Slow Down

February 15, 2018 - 1 min read

Anyone who knows me knows I’m quite stubborn. Whenever I set my sights on something I finish it. The last couple of years I’ve been quite busy on GitHub, making at least one commit per day. I’ve had a lot of things I’ve wanted to do and complete, and this commit regimen has kept me on track to do just that. However, nothing comes for free, and although I’ve achieved my goals, I’ve also had to make a lot of sacrifices.

Multicast routing with PIM-SM over GRE

January 23, 2018 - 8 mins read

GRE tunnels are useful in many ways. This blog post shows how to set up multicast routing with pimd over a GRE tunnel. To achieve this we will also set up OSPF over GRE with Quagga, because PIM, unlike DVMRP (mrouted), require unicast routing rules to be established.

       .----{ Intranet }----.
      /    192.168.1.0/24    \
     /                        \
.10 /                          \.20
.--'---. .1  GRE Tunnel  .2 .---`--.
|      |====================|      |
|  R1  |   172.16.16.0/30   |  R2  |
|      |                    |      |
'--.---'                    '------'
   | .1                        | .1 
   |    10.0.1.0/24            |    10.0.2.0/24
   | .2                        | .2 
.--'---.                    .--'---.
|      |                    |      |
|  C1  |                    |  C2  |
|      |                    |      |
'------'                    '------'

In this post we are using the home WiFi network, 192.168.1.0/24, to hook up the GRE tunnel. It is just as easy to extend this to a big corporate Intranet with more routers between R1 and R2. As long as that IT department takes care of the unicast routing between R1 and R2 so that the GRE tunnel can be established.

Threads vs Event Loop, Again ...

September 19, 2017 - 2 mins read

I still get asked this, from time to time. Maybe it’s because I only use event loops, maybe it’s because I’ve written libuEv, or maybe people still don’t understand:

Why an event loop, why not use threads?

So here’s my response, once more.

Packaging Software with Docker

September 17, 2017 - 2 mins read

This post details how to package and deploy software with Docker. The example uses Merecat httpd on Alpine Linux. Try it out with:

docker pull troglobit/merecat

See https://hub.docker.com/r/troglobit/merecat/ for details on how to run Merecat httpd in production.

Install X-Window in Alpine Linux

September 10, 2017 - 2 mins read

How to install LXDM + XFCE4 in Alpine Linux 3.6 when testing with Finit.

Boot Alpine Linux with GRUB

September 9, 2017 - 1 min read

It’s fairly easy to replace the slightly unfriendly syslinux with grub (grub2) in Alpine Linux. I use v3.6 but YMMV.

GIT, Autoconf and Automake in OpenBSD

June 6, 2017 - 1 min read

Reminder to self: echo "https://ftp.eu.openbsd.org/pub/OpenBSD/" >/etc/installurl pkg_add git autoconf automake libtool Select the latest versions, then add the following to ~/.profile: AUTOCONF_VERSION=2.69 AUTOMAKE_VERSION=1.15 export AUTOCONF_VERSION AUTOMAKE_VERSION With your selected versions, of course.

HTTPS proxy for Merecat httpd

February 12, 2017 - 2 mins read

This is a HTTPS proxy HowTo for Merecat httpd using pound and OpenSSL. Pound is a reverse proxy, load balancer, and HTTPS front-end for Web servers. It is available in Debian/Ubuntu and is very simple to set up: First install the package, including OpenSSL, or LibreSSL: sudo apt install pound openssl Use OpenSSL to create a self-signed certificate: mkdir ~/certs cd ~/certs openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.

Emulate an actual MTD device in Qemu

February 2, 2017 - 4 mins read

Having worked with Linux for the last 20 years, and embedded for more than ten of them, I’ve become quite a fan of virtualization in general and Qemu in particular.

Qemu is a fantastic little tool, created by the Open Source superhero Fabrice Bellard. It can be used to verify an embedded system without having to deal with the problems of actual HW until you really have to. Don’t get me wrong, HW excites me like any other nerd, but if the HW is new and shaky it can be quite a pain to develop higher level functions.

My holy grail is to have a 100% complete and accurate virtualization target per architecture to test my various software projects on. That’s why I created TroglOS.

Wolfenstein-3D on RetroPie

January 15, 2017 - 2 mins read

The last game I ever played was Castle Wolfenstein 3D, released in 1992 for MS-DOS, made by the now legendary id Software. OK, admittedly I’ve played other games since then, but I’ve never again been so manic about a game since Wolfenstein.

This post is about how to build, install and set up Wolfenstein 3D on a Raspberry Pi running RetroPie … on a Picade :-)