Allow two pods (say pod A and B) running in same/different namespace communicate irrespective of the protocol(say http,https,akka.tcp) along with a valid Network policy applied.
Solutions tried:
Tried applying network policy to both the pods and also used the service name: “my-svc.my-namespace.svc.cluster.local” to make pod B communicate to pod A which is running the service “my-svc” but both failed to communicate.
Also tried adding the IP address and host mapping of pod A in pod B while it’s deployment, then pod B was able to communicate to pod A but inverse communication is failing.
Kindly suggest me a way to fix this.
By default, pods can communicate with each other by their IP address, regardless of the namespace they're in.
You can see the IP address of each pod with:
kubectl get pods -o wide --all-namespacesHowever, the normal way to communicate within a cluster is through Service resources.
A Service also has an IP address and additionally a DNS name. A Service is backed by a set of pods. The Service forwards requests to itself to one of the backing pods.
The fully qualified DNS name of a Service is:
<service-name>.<service-namespace>.svc.cluster.localThis can be resolved to the IP address of the Service from anywhere in the cluster (regardless of namespace).
For example, if you have:
ns-a: Service svc-a → set of pods Ans-b: Service svc-b → set of pods BThen a pod of set A can reach a pod of set B by making a request to:
svc-b.ns-b.svc.cluster.localYou can put the Pods behind Services and use Service DNS for communication. Calls to service-name allow Pods in the same namespace to communicate. Calls to service-name.namespace allow Pods in different namespaces to communicate.