Executing commands in Pods in Kubernetes - Cheat Sheet & Quick Revision

Recall & Review

beginner

What command is used to execute a command inside a running Kubernetes Pod?

The command kubectl exec is used to run commands inside a running Pod.

beginner

How do you start an interactive shell session inside a Pod named my-pod?

Use kubectl exec -it my-pod -- /bin/sh or kubectl exec -it my-pod -- /bin/bash to start an interactive shell.

beginner

What does the -it flag mean in kubectl exec?

-i means interactive (keeps stdin open), and -t allocates a terminal. Together they allow interactive shell sessions.

intermediate

Can you execute commands in a specific container inside a Pod with multiple containers? How?

Yes, use kubectl exec -it pod-name -c container-name -- command to target a specific container.

beginner

What happens if you run kubectl exec on a Pod that is not running?

The command will fail because the Pod must be in a running state to execute commands inside it.

Which command runs an interactive bash shell inside a Pod named 'web-server'?

A kubectl exec -it web-server -- /bin/bash

B kubectl run web-server -- /bin/bash

C kubectl start web-server -bash

D kubectl shell web-server

Option A uses the correct syntax to execute an interactive bash shell inside the Pod.

What does the -- signify in the command kubectl exec pod-name -- ls?

A Ends the command execution

B Separates kubectl flags from the command to run inside the Pod

C Specifies the Pod namespace

D Indicates the Pod name

The -- separates kubectl options from the command to run inside the Pod.

How do you specify a container inside a Pod when executing a command?

A --container container-name

B -p container-name

C -c container-name

D -n container-name

The -c flag specifies the container name inside the Pod.

If you want to run a non-interactive command like ls / inside a Pod, which flag is NOT necessary?

A -c

B -i

C --

D -t

The -t flag allocates a terminal and is not needed for non-interactive commands.

What will happen if you try to exec into a Pod that is in 'Pending' state?

A The command will fail because the Pod is not running

B You will get a shell prompt

C The Pod will start automatically

D kubectl will restart the Pod

You cannot exec into a Pod unless it is running.

Explain how to run an interactive shell inside a Kubernetes Pod and why the flags used are important.

Think about how you connect to a remote computer's terminal.

Describe how to execute a command inside a specific container when a Pod has multiple containers.

Imagine a Pod like a small apartment with multiple rooms (containers).