I recently needed to run an application in a Docker container but really wanted to prevent it from accessing the Internet for privacy reasons. Normally, I would’ve just used the none Docker network, so that that traffic cannot be routed to the Internet. But since the application exposed a web interface that I wanted to access, it unfortunately required a bridged network to expose a port. I read about potential solutions using iptables, but they seemed to complicated for my use case. ...
Weird suspend issues with my Framework 13 laptop on lid close
Ever since I’ve gotten my Framework 13 laptop, I’ve had a weird issue with random suspends. Very often, I would wake the laptop from suspend, and then it would immediately go back to sleep for no apparent reason. Most of the time, I was lifting the laptop up from somewhere and then, after placing it on my desk, it went right back to sleep. Until today, I hadn’t really investigated the issue, only stealing the occasional cursory glance at the logs and not finding anything obvious. ...
Pihole 6 with Cloudflare DoH
When I started using Pi-hole, I wanted to use an upstream DNS server that supports DoH (DNS-over-HTTPS), like Cloudflare’s DNS servers. As Pi-hole didn’t natively support DoH at the time, my solution was to bake cloudflared into the Docker image. cloudflared is a daemon that listens for unencrypted DNS queries and then forwards them encrypted (via DoH) to Cloudflare’s DNS servers. In my Dockerfile, I used pihole/pihole:latest as the base image and then installed cloudflared via the Debian package on top. This meant I had to periodically rebuild my local Pi-hole image, instead of just pulling the latest version from Docker Hub. ...
VMware Server: Sound in Alsa
Problem For some time, I had the issue that sound output from VMware Server (version 1.0.X) was no longer working reliably. The typical symptom was that sometimes it worked, and sometimes it didn’t. The root of the problem is that VMware Server handles audio output using the Open Sound System (OSS), which has long been replaced in most Linux distributions by the Advanced Linux Sound Architecture (ALSA). Whenever VMware Server tries to output sound for a guest system, it attempts to get exclusive access to the OSS device /dev/dsp—which fails if another application already has exclusive access to it. ...
Sony Ericsson K800i and IMAP Idle
Motivation This short how-to is aimed at anyone who owns a Sony Ericsson K800i (or similar models) and would like to use it as a push mail client. Push mail means that the client (in this case, the phone) receives a notification from the server as soon as new messages are available for the client. This way, you are immediately informed of new emails and don’t have to check manually or at intervals. ...
Awstats Create Stats Statically
Motivation The log file analysis tool AWStats is excellent for evaluating a wide range of logs, particularly access logs from a web server. Normally, statistics are made available directly by AWStats as a CGI script. However, if you find that too insecure (since direct access to the CGI script is required), or if performance is important (e.g., when many customers want to access their stats at the same time), you can also generate the statistics via a cron job and serve them statically. ...
Setting up an SSL VHost under Apache 2
Preface In many cases, using SSL makes sense—such as for accessing internal admin pages like phpMyAdmin. For these purposes, there’s no need to purchase an expensive SSL certificate; you can simply create your own. However, for services like customer logins, it’s better to use an encrypted connection. In this case, a paid certificate is advisable, as users could be scared off by confusing warning messages otherwise. The following guide explains how to configure Apache2 with multiple virtual hosts to additionally provide an encrypted VHost. ...
Virtualizing OpenSUSE 10.3 under Xen on a Hetzner Root Server
Motivation Hetzner has been offering an additional IP subnet with their root servers for some time now, which is included in the price. This makes it possible to run multiple virtual instances on a physical root server without any additional cost. For the virtualization software needed for this, you have free choice (as long as it is supported by the operating system), but there are significant differences in performance and price. Therefore, almost only Xen and OpenVZ are suitable for (semi-)professional use. However, the latter is unsuitable if different operating systems are to be used in the guests (like BSD). Therefore, the choice ultimately fell on Xen. ...
Animated Typo3 TMENU using Mootools
Foreword To create a dynamic menu in Typo3 that works reliably even when Javascript is switched off, I’ve decided on a combination of TMENU and Mootools’s slide plugin. Since it took me a while to implement, I’ll publish it here. Maybe it’ll save someone a little time. Some notes about my configuration: I decided on a 2-level menu (my main menu on the left side), where the first level is used both for navigation (direct click on the link) and for opening and closing the submenu (clicking next to the link). As some people might find it unusual, I installed an additional function that leaves the top menu of the current page open, so people can jump to other pages in the same category. ...