Kubernetes · Follow the flow

How a customer reaches the shop

After DNS lookup, a request reaches the public entry point, an HTTP controller, and a ready application Pod.

How a customer reaches the shopAfter DNS lookup, a request reaches the public entry point, an HTTP controller, and a ready application Pod.STEP 1Browser + DNS lookupshop.example.com → IP.Browser learns the address.STEP 2Public entry pointReachable load balanceraccepts the connection.STEP 3Ingress controllerHandle HTTPS here.Match the host and path.STEP 4Service → endpointshop-service selectsready Pod endpoints.STEP 5Application PodShop handles the request.Build the response.STEP 6Response to customerReply over the connection.Browser shows the page.Read the numbered stages. Press Play to follow them.Arrows show the order of this explanation, not every network connection.

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The Service stage is logical: some controllers send directly to endpoints instead of through a ClusterIP. DNS, the API server, etcd and the scheduler are not web traffic forwarding hops. The exact load balancer and network path depend on the implementation.