This post describes different software components involved in host name resolutions and DNS configuration on GNU/Linux systems. It consists of a diagram and some accompanying explanations. The goal is to give some pointers and references to understand how to troubleshoot host name/DNS resolution problems and configuration problems on GNU/Linux systems.

Some scripts I wrote to enable system-wide push-to-talk (for X11 and PulseAudio). Some people might find it for the ongoing lockdown.

Some guidance about configuring/fixing domain name resolution with a corporate VPN (especially OpenVPN) with systemd-based Linux systems. This configuration uses the internal/private corporate resolvers for resolving internal/private domain names while using the ISP resolver for general domain names. This might help if your VPN is struggling these days because of the COVID-19 threat .

Using FlameGraph for displaying disk usage.

I was looking for a LLMNR commandline lookup utility. Actually, dig can do the job quite fine.

I thought I was understanding pretty well how bash argument processing and various expansions is supposed to behave. Apparently, there are still subtleties which tricks me, sometimes.

How I found remote code execution vulnerabilities via Cross Site Request Forgery (CSRF) on the administration interfaces of InternetCube applications and of the YunoHost administration interface which would have been used to execute arbitrary code as root. These vulnerabilities were fixed in YunoHost 3.3, OpenVPN Client app 1.3.0. and YunoHost 3.4.

Here's the workflow I'm using to generate simple text documents (resume, cover letters, etc.) from Markdown, YAML and Jinja2 templates.

Trying to bring back some old IP spoofing Firefox extension for watching South Park episodes.

In the previous episode, I talked about some argument and shell command injections vulnerabilities through URIs passed to browsers. Here I'm checkig some other CVEs which were registered at the same time.