37C3 – Martin @ Congress

Those of you who have been to ‘Congress‘ before know it’s a special event for anyone even remotely nerdy. It always takes place between Christmas and New Year’s Eve and I was lucky enough to get a ticket. It seems they still remembered I gave a talk there about 5G last time around. After not having taken place for a number of ‘Covid’ years and after moving back from Leipzig and 17.000 participants to the significantly smaller Congress Center Hamburg, I was not sure how things would work out and whether I would like it. So I jumped in to find out.

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Lenovo T14 Gen 4 and Intel AX211 Wi-Fi – When ‘Rouge’ APs Disable My 6 GHz Wi-Fi

When I was recently on business travel, I used my smartphone for Wi-Fi tethering my notebook to the Internet over the 6 GHz band. But every now and then, my notebook wouldn’t find the smartphone’s network and I had to switch to the 5 GHz band to make it work again. After a bit of back and forth between the two bands over a couple of days I noticed a pattern.

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Lenovo T14 Gen 4 and Intel AX211 Wi-Fi – Performance in 5 and 6 GHz – Part 5

One of the interesting new features of the Lenovo T14 Gen 4 I haven’t had in my previous production notebook was the support of Wi-Fi in the 6 GHz band. So I was obviously quite curious how this would work and how performance would look like. So here’s the story.

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Pixel 6 – LineageOS and VoLTE Roaming

One of my reasons to switch from my previous phone with LineageOS to a Pixel 6 with LineageOS was to get Voice over LTE (VoLTE) support. It has worked well in my home network and I’m very happy about the upgrade. But what about VoLTE Roaming support when visiting another country? I had no idea if this would work until I was abroad recently and checked it out. And indeed, VoLTE Roaming was activated and working. Apart from the better speech codec used compared to traditional circuit switched roaming, call setup time was also almost instantaneous. Very nicely done!

The Interesting Case of Fixing Things with 32GB RAM

So here’s a fix that left me with some question marks:

A family member likes to test the limits, and pushes out rebooting the notebook running on Linux for as long as possible, sometimes well over 6 weeks. A side-effect of this is that applications that like to bloat, such as Firefox, Chromium, Thunderbird, Libreoffice, etc. etc., keep eating up more and more RAM. At some point, usually after a week or so, all of the 16 GB RAM + 8 GB swap space on the SSD becomes used.

Closing the apps occasionally would help, but that’s also not in the cards. EarlyOOM helps to keep the system stable, but at some point the system just keeps banging its head against the 16 GB of RAM. So what to do? At some point I was convinced to install 32 GB of RAM. I reluctantly agreed, but honestly, I thought it wouldn’t help much. From my point of view, doubling RAM would just extend the time to the inevitable, and EarlyOOM would be asked to help again. But it looks like I was wrong.

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Moving on to MediaWiki – Part 2 – Docker Install

In the previous post on this topic, I’ve had a look back at which Wiki’s I’ve used over the decades to store my personal tech information and why I decided to move on to MediaWiki as a platform. In the past, getting a new web service up and running required the setup of a web server, a database and some other things and was a bit of a hassle. Fortunately, there is an official containerized version of MediaWiki these days and I found a good description of how to get it up and running with docker-compose in no time. As the description is in German and because I have changed a few things, here’s my version of how to get up and running:

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Moving on to MediaWiki – Part 1

One tool that has become absolutely essential to me for note taking and finding information again is a Wiki. A very long time ago, I initially used WOAS, a personal Wiki platform that was basically a local HTML file that could be modified in the browser. It was a nice system, but at some point, modifying local files from the browser became a security risk and was hence disabled. So I had to look for something else. That was 10 years ago in 2013, and I wrote about it on this blog at the time.

At the time, I decided to migrate my pages to the MoinMoin Wiki system, based on Python and an Apache web server. I liked MoinMoin a lot, because it was easy to use and it stored all pages as a file in a directory structure. Why complicated when things can be simple? Unfortunately, MoinMoin development pretty much came to a halt, and when I upgraded to Ubuntu 22.04, it stopped working. It turned out that MoinMoin was still based on Python 2.7, which has been unsupported for a long time now, and hence version 2.7 was not included anymore in the current Ubuntu Long Term Support version. As I got the impression that the situation is unlikely to change anytime soon, I started to have a look around for alternatives. From what I can tell there are two main options at the moment: DokuWiki and MediaWiki.

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Letsencrypt, Ubuntu 22.04, DAVS and the File Manager

After upgrading my notebook to Ubuntu 22.04, one of the few quirks that I had to deal with was that the file manager suddenly threw a security warning when I wanted to mount my Nextcloud DAVS share that is protected with a Letsencrypt certificate. Very strange, as this worked flawlessly in Ubuntu 20.04. It doesn’t break the functionality, but getting a certificate warning each time I mount the network drive is not acceptable. It turns out that for whatever reason, Ubuntu 22.04 doesn’t have the Letsencrypt chain of trust in their certificate store. Web browsers like Firefox don’t have the issue on 22.04, as they come with their own certificate store. For some strange reason, there isn’t really a description of the problem on the net, or it’s well hidden by other search results, so it took me a while to figure out how to import Letsencrypt’s current certificate chain. But I finally figured it out and here is how it is done:

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Lenovo T14 Gen 4 – Intel – Suspend/Resume Surprises – Part 4

And on we go with my series on Ubuntu 22.04 support for the Lenovo T14 Gen 4, Intel variant. In this part, I’ll have a closer look at how suspend / resume works when the notebook lid is closed. Spoiler: It works perfectly out of the box, but things are different from what I was used to so far!

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