AZ-400 Continuous Delivery 5 — Questions and Answers
Question 1: Which approach best supports immutable infrastructure in a continuous delivery pipeline for Azure VMs?
- Run configuration scripts on existing VMs each deployment
- Build a new VM image with Packer and swap it via a scale set rolling update (Correct answer)
- SSH into VMs and pull the latest code manually
- Use Azure Automation DSC to apply configuration drift corrections
Correct answer: Build a new VM image with Packer and swap it via a scale set rolling update
Building new images with Packer and updating scale sets treats infrastructure as immutable — never mutating running machines.
Question 2: A pipeline artifact is published in one stage and consumed in a later deployment stage. Which YAML keyword downloads the artifact in the consuming stage?
- - task: CopyFiles@2
- - download: (Correct answer)
- - task: PublishBuildArtifacts@1
- - task: ExtractFiles@1
Correct answer: - download:
The 'download' step in a YAML pipeline retrieves artifacts published earlier in the same or an upstream pipeline.
Question 3: Your pipeline must deploy to 50 VMs defined in an Azure DevOps environment. Which deployment strategy minimizes risk by updating only 10 VMs at a time?
- Canary
- Recreate
- Rolling with maxParallel: 10 (Correct answer)
- Blue-green
Correct answer: Rolling with maxParallel: 10
Setting maxParallel to 10 in a rolling strategy updates exactly 10 VM targets concurrently per iteration, limiting blast radius.
Question 4: A team wants to automatically roll back a deployment if the error rate exceeds 5% within 10 minutes of release. Which combination of Azure services achieves this?
- Azure Monitor alert + Logic App
- Application Insights + Azure Monitor release gate with auto-rollback script (Correct answer)
- Azure Policy + Azure Automation
- Azure DevOps work items + build failure trigger
Correct answer: Application Insights + Azure Monitor release gate with auto-rollback script
Application Insights detects error rate spikes; a post-deployment gate queries the metric and can trigger a rollback pipeline on threshold breach.
Question 5: Which Azure Pipelines variable scope is evaluated at queue time and can be set by the person triggering the pipeline run?
- Stage-scoped variable
- Job-scoped variable
- Runtime (queue-time) variable (Correct answer)
- Environment variable
Correct answer: Runtime (queue-time) variable
Queue-time variables are defined with 'isReadonly: false' and can be overridden by the user when manually triggering a run.
Question 6: A pipeline deploys to production every time a commit is pushed to the main branch. The team wants a 30-minute soak period after staging before production deploys automatically. How is this implemented?
- Add a scheduled trigger on the production stage
- Configure a pre-deployment gate with a delay gate of 30 minutes (Correct answer)
- Use a sleep task at the start of the production stage
- Set a branch filter on the production artifact trigger
Correct answer: Configure a pre-deployment gate with a delay gate of 30 minutes
The 'Delay' release gate pauses the pipeline for a configurable duration before re-evaluating other gates and allowing the stage to proceed.
Question 7: Which Azure Container Registry feature enables you to automatically quarantine newly pushed images until a vulnerability scan completes?
- Content trust
- Geo-replication
- Quarantine policy (preview) (Correct answer)
- Token-scoped repository permissions
Correct answer: Quarantine policy (preview)
ACR's quarantine policy holds newly pushed images in a quarantined state until a scanner (like Microsoft Defender) marks them as clean.
AZ-400 Continuous Delivery 5
Which approach best supports immutable infrastructure in a continuous delivery pipeline for Azure VMs?