An IP address identifies where a pod can be reached on the cluster network. Each pod has its own network interface and IP address. Containers in the same pod share that address and its port space; containers in different pods communicate across the pod network. section 11.0 section 3.3.1
A pod can send traffic directly to another pod when it knows the destination IP address and application port. This works across worker nodes: direct pod-to-pod packets retain their source and destination IP addresses and ports, so the receiving pod sees the sender’s IP address. section 11.0
$ kubectl get pod kiada -o wide NAME READY STATUS RESTARTS AGE IP NODE ... kiada 1/1 Running 0 35m 10.244.2.4 worker2 ...
Run `kubectl get pod kiada -o wide` to find the pod’s address in the IP column. You can also find it in the pod’s status under `podIP`. section 5.3.1
Choose how to reach the application based on where the client runs:
- From another pod, send the request to the destination pod’s IP address and listening port; for example, `curl 10.244.2.4:8080`. section 5.3.1
- From your local computer, do not assume the pod IP is reachable: it is typically internal to the cluster. For development or debugging, run `kubectl port-forward kiada 8080`, then request `localhost:8080`. section 5.3.1
- Use a Service when you want traffic forwarded to pods rather than a direct connection to one specific pod. section 5.3.1
The IP address alone does not tell you which port the application listens on. Listing container ports in a pod definition helps readers discover the intended port, but omitting that list does not prevent connections to a port the container accepts. section 5.3.1
