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Practicing with azcli, to build an Azure DevOps lab

2022-07-09 20:52:00

This fall I am scheduled to teach an introductory class on DevSecOps, to my Linux+ students at ITVitae. Ideally, if things work out, this will be a class that I'll teach more frequently! It's not just the cyber-security students who need to learn about DevSecOps, it's just as important (if not more) to the developers and data scientists!

Since this course is going to be hands-on, I'm prepping the tooling to configure a lab environment with students forming small teams of 2-4. I'd hate to manually set up all the Azure DevOps and Azure Portal resources for each group! So, I'm experimenting with azcli, the Azure management command line tool. 

Sure, I could probably work even more efficient with Terraform or ARM templates, but I don't have time enough on my hands to learn those from scratch. azcli is close enough to what I know already (shell scripting and JSON parsing), to get the show on the road. 

Here's a fun thing that I've learned: every time one of my commands fails, I need to go back and make sure that I didn't forget to stipulate the organization name. :D 

For example:

% az devops security group membership add --group-id "vssgp.Uy0xLTktMT....NDk0" --member-id "aad.ODU0MjMyZTAtN...0MmVk"

Value cannot be null.

Parameter name: memberDescriptor

That command was supposed to add one of the student accounts from the external AD, to one of the Azure DevOps teams I'd defined. But it keeps saying that I've left the --member-id as an empty value (which I clearly haven't).

Mulling it over and scrolling through the output for --verbose --debug, I just realized: "Wait, I have to add --org to all the previous commands! I'm forgetting it here!". 

And presto:

az devops security group membership add --group-id "vssgp.Uy0xLTktMT....NDk0" --member-id "aad.ODU0MjMyZTAtN...0MmVk" --org ""

That was it! tags: , ,

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More beta exams! ISC2 ELCC and CompTIA Linux+ 005

2022-06-29 21:28:00

At the end of 2021 I took the beta version of Comptia's XK0-005, which went live earlier this month as XK1-005. My opinions on the exam still stand: it's a solid exam with a good set of objectives. And luckily I passed. :D

Yesterday, I took part in another beta / pilot: (ISC)2's ELCC, also known as their Entry Level Cybersecurity Certification. I didn't take it to pad my own resumé, I did it to see if ELCC will make a good addition to my student's learning path. So far they've been using Microsoft's MTA Security (which is going away).

(ISC)2, most famously known for their CISSP certification, saw an opportunity in the market for an entry level security certificate. Some would call it a moneygrab... But the outcome of it, is their ELCC.

Looking at the ELCC exam objectives I have to say I like the overall curriculum: the body of knowledge covers most of the enterprise-level infosec knowledge any starter in infosec would need to know. It's very light on the technical stuff and focuses mostly on the business side, which I think is very important!

I've heard less-than-flattering reviews of (ISC)2's online training materials, meaning that I'd steer students to another source. And, having taken the exam, I have to admit that I think it's weak. 

Maybe it's because this was a beta exam, but a few topics kept on popping up in questions with the same question and expected-answer being given in slightly different wordings. With 100 questions on the test, I was expecting a bit more diversity. 

I also feel that a lot of the questions were about dry regurgitation: you learn definitions and when provided a description, you pick the right term from A, B, C or D. CompTIA's exams take a very different approach, where you're offered situations and varying approaches/solutions to choose from. 

Overall take-aways regarding ISC's entry-level cybersecurity certification: tags: , ,

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Nostalgia: VMEbus and OS-9

2022-06-15 06:35:55

Recently I've been thinking back about old computing gear I used to own, or worked on in college. Nostalgia has a tendency to tint things rose, but that's okay. I get pangs of regret for getting rid of all my "antiques" (like the Televideo vt100 terminal, the 8088 IBM clone, my first own computer the Pressario CDS524) but to paraphrase the meme: "Ain't nobody got room fo' all that!"

Still, it was really cool to run RedHat 5 on the Compaq and having the Televideo hang off COM1 to act as extra screen and keyboard.

Anyway... that blog post I linked to, regarding RH5, also mentions OS-9. OS-9 was (is, thanks to NitrOS9). It was an OS ahead of its time, with true multi-user and multi-processing, with realtime processing all on at the time relatively affordable hardware. It had MacOS and Windows beat by at least a decade and Linux was but a glint in the eyes of the future.

I've been doing some learning! In that linked blog post I referred to a non-descript orange "server". Turns out, that's the wrong word to use!

In reality that was a VMEbus "crate" (probably 6U) with space for about 8-10 boards. Yes it used Arcnet to communicate with our workstations, but those also turn out to be VMEbus "crates", but more like development boxen with room for 1-2 boards in a desktop box.

Looking at pictures on the web, it's very likely that the lab ran OS-9 on MVME147 boards that were in each of the crates.

Color me surprised to learn that VMEbus and its successors are still very much in active use, in places like CERN but also in the military! But also in big medical gear, like this teardown of an Afga X-Ray machine shows.

Cool stuff! Now I wanna play with an MC68k box again. :) tags: , , ,

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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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