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Linux

Raspberry Pi OS: Unnötige Pakete entfernen

Kürzlich schrieb ich darüber, dass es eine erste 64 bit Beta-Version von Raspberry Pi OS (ehemals Raspbian) gibt. Diese gibt es bislang leider nur in der Desktop-Variante und noch nicht als Lite-Version. Mit zwei Befehlen kannst Du jedoch ganz leicht die – sofern Du sie nicht benötigst – überflüssigen Desktop-Pakete deinstallieren.

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Docker Linux

Traefik Access Log mit InfluxDB und Grafana auswerten

Traefik ist ein im Docker- und Kubernetes-Umfeld häufig eingesetzter Cloud Native Edge Router. Mit wenig Aufwand lassen sich die Zugriffslogs (Access Logs) von Traefik mittels Telegraf automatisch in eine InfluxDB überführen, um sie mit Hilfe von Grafana auszuwerten. In diesem Artikel zeige ich Dir, wie es geht.

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Linux

Nativer USB-Boot für Raspberry Pi 4

Darauf habe sicher nicht nur ich gewartet: Endlich kann der Raspberry Pi 4 von USB-Laufwerken starten! Und das ganz ohne die weit verbreiteten Workarounds, bei denen noch eine SD-Karte als primäres Boot-Medium benötigt wurde. Möglich macht es eine neuen Firmware, ein sogenanntes EEPROM. Und nebenbei gibt es auch eine 64 bit Beta-Version von Raspberry OS, ehemals Raspbian.

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Docker Linux

How to let Jenkins build Docker images

If you’re using Jenkins as your Continuous Integration (CI) tool and Docker to build self-contained images of your application, you may ask yourself how to automatically build Docker images during Jenkins‘ build job. Here’s how I did it – with Jenkins running in a Docker container itself.

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Docker Linux

Using Let’s Encrypt / EFF’s CertBot with NGINX in Docker

I’m using NGINX in a Docker Container as a front-end HTTP(s) Webserver, performing SSL termination and proxying incoming requests to various other Docker Containers and VMs. Now that I’ve switched my certificates to Let’s Encrypt, I wondered how to integrate EFF’s CertBot (which is recommended by Let’s Encrypt) with my setup. Here’s how I did it.

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Docker Linux

From FHEM to OpenHAB with Homegear: Installation/Docker container

For more than 2.5 years, I’ve now been running FHEM with several HomeMatic sensors and actors. Using the HM-CFG-LAN Configuration Tool as an I/O interface between FHEM and the HomeMatic devices, this setup has been running smoothly most of the time. The configuration was a bit tricky now and then, but it worked. However, OpenHAB seems to become a really good choice. Version 2 is currently available as Beta 3. It features a modern web interface and an easy-to-use extension manager. More than a good reason to have a look at it. In this post, I’m going to show how to get started.

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Linux

How to set up HTTPS/SSL in WordPress behind Proxy (nginx, HAProxy, Apache, lighttpd)

Today I changed the accessibility of my blog from HTTP (unencrypted) to HTTPS/SSL. My blog is running WordPress behind an nginx proxy server. However, while the pages themselves loaded successfully from HTTPS, the embedded static resources like JavaScripts, Images, CSS files etc. did not. Here’s how I fixed it.

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Linux

How to reduce PDF file size – Part 2

Several months ago, I wrote a blog post about reducing a PDF file’s size. Since then, I’ve used that technique many times. However, you may want to control the DPI (dots per inch) even more specific. Here’s how to do it:

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Linux

How to enable IPv6 on a SonicWall (SonicOS 5.9) using NAT

IPv6 aimed to make Network Address Translation (NAT) obselete as there are so many addresses available that every single device can have its own worldwide unique IPv6 address. However, even with IPv6, using NAT is a very simple way to get your devices behind a Dell SonicWall connected to IPv6 services on the internet. In contrast to going without NAT, all the devices behind your SonicWall will emerge under the SonicWall’s IPv6 address.

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Linux

How to reduce PDF file size in Linux

Using a single line of GhostScript command on my Ubuntu’s terminal, I was able to reduce the size of a  PDF file from 6 MB to approximately 1 MB:

gs -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen -sOutputFile=output.pdf input.pdf