DOL CI/CD Pipeline 3

Question 1

A deployment pipeline passes all automated tests but the production release still causes user-facing errors. Which practice would most likely have caught this gap?

Accepted Answer

Implementing synthetic monitoring and real-user monitoring (RUM) post-deployment

Answer

Adding more unit tests to the pipeline

Answer

Running the pipeline twice before deploying

Answer

Requiring a longer manual QA freeze period

Question 2

What distinguishes a 'blue-green deployment' from a 'rolling deployment'?

Accepted Answer

Blue-green switches all traffic instantly between two identical environments; rolling updates instances incrementally

Answer

Blue-green requires twice the infrastructure permanently; rolling uses none

Answer

Blue-green is only suitable for containerized workloads; rolling works on VMs

Answer

Blue-green always requires a database migration step; rolling does not

Question 3

A team uses Docker images as pipeline artifacts. What is the best practice for ensuring image immutability across environments?

Accepted Answer

Build once, tag with the commit SHA, and promote the same image across all environments

Answer

Rebuild the Docker image fresh for each environment (dev, staging, prod)

Answer

Tag images with 'latest' and pull on each deployment

Answer

Store Dockerfiles in each environment's configuration repository separately

Question 4

Which CI/CD pattern ensures that a deployment does not proceed if monitoring dashboards show elevated error rates after an initial traffic shift?

Accepted Answer

Progressive delivery with automated rollback triggers based on observability signals

Answer

Manual approval gates before every deployment

Answer

Scheduled maintenance windows for all deployments

Answer

Feature branch deployments that bypass production monitoring

Question 5

When implementing database migrations in a CI/CD pipeline, what approach prevents downtime during schema changes?

Accepted Answer

Apply forward-only, backward-compatible migrations so old and new code run simultaneously

Answer

Drop and recreate the entire schema with each deployment

Answer

Pause the pipeline until the database team manually applies changes

Answer

Use a separate database per pipeline stage with no shared schema

Question 6

A DevOps leader wants to reduce the 'change failure rate' on her team. Which pipeline improvement directly targets this metric?

Accepted Answer

Strengthening automated test coverage and adding contract testing between services

Answer

Increasing deployment frequency by removing all approval gates

Answer

Moving from weekly to daily deployments immediately

Answer

Consolidating all microservices into a monolith to simplify testing

Question 7

In a Kubernetes-based CD pipeline, what is the purpose of a 'readiness probe'?

Accepted Answer

To signal that a pod is ready to receive traffic, preventing premature routing during rolling updates

Answer

To restart crashed containers automatically

Answer

To measure container resource consumption for autoscaling decisions

Answer

To enforce network policies between namespaces