Service

A Service provides a stable network endpoint to access Pods.

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Pods are unstable:

• IP changes when restarted
• Pods can be recreated anytime

Service solves this problem by providing:

• Stable DNS name
• Stable IP inside cluster

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Service: my-api → routes to Pod A → routes to Pod B

Even if Pods change:

• Service stays the same

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• ClusterIP → internal only
• NodePort → access via node port
• LoadBalancer → external cloud access
• ExternalName → DNS mapping

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Service = “front door”

Users do NOT talk to Pods directly. They talk to the Service.