Scenario: A new Linux box has been installed with Vagrant, and now I must git clone a non-open repository to the server, so I need to forward my SSH keys to the root user on the virtual server. 1) Add the following line to your Vagrantfile: config.ssh.forward_agent = true 2) Once you’ve “vagrant ssh”‘d to… Continue reading Forwarding SSH keys to a Vagrant box
Author: amplifier
A method for neatly stowing the lines on a skydiving parachute
Looking at the way some freshly licenced (and some older) jumpers struggle with making neat line stows, I figured I’d document the method I’ve been using to stow my lines. Here goes: A method for neatly stowing lines These instructions are for stowing a bight of lines on the right-hand side of the bag; for… Continue reading A method for neatly stowing the lines on a skydiving parachute
My “first order retrievability” toolbox
Here’s my take on a toolbox observing the principle of “first order retrievability” as popularized by Adam Savage. In short, all tools can be reached without moving other tools out of the way first. The box itself is a Draper 48566 with the trays removed. The insert for the tools is built from foamcore to… Continue reading My “first order retrievability” toolbox
Filtering out outliers in Arduino ultrasonic distance sensor data
A friend of mine asked me how he could remove invalid data points from the measurements made by the ultrasonic range finder in his Arduino project. A quick search got me to this page, but some of the links were dead and there was no complete example on the page anyway, so I decided to… Continue reading Filtering out outliers in Arduino ultrasonic distance sensor data
Amount of content in The Lord of the Rings vs. The Hobbit
While cleaning up my desktop, I stumbled upon a calculation I did after the Hobbit movies came out. What I wanted to find out was how many words in the book would be used for each minute of the movie. Seeing as The Hobbit is a much shorter book than the LOTR trilogy, it would… Continue reading Amount of content in The Lord of the Rings vs. The Hobbit
Making a composite material from ABS slurry
Since I do a fair bit of 3D-printing, there’s always plenty of scrap ABS available. Some of the scraps go into the acetone / ABS slurry that I use to coat the build platform before each print, but there’s still plenty more to go around. So, this got me thinking: “If I make something out… Continue reading Making a composite material from ABS slurry
3D-printed buildings and military units for King of New York
Here’s a project I recently finished: 3-printed buildings and military units for the board game King of New York:
Nginx as origin for S3 with authentication, with CDN on top
We recently had a small problem with our content delivery system. The setup is as follows: – AWS S3 bucket that requires authentication – EC2 instance, running Nginx with ngx_aws_auth – ELB load balancer in front of the EC2 instance – CDN configured to use the ELB as the origin The problem was that the… Continue reading Nginx as origin for S3 with authentication, with CDN on top
Nginx: Reject request if header is not present
It was surprisingly difficult to find a full working example of this, so here’s my take on “How to make Nginx require that a certain header is present with a certain value in the incoming request”: nginx.conf: http { map $http_x_mycustomheader $is_mycustomheader_not_ok { default “1”; MyApprovedValue “0”; } … } mysite.conf: server { … location… Continue reading Nginx: Reject request if header is not present
Obi-Wan Kenobi’s flashlightsaber
I happened to find this 3D-printable model of Obi-Wan Kenobi’s lightsaber, so I decided to see if me and my 3D-printer were up to the task. There’s also an article about designing the lightsaber model in the Ultimaker blog.