Startup probe concept in Kubernetes - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a startup probe in Kubernetes?

A startup probe checks if an application inside a container has started successfully before other health checks run.

intermediate

Why use a startup probe instead of just readiness or liveness probes?

Startup probes help avoid killing containers that take a long time to start by delaying liveness and readiness checks until the app is ready.

beginner

Which Kubernetes probe runs first during container startup?

The startup probe runs first to confirm the app has started before readiness and liveness probes begin.

intermediate

What happens if a startup probe fails repeatedly?

Kubernetes will kill the container and try to restart it, assuming the app failed to start properly.

intermediate

How do you define a startup probe in a pod spec?

You add a 'startupProbe' section with parameters like 'exec', 'httpGet', or 'tcpSocket' to check app startup.

What is the main purpose of a startup probe in Kubernetes?

A To check if the app has started before other probes run

B To monitor CPU usage of the container

C To check network connectivity

D To update container images automatically

Startup probes verify the app has started before readiness and liveness probes begin.

Which probe runs only after the startup probe succeeds?

A Startup probe

B Readiness probe

C Liveness probe

D None of the above

Readiness and liveness probes start only after the startup probe confirms the app has started.

If a startup probe fails, what does Kubernetes do?

A Scales the pod up

B Ignores the failure

C Runs readiness probe instead

D Restarts the container

Kubernetes restarts the container if the startup probe fails repeatedly.

Which of these can be used in a startup probe configuration?

A All of the above

B httpGet request

C exec command

D tcpSocket check

Startup probes support exec, httpGet, and tcpSocket checks.

Why might you add a startup probe to a slow-starting application?

A To speed up container startup

B To prevent premature container restarts

C To disable readiness probes

D To increase CPU limits

Startup probes prevent Kubernetes from killing containers that take longer to start.

Explain how a startup probe works and why it is useful in Kubernetes.

Think about the order of health checks and container restarts.

Describe how to configure a startup probe in a Kubernetes pod specification.

Look at the pod YAML and probe parameters.