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Practical DevSecOps CTMP course and exam

2023-01-16 07:20:00

In early 2021 I needed to learn about DevSecOps and CI/CD and I needed it fast. A crash course if you will, into all things automation, pipelines, SAST, SCA, DAST and more. I went with PDSO's Certified DevSecOps Professional course, which included a 12h hands-on exam.

Here's my review from back then, TLDR: I learned a huge amount, their labs were great, their videos are good, their PDF was really not to my liking. 

Since then I've worked with a great team of people, team Strongbow at ${Bank}, and we've taught over a thousand engineers about PKI, about pentesting, about API security and about threat modelling. So when PDSO introduced their CTMP course (Certified Threat Modelling Professional) I jumped at the chance to formalize my understanding of the topic.

My review of the training materials is going to be very similar to that of CDP:

I took the exam yesterday and it was great, better than I expected!

For anyone looking for tips to take the CTMP exam: tags: , ,

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An actual office for Unixerius

2023-01-08 19:58:00

Before and after redecoration

Way back when, over ten years ago, Dick had rented some local office space for Unixerius. He used it for storage, I don't think anyone ever did some actual work over there. So, that rental space wasn't long-lived.

After Dick's passing in 2021, I took over running Unixerius in January of 2022. One practical hitch about owning a company which I didn't care for, is having my private home address in the chamber of commerce's registry. That's why I rented a flex-desk at the now defunct Data Center Almere

Per the start of 2023 I'm now renting an actual office space again, at MAC3Park. They gave me a good deal on a 25m2 room, with eletricity and Internet-access included. And because the previous tenant had left in a hurry there was even some furniture left behind! They were going to toss it all, but I was very happy to have a big desk, decent chair and a comfy sofa!

The only downside to the room was the awfully bad paintjob a previous tenant had done. Dreary grey, with streaks, splotches, grease marks and overspray. I spent the week between Christmas and New Year's redecorating and cleaning. It's now a very, very comfortable office for work and studying!

The Ikea book case used to be in my kid's room and now holds memorabilia to past jobs, teams, colleagues and students. tags: ,

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Microsoft Natural Ergonomic 4000 keyboard: fixing non-functional key

2023-01-06 19:43:00

Keyboard membranes

I've been using Microsoft's ergonomic keyboards for close to twenty years now. I've had Comfort Curve models and Natural Ergonomic ones. The Natural Ergonomic 4000 has been my daily driver at the office for years. 

I hated it when it broke down. Or... When literally one of the keys broke down. Every single key on the keyboard worked fine, except the letter "c". It just wouldn't go. Nada. 

Thanks to user teevothis's disassembly video on YouTube, I found the four two screws I never managed to find before.

Opening her up, yes there were quite some crumbs and dust. But nothing overtly wrong. Pressing contacts on the membranes directly worked as expected, but the "c" also didn't work this way. A quick visual check of the contacts for the "c" showed no damage, nor debris interfering with the contact.

Visual inspections of the traces leading to the "c" also didn't show any clear damage.  It did show that the "c" key is at the end of a specific series of contacts, which explains why it's the only key on the whole keyboard that's malfunctioning: something is interfering with its individual trace(s).

There were a few splotches of brown on the keyboard membranes, which suggests I at one point spilled cola in my keyboard. So, I did something scary: I disassembled the actual membranes, which separate into three layers of plastic. There's the bottom layer with traces on top, a middle insulating layer and the top with traces on both sides of the plastic. 

To take the membranes apart, there are four places where the plastic was melted together which you need to carefully destroy. :D A scalpel will do fine, as long as you're very careful. 

I cleaned all three layers, on both sides each, and let'm dry. Putting things together bit by bit: Halleluyah! It worked again!

My hypothesis: some spillage from the cola had gotten into one of the layers of the membrane, shorting the trace for the "c" to its neighbor. Oddly, its neighbor wasn't affected. tags: ,

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