[Question] Enable in-mesh pod to communicate with another in-mesh pod using PodIP (mTLS enabled)

Fundamentally, Istio is designed to work with services, not direct Pod IPs. It is a Service Mesh afterall.

If your application is designed to directly use pod IPs you have a couple of options:

  1. Disable Istio for this communication
  2. Add a new ServiceEntry manually that identifies the IP address and associates it with a “service.” In this ServiceEntry, set addresses to the pod IP, and resolution to NONE.

Using (2) for a Pod IP is likely to be brittle. If the pod goes down and is rescheduled with a new IP, connectivity to it will break until you update the ServiceEntry.