kubectl logs for debugging in Kubernetes - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the command kubectl logs <pod-name> do?

It shows the logs (output messages) from the main container inside the specified pod. This helps to see what the application inside the pod is doing or if there are any errors.

beginner

How do you view logs from a specific container in a pod with multiple containers?

Use kubectl logs <pod-name> -c <container-name> to get logs from the chosen container inside the pod.

beginner

What option shows logs continuously as new lines are added?

The -f or --follow option streams the logs live, like watching a live feed. Example: kubectl logs -f <pod-name>.

intermediate

How can you get logs from previous instances of a container that crashed?

Use kubectl logs <pod-name> -c <container-name> --previous to see logs from the last terminated container.

beginner

Why is kubectl logs useful for debugging?

It helps you see what is happening inside your app running in Kubernetes. You can find errors, warnings, or understand app behavior without accessing the pod directly.

Which command streams logs live from a pod?

A kubectl get pods

B kubectl exec pod-name

C kubectl describe pod pod-name

D kubectl logs -f pod-name

The -f option in kubectl logs streams logs live as they are generated.

How do you get logs from a specific container in a pod?

A kubectl logs pod-name -c container-name

B kubectl logs pod-name --all-containers

C kubectl get logs container-name

D kubectl describe container container-name

The -c option specifies the container name inside the pod for logs.

What does the --previous flag do in kubectl logs?

A Shows logs from all containers

B Shows logs from the last terminated container

C Shows logs from the current running container

D Restarts the pod

The --previous flag shows logs from the container instance before it crashed or restarted.

Which command is NOT used to view logs?

A kubectl describe pod pod-name

B kubectl logs pod-name -f

C kubectl logs pod-name

D kubectl logs pod-name -c container-name

kubectl describe shows pod details but not logs.

Why use kubectl logs for debugging?

A To create new pods

B To delete pods

C To see app output and errors inside pods

D To update Kubernetes version

kubectl logs helps check what the app inside the pod is doing or if it has errors.

Explain how to use kubectl logs to debug a pod with multiple containers.

Think about how to target one container inside a pod.

Describe how to view logs from a crashed container to find out what went wrong.

Look for logs from the last terminated container.