Feature flags in Kubernetes - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a feature flag in Kubernetes?

A feature flag is a way to turn features on or off in your application without changing the code. In Kubernetes, it helps control new features safely by toggling them using configuration.

beginner

How can ConfigMaps be used for feature flags in Kubernetes?

ConfigMaps store configuration data as key-value pairs. You can use them to hold feature flag values and mount them into pods so your app reads the flags and enables or disables features accordingly.

beginner

What is the benefit of using feature flags in Kubernetes deployments?

Feature flags let you release new features gradually, test them in production, and quickly disable them if problems occur, all without redeploying your app.

intermediate

Which Kubernetes resource is commonly used to manage feature flags dynamically?

ConfigMaps are commonly used because they can be updated without restarting pods, allowing feature flags to change dynamically.

intermediate

How does a pod access feature flags stored in a ConfigMap?

A pod can mount the ConfigMap as a volume or use environment variables from the ConfigMap. The application inside the pod reads these values to decide which features to enable.

What Kubernetes object is best suited to store feature flag settings?

A Service

B Pod

C Deployment

D ConfigMap

ConfigMaps store configuration data like feature flags, separate from application code.

How can feature flags be updated without redeploying an application in Kubernetes?

A By restarting the pod manually

B By updating the ConfigMap and letting pods reload it

C By changing the container image

D By deleting the deployment

Updating the ConfigMap allows pods to get new flag values without redeploying the app.

What is a key advantage of using feature flags in production?

A Enable or disable features instantly without code changes

B Increase pod memory automatically

C Scale the number of pods

D Change container images

Feature flags let you toggle features on or off instantly without changing code.

Which method can a pod use to access feature flags from a ConfigMap?

A Access Deployment specs

B Use a Service to fetch flags

C Mount ConfigMap as a volume or use environment variables

D Read from a Secret

Pods can mount ConfigMaps as files or environment variables to read feature flags.

Why is it useful to use feature flags during gradual rollouts?

A To control which users see new features safely

B To increase CPU limits

C To change pod labels

D To update container images

Feature flags help release features to some users first, reducing risk.

Explain how feature flags work in Kubernetes and why they are useful.

Think about how you can turn features on or off without changing code.

Describe the steps to implement a feature flag using a ConfigMap in Kubernetes.

Focus on ConfigMap creation, pod access, and dynamic updates.