You have a multi-namespace Kubernetes cluster with services named api in namespaces dev and prod. How can a pod in dev namespace connect to the api service in prod namespace using DNS?
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Kubernetes - Services
You have a multi-namespace Kubernetes cluster with services named api in namespaces dev and prod. How can a pod in dev namespace connect to the api service in prod namespace using DNS?
AUse the full DNS name <code>api.prod.svc.cluster.local</code>
BUse just <code>api</code> since it resolves across namespaces
CUse <code>api.dev.svc.cluster.local</code> and specify namespace in config
DUse the IP address of the <code>prod</code> service directly
Step-by-Step Solution
Solution:
Step 1: Understand cross-namespace DNS resolution
Within a namespace, service names resolve locally; cross-namespace requires full DNS name.
Step 2: Apply full DNS name for cross-namespace access
To reach api in prod from dev, use api.prod.svc.cluster.local.
Final Answer:
Use the full DNS name api.prod.svc.cluster.local -> Option A
Quick Check:
Cross-namespace = full DNS name [OK]
Quick Trick:Cross-namespace access needs full DNS name service.namespace.svc.cluster.local [OK]
Common Mistakes:
Assuming service name alone resolves across namespaces
Using wrong namespace in DNS name
Relying on IP addresses which can change
Master "Services" in Kubernetes
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