Valentine’s blog

My personal blog about tech and other hobbies
Oosterscheldekering

Travelin' The Netherlands

This post serves as the support page for my book “Travelin’ The Netherlands”. Here you can find additional downloads and links. You can buy the book at the following places: Kobo eBooks LeanPub Amazon Kindle Apple Books Route download Click here to download the GPX file with the full route. Photos High resolution versions of the photos in the book can be found here (in order of appearance): Oosterscheldekering Ring-tailed lemur Looming weather Highlander Cupola Valkenburg Boar Dunes Multitool Blade Comparison Multitools Knives View from the Plompe Tower Flashlights Contact Multiple contact options are listed on the home page. ...

June 1, 2025 · 1 min · 99 words · Valentijn Harmers
system management

Trip planning with Garmin

Need to go somewhere? The first thing most people do is getting out their phone and punch in the destination address into something like Google Maps. You get step-by-step driving directions and can even view the destination in Google Streetview to get some impression of what to expect once you get there. I still remember the time when my dad bought our first car navigation system. It was a “TomTom” which was manufactured by a Dutch company with the same name. This little device brought us much joy and saved us a lot of trouble by taking us directly where we needed to be. I still remember when it instructed us to take a ferry while we were on vacation. This might not seem so special at first hand, but as a young boy, it felt epic. ...

May 27, 2024 · 28 min · 5895 words · Valentijn Harmers
system management

The OpSec Series - System Management

This post is part of a larger series. You can find all posts over here. Setting up systems can be a lengthy and boring process. It is easy to forget a step, execute it in the wrong order or use the wrong settings. I still remember the day when I had to reinstall the Operating System of my laptop on a yearly basis. Microsoft Windows has a tendency to become slower over time. Installing all kinds of software like games and Integrated Development Environments (IDEs) such as Visual Studio and Netbeans also didn’t help. Cleaning tools like CCleaner and Smart Defrag only got you so far. Sometimes the only thing left to do was to reinstall the OS and start fresh. ...

January 22, 2024 · 20 min · 4107 words · Valentijn Harmers
authentication

The OpSec Series - Authentication

This post is part of a larger series. You can find all posts over here. We have arrived at one of the most hated parts of security: Authentication. Everyone knows the frustration of having to type in a username and password before accessing the systems you need to do your work. You even need specialized applications in order to keep track of all of these credentials. I sometimes feel like a stamp collector but instead of collecting stamps, I am collecting passwords. ...

March 14, 2023 · 19 min · 4025 words · Valentijn Harmers
chat

The OpSec blog series - Chat platforms

This post is part of a larger series. You can find all posts over here. Hello and welcome to a new blog post in the OpSec blog series. As already mentioned in the previous post, this one will be about chat platforms. I can still remember a time when I was in school and carried around a Sony Ericsson J110 dumb phone. I didn’t use it much. It was just for contacting my parents in case of emergencies. All the cool kids in my class had these BlackBerry devices and they used an application called BlackBerry Messenger (BBM) to send messages to each other. I was told that it was cheaper to use BBM than to send messages over SMS. ...

October 1, 2022 · 37 min · 7768 words · Valentijn Harmers
e-mail

The OpSec blog series - E-mail encryption

This post is part of a larger series. You can find all posts over here. Welcome to the second blog post in this blogging series. I recommend reading the introduction post before starting with this one. Email is one of the oldest ways to communicate on the world wide web. And since the internet was created with openness in mind, so it shouldn’t come as a surprise that e-mail wasn’t designed to be very secure. Sending an e-mail is like sending a postcard. Every party involved in the delivery process can read the contents of the message. From the people working in the distribution centers to the mailman who delivers the card to your door. ...

September 13, 2022 · 30 min · 6278 words · Valentijn Harmers
Beach

Creating a digital life raft

Over the span of our lives, we accumulate a lot of stuff. Some of this stuff is precious to us so we keep it in a secure place like a safe or strongbox. Some of this precious stuff can also be digital and therefore must be secured into digital strongboxes and safes but what happens when you lose the key? When your work in IT, you have a minimum of two employers: the company you work for and your family. I am the designated IT support and data custodian at home. It’s my job to keep all family pictures and other important files complete and available. And after going through the experience of losing my pictures of our vacation trip to Paris years ago, I am next to paranoid when it comes to making backups. ...

September 9, 2022 · 4 min · 750 words · Valentijn Harmers

The OpSec blog series - Introduction

Have you ever had the desire to improve the security of your systems but had no idea how to do it? You might have read all kinds of articles on the web about hacked companies that needed to pay large sums of money to get access to their data again. But what can you do, when you are just a system administrator of a small company with a non-existent security budget? Well, you can start reading the OpSec blog series in order to acquire the knowledge you need to make your environment more secure and give hackers a hard time. ...

September 7, 2022 · 11 min · 2221 words · Valentijn Harmers

My working environment throughout the years

As someone who works in the IT sector and does all kinds of tech stuff in his free time, having a proper working environment is of the utmost importance. The term “Working environment” is a broad term with can be anything from the people you work with to the desk you sit at, but I am focusing on the thing I spend my time looking at for most of the day. ...

September 2, 2022 · 20 min · 4250 words · Valentijn Harmers

Passwordless LUKS setup with Clevis

Typing your password at every system bootup might get you annoyed at times. Especially when you are used to Windows and macOS systems which store the disk decryption password in the TPM. But what if I told you that you can also achieve this on your Linux setup. We can use an application called ‘Clevis’ to get the job done. I will describe the installation and configuration steps for Ubuntu and Fedora, but the steps should be about the same for other Linux distro’s. ...

August 2, 2022 · 2 min · 267 words · Valentijn Harmers