DEV Community: Jerome S

DNS Validation using AWS Certificate Manager (ACM) and Porkbun

Jerome S — Wed, 28 May 2025 15:21:27 +0000

tldr;

I found out I was adding the wrong details in Porkbun. The most crucial part was not including the trailing dot and using the correct host in the Porkbun CNAME record.

Adding A New Resume Website

I recently decided that I wanted to create a copy of my resume website on AWS just for practice.

I planned for the AWS website to be accessible via aws.jeromes.dev, and to make that happen I used:

AWS S3 to host the files
AWS CloudFront for the CDN
AWS Certificate Manager (ACM) to manage SSL certificates

I'm already using Porkbun as my DNS provider and domain registrar. Their UI is pretty straightforward, so I figured adding a subdomain would be too.

Steps To Add a Subdomain

I won’t dive too deep into each step, but here’s the high-level plan I went with:

Upload the files to AWS S3
Create a Distribution in AWS CloudFront for my desired subdomain
Request a certificate for the new subdomain in ACM
Add a new CNAME DNS record in Porkbun
Wait for ACM to validate my certificate
Finalize the CloudFront distribution setup using the issued cert
Review everything and complete the setup

Since I’m using a custom DNS provider, I followed AWS’s guide for DNS validation.

Not too difficult, right? Everything seemed laid out clearly. But then I got stuck for an hour trying to get step 5 to work!

Where Did I Go Wrong?

After a few attempts, why wouldn’t ACM validate my certificate?!

Turns out, Porkbun does some things automatically behind the scenes.

Specifically, when adding the CNAME value, you’re not supposed to add the trailing dot (.) character!

Rookie mistake? Definitely. After all, all I ever did before was update nameservers or just create A Records. This was my first time creating a subdomain with a validation record.

Oh well, live and learn. At least I got it working—and you can now visit my new AWS-hosted resume site at aws.jeromes.dev.

Hopefully this helps someone else stuck in the same situation.

Some tips for beginners trying to take the AWS Cloud Practitioner certification :)

Jerome S — Mon, 19 May 2025 04:09:06 +0000

Jerome S

May 19 '25

Passing the AWS CLF-C02 Certification [AWS Cloud Practitioner Blog]

#aws #certification #continuouslearning #cloudcomputing

Comments 28

4 min read

Passing the AWS CLF-C02 Certification [AWS Cloud Practitioner Blog]

Jerome S — Mon, 19 May 2025 04:02:28 +0000

tldr;

I passed! It took me 2 weeks to study, and I’m sharing my thoughts.

Allot 1–2 hours of study time every day leading up to the exam, and take practice exams to gauge your understanding and reinforce weak areas.

Update: 28 May 2025

Some guides will encourage using "certified dumps". I am against it as this is a form of cheating by memorizing instead of truly understanding concepts.

My Updates

I've written in my previous post that I had to scratch the itch and dive back into AWS.

Since then, I’ve studied and passed the certification. Now I can brag on my LinkedIn profile about my shiny new certificate.

Of course, I also immediately added it to my resume website!

Do I really need this certificate?

Actually, no.

To be honest, it’s always still best to have real-world experience over a certificate. However, certificates are a way to show that you know what you’re doing (or about to do), and studying for one puts you in a kind of “performance space” where you’re forced to make sure you know your stuff when it counts.

"Realistic" Preparation Timeframe

I came from a technical background, had some previous experience using AWS, and had attended a few trainings in the past.

If I were to estimate how much time you'd need, I'd say:

1–2 months if you are not coming from a technical background and have not used AWS.
2–4 weeks if you come from a technical background but are not familiar with AWS or cloud concepts.
1–2 weeks if you're already familiar with cloud concepts and have a technical background.

How did I come up with these?

Well, they’re based on my personal learning speed and experience—but I believe anyone who’s motivated could achieve similar results in roughly the same timeframe.

Study Time

Like I mentioned before, I’m a family guy with a 9-to-5 job. I only had time to study in the evenings and on weekends.

Here’s what my study week looked like:

1–2 hours of focused study on weekdays
6–8 hours of study on the weekends

Given my background, this was enough—but I encourage those with less AWS experience to put in more hours to gain mastery.

Study Materials

Here are the three main resources I used:

1. AWS Skill Builder – AWS Cloud Practitioner Essentials

This course, provided by AWS, is free. It’s a 7-hour digital training that I’d recommend for someone not familiar with AWS or someone who wants to refresh their knowledge.

They use a lot of metaphors and relatable examples to explain cloud concepts, which is super helpful for beginners.

2. ExamPro – AWS Certified Cloud Practitioner (CLF-C02)

Reddit came through again—this course is one of the most recommended out there, and for good reason.

It’s packed with information. While the full version is paid, there’s a free version that gives you access to all the video content (just not the flash cards or mini quizzes).

Some videos include “follow-alongs,” where Andrew shows you how things are done in the AWS console. That really helps map your learnings to actual usage.

⚠️ Heads-up: This course is info-dense. I suggest you take #1 first before diving into this one—it helps to get the cloud basics down before tackling the heavier stuff.

Also, this course aligns well with the AWS CLF-C02 Exam Guide, which outlines the exam topics and gives some useful study strategies.

3. AWS Skill Builder – Cloud Essentials Knowledge Badge Assessment

This quiz is a 50-item test to gauge your AWS knowledge. I used it to figure out what areas I was weak in and to get used to the testing format.

Plus, you get a little badge after completing it. Who doesn’t love badges?

4. ExamPro – AWS Certified Cloud Practitioner (CLF-C02) Free Practice Exam

Another gem from ExamPro—this 65-question sample test is very close to the actual certification exam format.

You can flag questions, review them, and even comment.

The real benefit here is getting used to scenario-style questions and thinking like an AWS Cloud professional.

5. Quizlet – AWS Certified Cloud Practitioner CLF-C02 Flash Cards

These flash cards helped me recall important concepts—especially useful for a quick refresher on exam day.

Basically, just allot 2 hours of focused study per day and keep at it until you feel confident.

I strongly recommend taking practice exams and aiming for a 90%+ score before scheduling your AWS Certification exam.

Good luck on your journey!

Rekindling lost AWS knowledge [AWS Cloud Practitioner Blog]

Jerome S — Thu, 01 May 2025 06:15:58 +0000

tldr;

I'm just a regular guy trying to balance work and life while aiming for an AWS Cloud Practitioner certificate.

How I got here

I came across the Cloud Resume Challenge, and one of the suggestions there was to document the journey—so I decided to give dev blogging a try.

Even though I already have my resume up at my own resume website, I figured—why not try to redo it on AWS?

Right now, my website is built with simple React.js and hosted on Vercel. It was easy to set up and already serves as my current resume website. But then I thought—what's stopping me from rebuilding it in AWS? There's no rule or law that prevents me! So, why not?

My previous AWS experience

In my previous job, I was in charge of groups of developers. Aside from managing people, I also handled the tech—and most of it was hosted in AWS.

Despite the small and limited scope, I was able to get hands-on with AWS tools that were given to me so that (1) we could observe the infrastructure, (2) suggest improvements to it, and (3) better understand it for future application architecture work.

AWS Knowledge Stagnation

Over the past few months, I’ve had the itch to dive back into AWS, but of course, the motivation didn’t really come—mainly because I don’t use it at all in my current work, and, let’s be honest, it can cost money.

But hey, sometimes you gotta lose some (money) to gain some (knowledge). It’s just a small spend anyway—I'm just being stingy. Sure, I could do this on other platforms for free, but in my opinion, AWS is still a great tool to learn—especially since I get most excited when I’m working on application migrations.

What can you expect should you choose to follow this series

I know there are a ton of other series out there that guide you through learning AWS from scratch. If you're looking for a fast track, those are probably your best bet.

I’m coming from the perspective of a "seasoned" developer who has other interests outside of programming. I recently moved to a foreign country and am learning a new language, while also living with my wife—whom I love deeply and want to spend as much quality time with as possible. I also want to keep an active lifestyle by going to the gym and hitting the trails.

Basically, I'm just a regular family guy trying to stick to my principles of continuous learning, physical fitness, and enjoying life as it comes. I won’t go deep with full guides, but I’ll drop quick tips that cover 80% of real-world scenarios.

I hope you enjoy reading my blog about my AWS journey—as a regular guy.