Consul to consul connect incremental migration

Hello!

My question is regarding a path for incremental migration. Let’s assume I have used Consul service discovery for a while, and I would like to migrate to Connect. But forcing Connect on everybody is not really an option. Thus, I would like to deploy, for starters, Envoy proxy on a few selected services, see how they work, then gradually have everybody join the mesh.

The most important feature I’m looking for is have Service A registering to Consul, without sidecar, then have it defined as upstream in Service B, which uses Envoy. So service B would need to know only the port on localhost where to connect, and from there Envoy routing and service discovery capabilities take over.

Is that even possible ?

Thank you!