CKA Container Fundamentals 5

Question 1

What is the purpose of a Kubernetes ephemeral container?

Accepted Answer

To inject a debugging container into a running pod without restarting it

Answer

Ephemeral containers can be added to an already-running pod for debugging purposes, sharing the pod's namespaces without requiring a pod restart.

Question 2

How does the 'shareProcessNamespace: true' pod setting affect containers?

Accepted Answer

All containers in the pod can see and signal each other's processes

Answer

shareProcessNamespace: true makes all containers in a pod share a single PID namespace, so each can see and interact with the other containers' processes.

Question 3

What does a container's liveness probe failure cause Kubernetes to do?

Accepted Answer

Restart the failing container

Answer

When a liveness probe fails, kubelet restarts the specific container that failed, allowing recovery from deadlocked or hung application states.

Question 4

Which container image layer is added last and represents application code in a typical Dockerfile?

Accepted Answer

The application layer added by COPY or ADD instructions

Answer

Application code (COPY/ADD) is typically added in the final layers so that code changes invalidate only the last few cache layers, not the larger dependency layers.

Question 5

What happens when a container's memory usage exceeds its memory limit in Kubernetes?

Accepted Answer

The container is OOMKilled (killed by the Out-of-Memory killer)

Answer

When a container exceeds its memory limit, the Linux OOM killer terminates the container process and Kubernetes records it as OOMKilled, then restarts the container per the restartPolicy.

(CKA) Certified Kubernetes Associate Practice Test

(CKA) Certified Kubernetes Associate Practice Test

CKA Container Fundamentals 5