CKA Services and Networking Practice Question
Which TWO of the following are valid ways to isolate a set of pods from all ingress traffic except from monitoring pods?
⚠ Common exam trap
A common mix-up: candidates confuse `namespaceSelector` with `podSelector` and think a namespace-level rule is sufficient to isolate traffic to specific pods, but without a `podSelector` in the ingress rule, all pods in the monitoring namespace are allowed, breaking isolation.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Apply a NetworkPolicy with podSelector: matchLabels: { app: myapp }, ingress: [ { from: [ { podSelector: { matchLabels: { role: monitoring } } } ] } ]
It uses a NetworkPolicy with a `podSelector` targeting the protected pods and an `ingress` rule that explicitly allows traffic only from pods with the label `role: monitoring`. This isolates the target pods from all other ingress traffic, as Kubernetes NetworkPolicy defaults to denying ingress when any ingress rule is defined, and only the specified source pods are permitted.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Apply a NetworkPolicy with ingress rule allowing from a specific pod only
Why it's wrong here
This alone does not deny other traffic; you need a default deny policy.
- ✗
Apply a NetworkPolicy with empty podSelector and ingress rule allowing all
Why it's wrong here
This would allow all ingress to all pods.
- ✗
Apply a NetworkPolicy with podSelector: matchLabels: { app: myapp } and ingress rule with namespaceSelector: { matchLabels: { name: monitoring } }
Why it's wrong here
This selects pods in monitoring namespace, not the monitoring pods themselves.
- ✓
Apply a NetworkPolicy with podSelector: matchLabels: { app: myapp }, ingress: [ { from: [ { podSelector: { matchLabels: { role: monitoring } } } ] } ]
Why this is correct
This allows ingress from monitoring pods.
- ✓
Apply a NetworkPolicy with podSelector: matchLabels: { app: myapp }, policyTypes: [Ingress], and no ingress rules
Why this is correct
This denies all ingress by default.
Go deeper
Related to this question
Learn chapter
Kubernetes Architecture Overview
Key term
Ingress Resources
Ingress Resources are Kubernetes API objects that manage external access to services inside a cluster, typically HTTP and HTTPS traffic, by defining rules for routing requests based on hostnames and paths.
Key term
Network Policies
A Kubernetes resource that controls how pods communicate with each other and with other network endpoints, acting as a firewall for pod-to-pod traffic.
About these practice questions
Courseiva writes every CKA question from scratch — 302 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This CKA practice question is part of Courseiva's free CNCF certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the CKA exam.