A Pod in namespace 'ns1' cannot resolve the Service 'db' in namespace 'ns2'. The Service exists and has ready endpoints. You verify that the Pod can resolve 'db.ns2.svc.cluster.local'. What is the most likely cause of the failure to resolve the short name 'db'?

The CoreDNS ConfigMap has a 'rewrite' rule that breaks short-name resolution

The Service 'db' in 'ns2' has no endpoints

The Pod's 'dnsPolicy' is set to 'Default'

The short name 'db' only resolves within the same namespace

Users report intermittent timeouts when accessing an application through a ClusterIP Service. You check the Service and find that the 'selectors' match the Pod labels, and 'kubectl get endpoints' shows the correct Pod IPs. The Pods themselves are healthy and respond directly. Which diagnostic step is most likely to reveal the cause of the intermittent failures?

Check the NetworkPolicy in the client Pod's namespace

Restart the CoreDNS Pods to clear cached DNS records

Check the kube-proxy logs on the node where the client Pod runs

Verify the Service's 'targetPort' matches the container's listening port

A Pod cannot resolve the Service name 'api' in the same namespace. Other Pods in the same namespace can resolve it. You check the CoreDNS ConfigMap and it is correct. What is the most likely cause specific to this Pod?

The CoreDNS Service has no endpoints

The Service 'api' has no ready endpoints

The CoreDNS ConfigMap has a 'rewrite' rule that only applies to some namespaces

The Pod's 'dnsPolicy' is set to 'Default'

A Pod cannot resolve external domain names, but it can resolve Service names. Which configuration is most likely incorrect?

The CoreDNS forwarder configuration

A Pod in namespace 'app' cannot connect to a Pod in namespace 'db' on port 5432. Both Pods are running and have correct IPs. You confirm that a NetworkPolicy in the 'db' namespace allows ingress from the 'app' namespace on port 5432. What is the most likely remaining cause of the failure?

The 'app' namespace has a NetworkPolicy that blocks all egress traffic

The CNI plugin does not support NetworkPolicies

The NetworkPolicy in the 'db' namespace also has an egress rule that blocks responses

The Service in the 'db' namespace has the wrong 'targetPort'

Certified Kubernetes Administrator (CKA)

Domain 2Objective 5

Troubleshoot Services and Networking CKA Practice Questions (Page 1)

Part of the Troubleshooting domain, which accounts for 30% of the CKA exam. Linux Foundation does not publish an official question count, but from its 120-minute exam (~50–80 total, ~15–24 in this domain), expect 3–5 from this objective — we provide 24 practice questions to prepare you well beyond it. (estimate)

24questions here

5free pages

8concepts

30%of the exam

Questions 1–5

1application · medium
A Pod in namespace 'ns1' cannot resolve the Service 'db' in namespace 'ns2'. The Service exists and has ready endpoints. You verify that the Pod can resolve 'db.ns2.svc.cluster.local'. What is the most likely cause of the failure to resolve the short name 'db'?
Select an answer first
2application · medium
Users report intermittent timeouts when accessing an application through a ClusterIP Service. You check the Service and find that the 'selectors' match the Pod labels, and 'kubectl get endpoints' shows the correct Pod IPs. The Pods themselves are healthy and respond directly. Which diagnostic step is most likely to reveal the cause of the intermittent failures?
Select an answer first
3application · medium
A Pod cannot resolve the Service name 'api' in the same namespace. Other Pods in the same namespace can resolve it. You check the CoreDNS ConfigMap and it is correct. What is the most likely cause specific to this Pod?
Select an answer first
4foundation · easy
A Pod cannot resolve external domain names, but it can resolve Service names. Which configuration is most likely incorrect?
Select an answer first
5application · medium
A Pod in namespace 'app' cannot connect to a Pod in namespace 'db' on port 5432. Both Pods are running and have correct IPs. You confirm that a NetworkPolicy in the 'db' namespace allows ingress from the 'app' namespace on port 5432. What is the most likely remaining cause of the failure?
Select an answer first

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