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Comparing Linux+ objectives between XK0-004 and XK0-005

2022-05-11 17:43:00

Finally, the CompTIA Linux+ beta embargo has lifted! I can post the comparison I made of the objectives between XK-004 and 005!

In the spreadsheet, you'll see: tags: ,

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Passed the CKA exam

2022-05-08 09:19:00

It's been a very long time in coming, but I finally passed my CKA (Certified Kubernetes Admin) exam yesterday. 

When I say "a long time", I mean that this path of studying started back in August 2021 right after finishing teaching group 41 at IT Vitae. Back then, I started out on the Docker learning path at KodeKloud, to get more familiar with containerization in general. I'd considered going for the DCA exam, but comparing it to CKA I reconsidered and added a lot more studytime to just hop onward to Kubernetes.

I can not say enough positive things about KodeKloud. The team has put a lot of effort into making great educational content, as well as solid lab environments. The cost-value comparison for KodeKloud is excellent! I plan on finishing their DCA content later this year, so I can then turn to RedHat's EX180 (Docker/Podman and OpenShift) exam.

Aside from KodeKloud's training materials, the practice exams at were great. You get two free practice exams as part of your CKA exam voucher and I earned a third run by submitting some bug reports. 

Again, the value for money at is great: in-depth exercises, a stable testing environment and a exam setup that properly prepares you for the online CKA testing environment. 

Finally, the actual exam: registration was an okay process, signing in with the proctor went excellent and the exam itself worked fine as well. I did learn that Linux Foundation are very strict about the name put on your registration. I put in "T.F. Sluijter-Stek" because legally that is my identity, but they actually wanted "${FirstName} ${LastName}" so for me my "${DeadName} ${MaidenName}". Oh well; no biggy. The proctor was very patient while I went and updated my name on the portal. 

So to summarize: tags: , ,

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Windows Server: upgrade from ServerDataCenterEval to ServerStandard

2022-04-18 15:52:00

For those who just want the answer to the question: "How do I upgrade a Windows Server DataCenter Evaluation edition to a licensed Windows Server Standard?", here's where I got my answer. I'll provide a summary at the bottom.


My homelab setup has a handful of Windows Server systems, running Active Directory and my ADCS PKI system. Because the lab was always meant to just mess around and learn, I installed using evaluation versions of Windows Server.

I kept re-arming the trial license every 180 days until it ran out (slmgr /rearm, as per this article). After the max amount of renewals was reached, I re-installed and migrated the systems from Win2012 to Win2019 and continued the strategy of re-arming. 

Per this year, I decided to spring for a Microsoft Partner ActionPack.

Signing up Unixerius for the partnership took a bit of fiddling and quite some patience. Getting the ActionPack itself was a simple as transferring the €400 fee to Microsoft and away I go!

The amount of licenses and resources you get for that money is ridiculously awesome. Among the big stack of coolness, for my homelab, it includes ten Windows Server 2019 and 2022 licenses. There's also great Azure and MS365 resources, which I'm definitely putting to good use; it's a great learning experience!


Upon inspection of my homelab, it turns out that most of my Windows VM were installed as "Windows Server DataCenter Evaluation", simply because I wasn't aware of the difference between the Standard and DataCenter editions. Now I am. :)

It turns out that the ActionPack does not include licenses for DataCenter edition, so I needed to find a way to upgrade from the type "ServerDatacenterEval" to "ServerStandard". This great article helped me get this tricky situation fixed, because it's not completely simple.


  1. Download the official Windows Server 2019 installation ISO from your partner center benefits dashboard.
  2. Make a snapshot or backup of your Windows server. 
  3. Login to the server with your account that has admin rights. 
  4. Start regedit.
    1. Go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion;
    2. Change CompositionEditionID to "ServerStandardEval".
    3. Change EditionID to "ServerStandardEval".
    4. Change ProductName to "Windows Server 2019 Standard".
  5. Close regeditDo not reboot.
  6. Connect the Windows Server installation ISO to the VM (or DVD drive).
  7. Start setup.exe from the DVD.
    1. Follow the installation instructions.
    2. Choose to upgrade "Windows Server 2019 Standard" and opt to use the online patches and updates.
    3. This process should allow you to retain all software, configurations and data.
  8. The whole process of upgrading and installing will take hours.
  9. Upon completion, you will need to provide your license key. Using the Settings app and the activation tool may not work. Turn to the commandline and run: dism /online /set-edition:serverstandard /productkey: /accepteula. tags: ,

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Some struggles are hard to break

2022-02-18 12:27:00

When you next have 15-20 minutes and some coffee/tea/beer/etc, I'd consider this article an interesting read for anyone in DevSecOps and InfoSec.

The Six Dumbest Ideas in Computer Security - Marcus Ranum

That dates back to 2005 and reminds me that "the more things change, the more they stay the same". We still struggle with a lot of these issues today and my team at $Client literally discussed some of these last week.

Is Ranum infallible? No. Is Ranum 100% correct? No, I'm sure he's not. Is point #4 dead wrong? Yes. But it's still a nice read to make you pause and think.

And, while we're traipsing down Memory Lane, here's Schneier in 2004 bringing up product safety standards for software products. tags: ,

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Took the CompTIA Project+ beta

2022-01-29 11:04:00

Back in November, CompTIA announced the upcoming Project+ v5 certification exam. My day-to-day job does not entail project management, but I was curious about the exam anyway.

It's no secret that beta-testing CompTIA exams has become a hobby of mine. Thus, I jumped at the chance to take it, when someone posted about it on Reddit. As has become tradition, I pludged the exam: i.e. I went in with zero preparation, only browsing through the exam objectives document

My impressions of Project+ PK1-005 (to become PK0-005):

Overall, I'm feeling pretty good about this update to Project+. 

Will it be a valuable certificate for your resumé? Maybe not, with bigger brand names having more recognized project management certs. But will it rank up there with something like PSM-I or PSPO-I? Or something like PRINCE2 fundamentals? Yeah, probably. 

Finally, do I think I passed? I expect I didn't: my experience and knowledge of formal project management, especially things like PRINCE2, is very meager. tags: , ,

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VirtualBox and Vagrant error: E_ACCESSDENIED (0x80070005) - Access denied

2022-01-23 09:25:00

I've been using Vagrant for a lot of my quick tests and my classes for a while now. A few weeks ago, my old Vagrantfile configurations stopped working, with Vagrant and Virtualbox throwing errors like these:

There was an error while executing `VBoxManage`, a CLI used by Vagrant for controlling VirtualBox.The command and stderr is shown below.

Command: ["hostonlyif", "ipconfig", "vboxnet0", "--ip", "", "--netmask", ""]

Stderr: VBoxManage: error: Code E_ACCESSDENIED (0x80070005) - Access denied (extended info not available) 

VBoxManage: error: Context: "EnableStaticIPConfig(Bstr(pszIp).raw(), Bstr(pszNetmask).raw())" at line 242 of file VBoxManageHostonly.cpp


Or, in a more recent version of Virtualbox:

The IP address configured for the host-only network is not within the allowed ranges. Please update the address used to be within the allowed ranges and run the command again.



Valid ranges can be modified in the /etc/vbox/networks.conf file.


A search with Google shows that a few versions ago VirtualBox introduced a new security feature: you're now only allowed to whip up NAT networks in specific preconfigured ranges. Source 1. Source 2. Source 3.

The work-arounds are do-able. 

While the prior is more correct, I like the latter since it's a quicker fix for the end-user. 

BEFORE: "private_network", ip: ""


AFTER: "private_network", ip: "", virtualbox__intnet: "08net"



Apparently it's enough to give Virtualbox a new, custom NAT network name. tags: , , ,

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That one time I didn't beta-test two Mile2 exams

2022-01-22 16:00:00

Mile2 are a training company, aiming to provide vendor-neutral InfoSec training and certification exams. I've heard their name a few times, but have never taken any of their trainings. Reddit and TechExams also have little experiences posted about them.

That's why I was very curious and interested to join Mile2's beta program for their C)ISSO and C)PTE exams. These new versions are ANSI accredited (meaning they will require CPE points every three years) and have been renewed in a few other ways. Sounds like a great opportunity to give them a shot. Besides, taking beta exams is a hobby of mine.

Requesting access was a solid process, as you needed to submit a bit of a resumé to prove you'd be a valued reviewer/tester. I was approved for the program pretty swiftly, with clear instructions from their marketing team. 

I reported back to the team, with a few doubts about the sign-up process.

Half an hour later my access was revoked and I was ejected from the beta program, the team citing my "obvious distrust of their organization". Oh well. tags: , ,

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Memes in corporate communications

2021-12-28 07:29:00

It's been years now, since Internet meme imagery has started showing up in corporate communications: from adverts to internal Powerpoint presentations, you've probably seem them. A quick talk at the office made me remember that classic episode of Star Trek:tNG, where the crew have a run-in with the Tamaran who speak in metaphors.

It made me realize, as linguists have been pointing out for aeons apparently, that we as global people can definitely head in the same direction. I mean, sure! My best friend Menno and myself can speak in 90s animation memes! So why not?

Here's how you could explain the current Log4j hullabaloo in meme-speak.

JNDI:       There's no way this could go wrong!
Log4j:      ORLY?
Log4j:      Yo dawg, we heard you like resolvers in your logs! So we put...

2021:       Pwning log4j hypetrain, let's go! To the moon!
Researcher: Shit's on fire yo.
InfoSec:    My hair is on fire! My hair is on fire!
Management: Let's go! In-n-out! 20 minute adventure
InfoSec:    One does not simply ...
DevOps:     Science dog has no idea what he's doing.
DevOps:     I know nothing about ... at this point I'm too afraid to ask
InfoSec:    This is fine.

2031:       Remember when? ... Pepperidge farms remembers! tags: ,

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