My tips and tricks for passing the AZ-400 Designing and Implementing Microsoft DevOps Solutions exam

I passed the AZ-400: Designing and Implementing Microsoft DevOps Solutions exam in September 2024 and I would like to share some important tips before you take the exam.

General information

• I booked the Microsoft Exam Replay: MCP exam + Retake from Mindhub for peace of mind. In the end, I did not need to retake exam and passed on the first try.
• The online exam lasted 120 minutes and consisted of 54 questions. There were 38 multiple-choice questions, 6 case study questions, and the last 10 questions were in the form of a lab. I used the entire time available and had time to review questions I wasn’t 100% sure about.
• I found the multiple-choice and case study questions of moderate difficulty. They were easier to understand compared to the questions of the AZ-204, as I describe in my other study guide here.
• Be 100% focused while reading the questions. Do not skim the text; read it carefully from top to bottom. Most questions had no vague interpretation.
• While taking the exam I used the link to Microsoft Learn provided in the onVUE application. The browser has no URL input field, and external links on the Microsoft Learn webpages do not work. You can use the search bar to type in keywords and search through the resulting pages.
• The Ctrl+F browser shortcut to search within the contents of the Microsoft Learn webpages is deactivated.. Try not to lose time skimming through the article, since you are going to lose valuable time. Instead try the following advice:
  • Use keywords from a question you are unsure about and try to get information from the search results page.
  • You can use a widescreen and split it in half. On one side, place the onVUE application with the questions, and on the other side, the Microsoft Learn webpage you opened via the onVUE application. This procedure is also shown in the video (click on the Launch the Sandbox button in AZ-204 page) from Microsoft when taking the demo exam.
  • Do not try to search for every question in Microsoft Learn; there is not enough time for that. My approach was to click on the Review Later checkbox for questions I wasn’t 100% sure about and then use Microsoft Learn just for these questions.

Topics to focus on

I did self-directed studying, so the following advice is based on that. You may get different types of questions, so be prepared to study more content than the resources I provide below.

• I strongly advice you against using any question dumps. As you are going to read in the next bullet points basic experience of the Azure DevOps functionality, Git, YAML and Bicep commands and elements will give you a huge boost during the exam! Apart from that, take every new certification as a cool way to to deep-dive into the topics and refresh your practical experience. The goal should be to learn the content to pass the exam, not just to pass the exam.
• I completed the whole DevOps Engineer 30-day plan and I must admit that the content there gives a fantastic preparation for the final exam.
• While doing the 30-day plan you will have, or better said, can practice with some labs. I advice you to complete them all, while redoing every described step in Azure DevOps. Do not skip this part!
• While going through the modules, I took compact notes in OneNote, which helped me sum up the content before the exam. My notes can be summarized in the following important topics to focus on, however, this list does not cover the whole content:
  • Azure DevOps
    • Have a strong understanding of the following terms and hands-on experience on how to create them from the Azure DevOps UI.
      • New projects
      • Dashboards
      • Wiki & Mermaid diagrams
      • Team Board
      • Repositories
      • Pull Requests page & Policies
      • Advances Security
      • Pipelines
      • Environments
      • Releases & Release Gates
      • Task Groups
      • Artifacts
      • Organization settings
      • Project settings
    • Be able to create it and administrate each of the previous elements.
  • Shift-left strategy
    • Know about the different types of automated testing.
  • Continuous Delivery and Continuous Deployment.
    • Know the difference.
  • Microsoft-hosted agents VS. self-hosted agents
    • Know the differences.
  • YAML in GitHub Actions.
    • Have a basic understanding of a YAML file.
    • Be familiar with keywords jobs, steps, on, etc.
    • Know in which folder in our repository we store the YAML files.
  • YAML in Azure DevOps
    • Have a more than basic understanding of a YAML file.
    • Know how a pipeline is structured: trigger, stages, jobs, steps, resources, strategy, template, pool, etc.
    • Know what a parallel job is.
    • Know the difference between a Release Pipeline and a Multi-stage Pipeline.
  • Observability times
    • Be confident about the definitions and know when we use them and what they measure.
    • Mean time to resolution (MTTR)
    • Mean time to recover
    • Time to detect (TTD)
    • Time to mitigate (TTM)
    • Time to remediate (TTR)
    • Cycle time
    • Lead time
  • Branching strategies
    • Know the types and how they differentiate from each other
      • Trunk-based development
      • Feature branch workflow
      • Release branch workflow
      • GitHub flow
      • Fork workflow
  • Branch merging restrictions
    • Have hands-on experience with administrating the Azure DevOps and GitHub restrictions.
  • Tools for large Git repositories
    • Know how they can help you and how they work in the background.
  • Git commands
    • Know a bit more than the basics about
      • checkout
      • branch
      • clone
      • pull
      • fetch
      • push
      • revert
      • upstream
      • log
      • rebase
      • tag
  • Azure Monitor and Application Insights
    • Know the basics
  • Kusto query language.
    • Have good experience. You can use an Application Insights instance in Azure for running some basic queries.
  • Notifications and Teams
    • Know the basics about notifications and how to pass messages to Teams.
  • DevSecOps
    • Have a solid understanding. Know at what stage in the CI/CD process we do which automated test.
  • Security scannings in GitHub and Azure DevOps
  • Have hands-on experience with administrating the different types
    • Secret scanning
    • Code scanning
    • CodeQL
    • Dependabot
  • Service connections in Azure DevOps
    • Know how to create a new service connection and the differences between service principals and managed identities.
  • Deployment strategies
    • Know the theory behind
      • Blue/green deployments
      • Canary releases
      • dark launching
      • A/B testing
      • Progressive exposure
      • Feature flags
  • Azure Traffic Manager
    • Know the different options to distribute web traffic
  • Personal Access Token (PAT)
    • Know how to create a new PAT.
  • Azure Resource Manager (ARM) files
    • Have some hands-on experience with creating simple ARM files.
  • Bicep files
    • Know how to deploy them on Azure by using a YAML pipeline.
  • Azure CLI commands
    • Have good hands-on experience. The very minimum should be creating new Resource Groups, App Services, Storage Accounts and Key Vaults.
  • Desired State Configuration (DSC)
    • Have a good understanding of the theory.
    • Experiment with creating basic Windows PowerShell Desired State Configuration files. Configuration, Node and Resource blocks.
  • Package feeds and upstream sources
    • Read the theory behind them. Know their advantages and know how to create a new feed. Know the most common feed for each programming language and also the roles for using and uploading packages to Azure Artifacts.
  • Versioning
    • Know the basics and the major.minor.patch semantic schema.
• Go through all the Lab exercises and apply the steps in your own Azure DevOps or GitHub subscription.
• Pass the Practice Assessment multiple times. I started with some failed attempts and finished with 5 passed attempts before taking the official exam. Do not try to memorize the answers; understand the reasons behind each answer.
• I did not pay for any video resources available online. I think the content covered in the official Microsoft documentation suffices to pass the exam.

I hope this guide gives you a direction for your studies. I consider the certification an absolute must-have for people working with Microsoft technologies and want to deepen to the DevOps principles.