paper documents when I was younger. With the amount of letters (mostly bills) getting more and more in life, I gave up on sorting paper. I have yet to find an organizational scheme that easily allows me to store and retrieve a large number of documents within a short amount of time. Instead, I decided to do what I do best and use technology to help me. This post details the process I use for digitizing analog documents for home use.

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TODAES Best Paper Award 2019

I am very happy to announce that an essential part of my PhD thesis, our (with Andrew Paverd, Artur Mrowca, Sebastian Steinhorst, Martin Lukasiewycz, Suhaib Fahmy, Samarjit Chakraborty) paper entitled “Security in Automotive Networks: Lightweight Authentication and Authorization” has received the ACM Transactions on Design Automation of Electronic Systems (TODAES) Best Paper Award 2019 at the 56th Design Automation Conference in Las Vegas yesterday!

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