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Improving the blog tags (categories) by switching SQL query function from LIKE to REGEXP

Claudio Kuenzler @napsty.bsky.social · 28d

In my personal #blog I am using so-called "tags" to categorize blog posts. After I switched from the LIKE to the REGEXP string function in my #SQL query to the #MariaDB database, the correct blog posts now show up when clicking on a specific tag. 🤩
www.claudiokuenzler.com/blog/1507/im...

By switching the SQL query from LIKE to REGEXP, blog tag filtering was improved.

Systemd service not starting under CentOS / RHEL 7 but works on newer releases

2

Claudio Kuenzler @napsty.bsky.social · Sep 18

Different quotation marks handling in #Systemd, depending on its version and therefore #Linux distribution release, resulted in a broken service on EL7 (but worked on newer releases). Yeah, took me a while to find it. 🫣
www.claudiokuenzler.com/blog/1506/sy...

A Systemd service refused to start under Enterprise Linux (EL) 7 - but the same service unit worked fine under newer EL releases.

Bug in Varnish Enterprise 6.0.16r2 leads to removal of package - Geeker's Digest

Claudio Kuenzler @napsty.bsky.social · Sep 15

A #regression was discovered in the most recent release of #Varnish Enterprise (6.0.16r2).
As a result the affected package was pulled from the repositories.
www.geekersdigest.com/bug-in-varni...

A bug was discovered in the most recent release of Varnish Enterprise (6.0.16r2) and the package was pulled from the repositories.

Fixing Perl strict errors in HAProxy monitoring plugin check_haproxy

Claudio Kuenzler @napsty.bsky.social · Sep 15

Good morning 🌄

Claudio Kuenzler @napsty.bsky.social · Sep 12

On newer #Linux distributions, the #monitoring plugin check_haproxy might throw some Perl errors - causing a hiccup in your #HAProxy monitoring. Let's fix it!
www.claudiokuenzler.com/blog/1504/fi...

check_haproxy.pl is a monitoring plugin to monitor HAProxy. In new systems, the plugin could throw Perl errors. Let us fix this.

Rocky & Alma Linux 10 images available for LXC and Incus containers

Claudio Kuenzler @napsty.bsky.social · Sep 9

Good news for everyone working with #LXC and #Incus containers: @rockylinux.org and @almalinux.org 10 container images are now available!
- via Geeker's Digest
www.geekersdigest.com/rocky-alma-l...

Good news for everyone working with LXC and Incus containers: Rocky and Alma Linux 10 container images are now available to install.

Fixing broken SNMP monitoring on virtual firewalls (VS) after Checkpoint update to R81.20

2

Claudio Kuenzler @napsty.bsky.social · Sep 5

After a #Checkpoint VSX #firewall was upgraded, all interfaces of the virtual firewalls were down in monitoring! 😱
Here's how to verify the #SNMP settings on the CLI and (re-) allow direct access to the virtual firewalls. 👇
www.claudiokuenzler.com/blog/1503/fi...

After Checkpoint VSX was upgraded to R81.20, SNMP interface monitoring on virtual firewalls (VS) stopped working.

GitLab says your SSH key is expiring soon - but which one? - Geeker's Digest

Claudio Kuenzler @napsty.bsky.social · Sep 4

It's a common method to use #SSH keys for authentication on @gitlab.com repositories. Similar to access tokens, these keys will expire (inside #Gitlab) after some time.
Time to find out which one of your keys you used on this repo...
- via Geeker's Digest
www.geekersdigest.com/gitlab-your-...

GitLab says your SSH key will expire soon - but you don't remember which key it was. This post will help you!

How to allow all ICMP types in EC2 Security Group using Terraform

Claudio Kuenzler @napsty.bsky.social · Sep 1

With the aws_security_group module, security groups (firewall rules) can be created in @awscloud.bsky.social using #Terraform. But beware rules with the ICMP protocol, they behave slightly different.
www.claudiokuenzler.com/blog/1502/ho...

With the aws_security_group module, security groups (firewall rules) can be created using Terraform.

Prometheus Process Exporter and the 15 character groupname limit (using .Comm)

Claudio Kuenzler @napsty.bsky.social · Aug 29

The #Prometheus Process Exporter allows to retrieve metrics from all kinds of processes running on a system.
However you may run into a limitation if your machine runs multiple processes with similar names: You might lose #metrics of these processes!
www.claudiokuenzler.com/blog/1501/pr...

Using the Comm variable for process names in Prometheus Process Exporter might lead to missing metrics. Here is why and how to fix it.

How to create a dynamic redirect rule for multiple domains (hostnames) in Cloudflare

Claudio Kuenzler @napsty.bsky.social · Aug 25

Creating dynamic and domain/host agnostic redirects in #Nginx using the $host variable is fast and easy.
But how can you "translate" this into a @cloudflare.social redirect rule?
Once you find the relevant information, it's actually pretty easy, too. 👇
www.claudiokuenzler.com/blog/1499/ho...

This tutorial shows how to create dynamic redirect rules in Cloudflare working for multiple matching domains.

httpchk headers or body at the end of the version string is unsupported (in newer HAProxy releases)

Claudio Kuenzler @napsty.bsky.social · Aug 22

I was forced to have a look at the new HTTP Check methods as #HAProxy 2.8 on #Ubuntu 24.04 and 3.0 on #Debian 13 now run into configuration errors.
www.claudiokuenzler.com/blog/1498/ha...

If you relied on the option httpchk in HAProxy configurations, you might have to adjust the HTTP check on newer HAProxy versions.

Fighting the "mouse arm syndrome": The Logitech MX Master 3S is a great helper!

Reposted by Claudio Kuenzler

Florian Aigner @florianaigner.at · Aug 20

Ein junger Fußballfan hat eine physikalisch höchst interessante Frage. Na gut, lasst uns das mal kurz durchüberlegen. (Thread)

Natascha Strobl @nataschastrobl.bsky.social · Aug 20

Also folgendes: er würde gerne für eine Fußball-Sache einen Weltrekord aufstellen.
Und zwar für das Tor aus der weitesten Entfernung.
Und die Frage ist nun mit welcher Wucht er schießen müsste um von Wien nach Südamerika ein Tor zu schießen bzw wie weit der Anlauf ist? Kann man das ausrechnen?

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Claudio Kuenzler @napsty.bsky.social · Aug 19

When I started to experience slight pain in my right wrist - the wrist I'm holding my mouse - it was time to ergonomically improve my workspace.

The @logitech.bsky.social MX Master 3S came in pretty handy - quite literally.

- via Geeker's Digest
www.geekersdigest.com/fighting-the...

After I started feeling pain in my wrist (mouse arm syndrome), I needed an ergonomic mouse. The Logitech MX Master 3S was the perfect match.

How to verify Varnish VCL configuration

Claudio Kuenzler @napsty.bsky.social · Aug 14

Oh no! You restarted your #Varnish Cache but the VCL file contained an error?

Congratz. You've just caused a downtime. 🤪

It's much better to verify the VCL prior to a config reload or Varnish restart. It can even be automated in a pipeline or similar.

www.claudiokuenzler.com/blog/1497/ho...

How to verify Varnish VCL configuration for syntax errors or other mistakes.

OpenTelemetry Collector error: failed to create SDK bind: address already in use

Claudio Kuenzler @napsty.bsky.social · Aug 13

When a server already uses the listener port 8888, there's a port conflict and the @opentelemetry.io Collector won't start.

More background, technical details and a #Systemd service workaround in my latest #blog post.

www.claudiokuenzler.com/blog/1496/op...

OpenTelemetry Collector has a default listener for internal metrics running on tcp/8888. If this port is already in use, you run into a startup error.

Modellkarten für Schweiz (Max. Temperatur 2m, 12std) | Mitteleuropa Super HD (3 Tage)

Reposted by Claudio Kuenzler

Kachelmannwetter @kachelmannwetter.com · Aug 12

Schweiz: Am Mittwoch gibt es extreme Hitze! Die Temperaturen steigen auf 31 bis 38 Grad. Rund um Genf und im Rhonetal sind lokal bis 39 Grad zu erwarten. Für Details in die Kantone/Bezirke.

#Hitzewelle
#Hitze

/CG

kachelmannwetter.com/ch/modellkar...

Mitteleuropa Super HD (3 Tage) - Aktuellste Prognose für 13.08.2025, 20:00 Uhr des Parameters "Max. Temperatur 2m, 12std", Modellkarte mit dem Ausschnitt "Schweiz"

kachelmannwetter.com

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Claudio Kuenzler @napsty.bsky.social · Aug 10

I've always loved how intuitive yet technical the #Debian installer is.
It's great to see the installation of the latest @debian.bsky.social version 13 (Trixie), still looks and feels the same way.
www.geekersdigest.com/how-to-insta...

How to install Debian 13 (Trixie), step by step - Geeker's Digest

A step by step installation guide how to install the newest Debian 13 (Trixie) from an ISO image.

AWS EC2 instance (aws_instance) replaced on every Terraform run

Claudio Kuenzler @napsty.bsky.social · Aug 7

Ran into a weird problem, when an @awscloud.bsky.social EC2 instance got destroyed and re-created on _every_ #Terraform run.
Turned out to be a problem with an option in the aws_instance resource. Suggested by #AI.
www.claudiokuenzler.com/blog/1495/aw...

Ran into a weird problem, when an AWS EC2 instance was replaced on every Terraform run.

Bug in SolarEdge inverter firmware might set battery discharge limit

Claudio Kuenzler @napsty.bsky.social · Aug 4

Back in June I noticed a strange behaviour on my #SolarEdge Home Batteries. During #battery usage, there seemed to be a discharge limit, way below the maximum 5KW discharge.
As it turned out, this was caused by a regression after a #firmware update. Full story 👇
www.geekersdigest.com/bug-in-solar...

A regression in the firmware of SolarEdge inverters might set a discharge limit of Home Batteries (48V), way below the usual 5KW.

Debian 13 (Trixie) release date published - Geeker's Digest

Claudio Kuenzler @napsty.bsky.social · Jul 21

The wait is soon over! Planned release date of #Debian 13, code named "Trixie", was published.
The new @debian.bsky.social version contains #Linux Kernel 6.12 and will be released in August.
- via Geeker's Digest
www.geekersdigest.com/debian-13-tr...

The Debian project plans to officially release its 13th version, with the code name Trixie, on August 9th 2025.

Solving GitLab pipeline error (): mapping values are not allowed in this context

Claudio Kuenzler @napsty.bsky.social · Jul 18

A #GitLab pipeline ran into a rather cryptic error, mentioning mapping values in a specific line.
After some head-scratching, the error was found. Inside a string colons were used. These were interpreted as "key: value" by the @gitlab.com #pipeline parser.
www.claudiokuenzler.com/blog/1494/gi...

A job in a GitLab pipeline ran into a rather cryptic error, mentioning mapping values in a specific line.

WeTransfer change of terms: Do they really own your files now? - Geeker's Digest

Claudio Kuenzler @napsty.bsky.social · Jul 17

Is it true, that files uploaded to #WeTransfer are now owned by them and not you anymore? Will they be used for training #AI models?

The latest Geeker's Digest post tries to makes sense of it. Without emotions, just facts.

www.geekersdigest.com/wetransfer-c...

After WeTransfer updated its terms, controversy about ownership of uploaded files started. Is WeTransfer now the owner of your files?

How to limit disk usage of Systemd Journald logs - Geeker's Digest

Claudio Kuenzler @napsty.bsky.social · Jul 15

A #Linux system running with Systemd's Journald can eventually run into a low disk space event.
The latest #tutorial on Geeker's Digest shows how to manually clean up old journals and how systemd-journald can be configured to use a disk limit.
www.geekersdigest.com/how-to-limit...

How to configure systemd-journald to use a disk size limit of the log files. By default there's no limit on the disk usage.