Q-10 — Cert-Manager CRDs & Documentation Extraction

Task:

Verify the cert-manager application which has been deployed in the cluster.

1. Create a list of all cert-manager Custom Resource Definitions (CRDs) and save it to:

~/resources.yaml

~/subject.yaml

✅ SOLUTION — Step by Step (Fast for Exam)

1️⃣ Verify cert-manager is installed

kubectl get ns
kubectl get pods -n cert-manager

You should see pods like:

• cert-manager
• cert-manager-webhook
• cert-manager-cainjector

2️⃣ List all cert-manager CRDs → save to ~/resources.yaml

⚠ VERY IMPORTANT: The question says:

make sure kubectl’s default output format is used do not set an output format

So you must not use -o yaml, -o json, etc.

Use this exact command:

kubectl get crds | grep cert-manager > ~/resources.yaml

✔ Uses default table output ✔ No -o flag ✔ Matches exam requirement 100%

3️⃣ Extract documentation for the subject field of the Certificate CRD

First, check the CRD name:

kubectl get crd | grep certificate

You will likely find:

certificates.cert-manager.io

Now get schema documentation using the recommended exam-safe method:

kubectl explain certificate.spec.subject > ~/subject.yaml

✔ kubectl explain = official documentation ✔ Allowed to use any output format for this part ✔ Output automatically comes in plain text YAML-ish documentation ✔ Exactly matches exam instruction

🎉 FINAL ANSWER SUMMARY

File 1: ~/resources.yaml

kubectl get crds | grep cert-manager > ~/resources.yaml

File 2: ~/subject.yaml

kubectl explain certificate.spec.subject > ~/subject.yaml

🔥 Exam Tip (Very Important)

• If you use kubectl get crds -o yaml → FAIL
• If you use kubectl get crds -o json → FAIL
• Only the default table output is allowed for /resources.yaml.