HTTP probe configuration in Kubernetes - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the result of this HTTP readiness probe configuration?

Given this Kubernetes pod snippet, what will be the HTTP probe's behavior when the container is starting?

Kubernetes

readinessProbe:
  httpGet:
    path: /healthz
    port: 8080
  initialDelaySeconds: 5
  periodSeconds: 10
  failureThreshold: 3

A The probe checks /healthz immediately on container start, then every 5 seconds; after 10 failures, it marks the pod as not ready.

B The probe waits 5 seconds before first check, then checks /healthz every 10 seconds; after 3 failures, it marks the pod as not ready.

C The probe waits 3 seconds before first check, then checks /healthz every 5 seconds; after 5 failures, it marks the pod as not ready.

D The probe waits 10 seconds before first check, then checks /healthz every 3 seconds; after 1 failure, it marks the pod as not ready.

💡 Hint

Look at initialDelaySeconds, periodSeconds, and failureThreshold values carefully.

initialDelaySeconds sets the wait before first probe; periodSeconds sets interval between probes; failureThreshold is how many failures before marking not ready.

❓ Configuration

intermediate

Identify the correct HTTP liveness probe configuration for port 80 and path /status

Which option correctly configures a liveness probe that checks HTTP path /status on port 80 every 15 seconds with a timeout of 5 seconds?

A

livenessProbe:
  httpGet:
    path: /status
    port: 80
  periodSeconds: 15
  timeoutSeconds: 5

B

livenessProbe:
  httpGet:
    path: /status
    port: 8080
  periodSeconds: 15
  timeoutSeconds: 5

C

livenessProbe:
  httpGet:
    path: /health
    port: 80
  periodSeconds: 10
  timeoutSeconds: 5

D

livenessProbe:
  tcpSocket:
    port: 80
  periodSeconds: 15
  timeoutSeconds: 5

💡 Hint

Check the port number and path carefully; also probe type must be HTTP.

Option A matches the required path /status, port 80, period 15s, and timeout 5s using httpGet.

❓ Troubleshoot

advanced

Why does this HTTP readiness probe always fail?

A pod has this readiness probe: readinessProbe: httpGet: path: /ready port: 8080 initialDelaySeconds: 10 periodSeconds: 5 failureThreshold: 1 The container starts but the pod never becomes ready. What is the most likely cause?

A The /ready endpoint is not responding with HTTP 200 status code, causing probe failures.

B The failureThreshold is too high, so the pod never marks ready.

C The initialDelaySeconds is too short, so the probe runs before container starts.

D The port 8080 is incorrect; readiness probes do not support ports above 8000.

💡 Hint

Check what the probe expects from the HTTP endpoint.

Readiness probes expect HTTP 200 response; if /ready returns other status, probe fails and pod stays not ready.

🔀 Workflow

advanced

Order the steps to add an HTTP liveness probe to a Kubernetes deployment

Put these steps in the correct order to add an HTTP liveness probe to a deployment YAML:

A 3,1,2,4

B 2,1,3,4

C 1,3,2,4

D 1,2,3,4

💡 Hint

Think about editing first, then applying, then verifying.

First edit YAML, then apply changes, then verify pod status, finally check logs for restarts.

✅ Best Practice

expert

Which HTTP probe configuration best balances fast failure detection and avoiding false positives?

Choose the HTTP liveness probe configuration that best balances detecting real failures quickly without causing unnecessary container restarts.

A initialDelaySeconds: 0, periodSeconds: 2, failureThreshold: 5, timeoutSeconds: 10

B initialDelaySeconds: 5, periodSeconds: 5, failureThreshold: 1, timeoutSeconds: 1

C initialDelaySeconds: 30, periodSeconds: 10, failureThreshold: 3, timeoutSeconds: 5

D initialDelaySeconds: 60, periodSeconds: 60, failureThreshold: 1, timeoutSeconds: 1

💡 Hint

Consider initial delay, probe frequency, failure tolerance, and timeout together.

Option C waits enough before probing, checks regularly, allows some failures, and has reasonable timeout to avoid false positives.