simonmicro

Mellanox QSFP/SFP28 PCIe Brackets

Fri, 09 Jan 2026 12:19:27 +0100

Just a very quick post, as I invested some time into a proper, parameterized FreeCAD model for the PCIe brackets of Mellanox network cards. I recently installed two of these cards into some server and only had the short brackets available, which are, of course, not fitting into a standard PC case. As I could not find any ready-to-print models online for all the variations I needed, I have created my own. You can download this model from here or from Thingiverse.

Ceiling Light: B.K. Licht and Home Assistant - 2025 Upgrade

Sun, 23 Nov 2025 12:47:00 +0100

Huh? What?

…so, this post is a follow-up to the original Ceiling Light: B.K. Licht and Home Assistant blog post from 2023.

So, over the years of use, I noticed a minor issue with the original wiring: Whenever the light is turned off, the transistors controlling the individual color channels are unable to fully turn off the outputs. This leads to a small current flowing through the LEDs, which in turn causes them to glow faintly red, even when turned off.

FFmpeg - Conversion

Sat, 25 Oct 2025 23:00:14 +0200

Some copy-paste scripts for mass media conversion

WireGuard VPN on a JetKVM

Fri, 28 Feb 2025 23:42:00 +0100

The setting…

I recently started adopting WireGuard VPN into more and more of my server infrastructure. Consequently, I was wondering if the Linux-based JetKVM could also be integrated into these networks - especially useful since I do not want to use their cloud solution, but still want to deploy these onto remote locations as needed. So, getting WireGuard to run there was both harder and easier than expected - here is a write-up on how to do it. If you just came here to quickly copy-paste some commands, there you go:

Unbranding a Fritz!Box 6490 KDG Edition

Fri, 06 Dec 2024 14:12:00 +0100

What was going on?

Recently, I had once again the unique opportunity to flash a “Fritz!Box 6490 KDG Edition” with the guarantee of no consequences in case I completely brick it. This time, because I needed the DECT functionality still working after this operation, I chose to stay on the proprietary firmware by AVM. 🤷‍♂️

So, here is my battle plan:

Get the stock firmware for the device from its vendors download-server with its recovery-tool in case it goes really wrong.
Convince the bootloader to report an unbranded model to the OS (guide from here)
“Recover” and boot it
Enjoy a more open experience!

What really happened…

Obtaining the stock image

This is where I hit the first road-block: The manufacturer offers seemingly no recovery.exe-tool for this device. So, to proceed, I just grabbed the original firmware image from their download server and extracted the partition images from it:

Phishing Attempt on Steam

Sat, 20 Jul 2024 18:25:00 +0100

Well, that happened…

…just a word of warning: Be careful on the internet!

I was randomly contacted by some dude on Steam late at night, stating that he wanted me to connect with his buddy - fine, right? While he did not identify himself properly, I shrugged it off, as he just wanted to hook me up with his friend quickly. I was like “Sure, why not?”, let’s give it a shot. Here is a screenshot of our little chat:

OpenWrt for Fritz!Box 7360 EWE Edition

Sat, 29 Jun 2024 20:10:00 +0200

What was going on?

Recently, I had the unique opportunity to open-source flash a “Fritz!Box 7360 EWE Edition” with the guarantee of no consequences in case I completely brick it! So my first choice fell on OpenWrt, as it is a well-known and well-documented open-source firmware for routers and modems. Especially, this would fix issues with increasingly decreasing wireless performance with the original firmware after multiple weeks of uptime (thanks AVM).

Libvirtd - Linux virtualisation

Tue, 02 Apr 2024 22:05:22 +0200

Server, client, shared folders, freezing at host down-times and much, much more!

Borg - Backup

Fri, 10 Nov 2023 01:27:49 +0100

Notes regarding the borg backup system. Also a setup script for automated, encrypted, and deduplicated backups is included…

OPNsense for R&S GP T-10

Sun, 05 Nov 2023 16:22:16 +0200

What?

I recently got some old firewalls - the “Rohde & Schwarz GP T-10” (they are even still oficially supported by the latest software release by the manufacturer!). These are embedded devices build to be deployed in workshops (or any other harsh environment) and are therefore fanless designed. They are also very small and have a very low power consumption. The hardware is quite old, but still more or less capable for a firewall. The only problem is, that the operating system is not open source and therefore not very flexible. So I decided to replace the operating system with OPNsense.

Rice Pudding - without rice

Sat, 26 Aug 2023 19:00:00 +0100

Ingredients

40g Sugar
1 packet Cream-Pudding Pulver
500ml Milk
6x drops Vanilla flavor
5x Butter Biscuit (“Butterkeks”)

Assembly

Stove.insert(pot);
pot.insert(mix(milk, sugar, aroma));
Stove.heat(pot, 100%);
while(pot.content is not cooking)
 stir(pot.content);
Hand.insert(butter_biscuits);
Hand.crush();
pot.insert(pudding_pulver);
pot.insert(butter_biscuits);
for(2 minutes)
 stir(pot.content);
while(pot.temperature > environment.temperature)
 wait();
Fridge.insert(pot);

Docker - Containers

Thu, 13 Apr 2023 11:47:19 +0200

Own registry, container auto updates and maintenance stuff!

NOTE

Sun, 01 Jan 2023 00:00:00 +0200

Pretty empty on my projects page, right? Well, sadly I have a lot to do, so I have not much time to regulary update this anymore… In case you want to see my public-facing stuff, checkout my GitHub instead.

Otherwise, see you around!

Nginx - Proxyserver

Wed, 21 Dec 2022 14:56:20 +0100

Templates for reverse proxies with websocket support? Wildcards. And Docker stuff.

Kubernetes - Powerful Docker Cluster

Sat, 16 Jul 2022 21:07:53 +0200

Kubenetes services with external fixed ips using keepalived

ZFS - A filesystem on steroids

Thu, 30 Jun 2022 14:30:00 +0200

Install, usage, tips and tricks, encryption, compression & more!

Ceiling Light: B.K. Licht and Home Assistant

Fri, 08 Apr 2022 15:21:00 +0100

Leadup

Everything started as I bought the “LED Panel, Colour Temperature Fully Adjustable […]” by “B.K. Licht” off Amazon. It worked great with the also shipped remote control and it was only a little bit inconvenient to never have the remote when needed. It is a 15W LED panel with RGB/WW/CW and therefore 5 channels. I chose it because the pictures in the reviews indicated a modular power supply and also showed some minor information about the wattage and ratings. Furthermore, the manufacturer (or at least distributor) was also located in Germany, so I hoped for easier communication.

LaTeX is shit

Sat, 12 Feb 2022 18:12:00 +0100

Here is my list of problems…

Bad parameter transfer: {} is so illegible in quantities
Commands are illegible: In LibreOffice I write e in R or m = abs (M) and have what I want. Done.
Nesting is shitty to read: If it ends with }}})} you have a lot of fun!
Not live: Okay, I’ll put it behind bracket number four… Wait five seconds… Damn, put it next to it and again… - And only when Overleaf isn’t going crazy!
Hmm, we have a style parameter with {}. THEN LET’S GO BRUTAL. Elsewhere you can add " " for a string or space to be respected, which does not affect the reading flow. But {} - here you are always forced to {}. For. Every. Shit.
LaTeX does a lot for you - if you don’t want that, you have to deal with warnings and complaints.
Unintuitive syntax: \subtitle * {BS} - you have an idea what * is doing here? No. Neither do I - but please do not include a readable parameter or other command for it - because LaTeX!
Just open it offline? With pleasure. Then I’ll just download the 1-2GB LaTeX compiler collection. LibreOffice, for example, is 500 MB in size - and that with a complete GUI, image processing and spreadsheets!
Okay, \rightarrow etc. is nice - but did you know that you can also pass parameters to that?!? At least that’s Overleaf.
And LaTeX tries to be able to do everything: Instead of dividing the standard into math, markup, graphics, etc., you have to be careful that math commands are available in the text flow, but do not do what they should -> simply prevents context-based simplification.
And I don’t think that it can be easily expanded - in LibreOffice? I want to embed an auto-updating website screenshot? Sure thing. In the worst case add a Python script as a plugin. Done. Latex? Nope.
And yes, I’ve already seen one or the other LaTeX text - how did I recognize it? Images from the following chapters have ended up in the previous ones. Why? Because LaTeX felt it was “more suitable”.
…this gets even worse if you try to separate two chapters by introducing a new page starting with your headline (using \newpage): Now you have a new page with your new chapter AND the graphics from the previous chapter! Try using \clearpage - it does not clear, but flush instead!
Shitty to archive: Oh, I opened an old document - let’s hope that the exotic plugins (which you use very quickly, because LaTeX ends very quickly) can still be found somewhere … LibreOffice etc? The document from 1999 still just works - Word even down to the first version. And for archiving, it is sufficient to save the portable version as well. Done. Latex? Have fun scraping together all the extensions from the most diverse corners.
LibreOffice has a document. It has everything used in it: fonts, images - everything. I open it for myself and it does for you too. Done. LaTeX you have to push everything around somehow - not to mention that one LaTeX compiler may not swallow the x format like the other.
Include media? With pleasure: Just no two clicks with clear submenus. But HELL NO, you need to integrate a plugin and then google elsewhere what the damn alignment command for images with that specific plugin is. Because there is another command for text based alignment.
Copy&Paste from LaTeX documents? No! Try it for yourself, you’ll may find spontaneously missing underscores or reordered letters. Also good luck selecting tables - they only look like them!
Did you know that LaTeX will always rescale your images? There is no way to turn it off, except…
…to prevent image rescaling you have to convert them to a PDF. These won’t be scaled in any way, as LaTeX is currently not supporting this. Now imagine you learn this after you are already using >42 images and you now have to painstakingly convert them.
Change DPI? Nope, just does not do anything. Because why should the recommended command work?
An other way to prevent image rescaling is to use vector graphics - which is fine. EXCEPT that LaTeX does not support SVG (which is THE filetype used in browsers, fonts, icon packs…) and it is recommended… To use PDF.
PDF optimization does not exist. You have a complex PDF-graph by mathplotlib? Let it slow down and crash the reader. But GOD FORBID you have a png-image, that MUST be scaled down so no text is readible anymore!
Sometimes the text placement on pages is just… weird.
BibTeX. A tool for standardized citations. But - ITS OWN FORMAT IS NOT STANDARDIZED! Beside questionable historic categories, nobody seems to know which tokens should be used when…
Also BibTeX: It is 2022 now (or maybe even later) and this package does not even come with URL (or URI) support (you know, often enough you need to use this). You need to search the internet to find a suitable replacement. Again.
Your professor gives you a LaTeX template you are forced to use - okay! Just import it and use it, right? NO! I imported it into Overleaf (because I still refuse to install that crap) and all formatting is broken and packages are missing. So much for portability!
Inside some documents/fonts charaters like ff, ti or ft are represented using a special remapped character - resulting in a broken search feature as you e.g. would need to enter ← to search for ff, e.g. “scaffold” must be searched as “sca←old”. Imgaine the pain with words containing a “-tion” or special characters you can’t enter!
Ever tried to use a \footnote{} inside a \caption{} of a \figure{}? This will not work out due to the compiler error-ing out. It is a known problem, where you have to use the optional parameters of the caption - fine, but that also does not work… Then, if you dig deep enough, there is a workaround using a \footnotemarker and a subsequent \footnotetext - but guess what: That works including throwing the same errors as before!? If \citep{} works without issues inside \caption{} in the provided template, why does \footnote{} not.
Also something I just encountered: I was typing and typing, the amount should already fill another page, but upon rendering, the page-count stayed the same. Fine, I think while scrolling back up, LaTeX must have found a way to realign the content to fit in the new text without adding a new page. Yes, it did. On another page, in another chapter, are now four two centimeter tall white spaces, as the previously placed graphics were moved somewhere entirely else. Nice, makes reading so much more aesthetic.

…not bad?

Okay, it’s nice that I can script my documents too.
Okay, yes the source can be versioned well via Git.

That would be all. Let’s see what else I find in the future.

Apache - Webserver

Thu, 10 Feb 2022 23:18:06 +0100

Templates for vitual hosts (https with LetsEncrypt, proxies, authentication and more) and hardening

Mekanism Generator Uran Production

Wed, 12 Jan 2022 15:23:00 +0100

Random side note - here is a corrected version of the uran production line for Mekanism v12.

Download

Thank me later!

Fail2Ban - Server security

Sun, 19 Dec 2021 22:26:05 +0100

How to install and basic config for incremental banning…

Mailu - Email

Sun, 19 Dec 2021 22:24:41 +0100

Manage your own email server easily - and how to setup servers to email you. And SPF and stuff…

OpenVPN - Run your own VPN

Sun, 19 Dec 2021 21:21:43 +0100

How you can use port forwarding even behind NAT (which is commonly used on mobile networks), including an example for integration into UniFi Gateways and a guide for a classic VPN server for any amount of clients!

Alpine - Linux can be small