Is it possible to run PostgreSQL as a service inside an OpenShift cluster and get external traffic to it via an exposed route (the recommended default way for communicating from the outside)?
The OpenShift 3.9 documentation states this:
A router is configured to accept external requests and proxy them based on the configured routes. This is limited to HTTP/HTTPS(SNI)/TLS(SNI), which covers web applications.
PostgreSQL can to SSL and it can be configured to listen on port 443 (HTTPS), but I think it cannot do SNI yet. I would only run a single pod behind the service, so load balancing should not cause issues. If feasible, I would expect to connect into the cluster and to the service with psql -h ....
I have come to the (preliminary) conclusion that OpenShift port forwarding (oc port-forward) offers the best way (well ... :) forward in this situation.