Istio and gRPC seem complementary and I'd like to use both in the clusters.
The thing is that they both add an extra container which receives/proxy communication between pods / microservices.
Is it advised or not to use both in parallel in all pods?
Are there particular adaptations to do if one uses both?
Istio and gRPC do work well together, when declaring your services ports' to istio just make sure to name them grpc-something so the proxy knows it is h2/grpc traffic and route it properly
You mention that gRPC adds an extra container - why not having your service speak gRPC natively ?
We do have future plans with protocol transcoding and rich integrated gRPC/istio libraries that would skip layers but that's not there yet.