I've Docker Desktop Kubernetes cluster setup in my local machine and it is working fine. Now i'm trying to deploy .Net Core gRPC server and .Net core Console load generator to my cluster.

I'm using VisualStudio(2019)'s default template for gRPC application

Server:

proto file

syntax = "proto3";

option csharp_namespace = "KubernetesLoadSample";

package greet;

// The greeting service definition.
service Greeter {
  // Sends a greeting
  rpc SayHello (HelloRequest) returns (HelloReply);
}

// The request message containing the user's name.
message HelloRequest {
  string name = 1;
}

// The response message containing the greetings.
message HelloReply {
  string message = 1;
}

.net core gRPC application

public class GreeterService : Greeter.GreeterBase
{
    private readonly ILogger<GreeterService> _logger;
    public GreeterService(ILogger<GreeterService> logger)
    {
        _logger = logger;
    }

    public override Task<HelloReply> SayHello(HelloRequest request, ServerCallContext context)
    {
        _logger.LogInformation("Compute started");
        double result = 0;
        for (int i = 0; i < 10000; i++)
        {
            for (int j = 0; j < i; j++)
            {
                result += Math.Sqrt(i) + Math.Sqrt(j);
            }
        }
        return Task.FromResult(new HelloReply
        {
            Message = "Completed"
        }); ;
    }
}

and DockerFile for this project as follows,

FROM mcr.microsoft.com/dotnet/aspnet:3.1 AS base
WORKDIR /app
EXPOSE 80
EXPOSE 443

FROM mcr.microsoft.com/dotnet/sdk:3.1 AS build
WORKDIR /src
COPY ["KubernetesLoadSample.csproj", "KubernetesLoadSample/"]
RUN dotnet restore "KubernetesLoadSample/KubernetesLoadSample.csproj"

WORKDIR "/src/KubernetesLoadSample"
COPY . .
RUN dotnet build "KubernetesLoadSample.csproj" -c Release -o /app/build

FROM build AS publish
RUN dotnet publish "KubernetesLoadSample.csproj" -c Release -o /app/publish

FROM base AS final
WORKDIR /app
COPY --from=publish /app/publish .
ENTRYPOINT ["dotnet", "KubernetesLoadSample.dll"]

i was able to check this image working locally using

PS C:\Users\user> docker run -it -p 8000:80 kubernetesloadsample:latest
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: http://[::]:80
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Production
info: Microsoft.Hosting.Lifetime[0]
      Content root path: /app
info: KubernetesLoadSample.GreeterService[0]
      Compute started // called from BloomRPC Client

Client

Client is a .net console application, that calls server in a loop

    static async Task Main(string[] args)
    {
        var grpcServer = Environment.GetEnvironmentVariable("GRPC_SERVER");
        Channel channel = new Channel($"{grpcServer}", ChannelCredentials.Insecure);

        Console.WriteLine($"Sending load to port {grpcServer}");
        while(true)
        {
            try
            {
                var client = new Greeter.GreeterClient(channel);
                var reply = await client.SayHelloAsync(
                                  new HelloRequest { Name = "GreeterClient" });

                Console.WriteLine("result: " + reply.Message);
                await Task.Delay(1000);
            }
            catch (Exception ex)
            {
                Console.WriteLine($"{DateTime.UtcNow} : tried to connect : {grpcServer}  Crashed : {ex.Message}");
            }
        }
    }

Docker file for client:

FROM mcr.microsoft.com/dotnet/aspnet:3.1 AS base
WORKDIR /app
EXPOSE 80
EXPOSE 443

FROM mcr.microsoft.com/dotnet/sdk:3.1 AS build
WORKDIR /src
COPY ["GrpcClientConsole.csproj", "GrpcClientConsole/"]
RUN dotnet restore "GrpcClientConsole/GrpcClientConsole.csproj"

WORKDIR "/src/GrpcClientConsole"
COPY . .
RUN dotnet build "GrpcClientConsole.csproj" -c Release -o /app/build

FROM build AS publish
RUN dotnet publish "GrpcClientConsole.csproj" -c Release -o /app/publish

FROM base AS final
WORKDIR /app
COPY --from=publish /app/publish .
ENTRYPOINT ["dotnet", "GrpcClientConsole.dll"]

and deployment file as follows,

---
apiVersion: v1
kind: Namespace
metadata:
  name: core-load
---
apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  name: compute-server
  namespace: core-load
spec:
  replicas: 4
  selector:
    matchLabels:
      app: compute-server-svc
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: compute-server-svc
    spec:
      containers:
      - env:
        image: kubernetesloadsample:latest
        imagePullPolicy: Never
        name: compute-server-svc
        ports:
        - containerPort: 80
          name: grpc
        resources: {}
status: {}
---
apiVersion: v1
kind: Service
metadata:
  name: compute-server-svc
  namespace: core-load
spec:
  clusterIP: None
  
  ports:
  - name: grpc
    port: 5000
    targetPort: 80
    protocol: TCP
  selector:
    app: compute-server-svc
---
apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  name: compute-client
  namespace: core-load
spec:
  replicas: 1
  selector:
  
    matchLabels:
      app: compute-client
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: compute-client
    spec:
      containers:
      - env:
        - name: GRPC_SERVER
          value: compute-server-svc.core-load.svc.cluster.local:5000
        image: grpc-client-console:latest
        imagePullPolicy: Never
        name: compute-client
        resources: {}
status: {}
---

Problem

client is not able to connect gRPC server with this compute-server-svc.core-load.svc.cluster.local:5000 name. I tried compute-server-svc.core-load this as well, but facing below issue

PS E:\study\core\k8sgrpc\KubernetesLoadSample> k get pods -n core-load
NAME                              READY   STATUS    RESTARTS   AGE
compute-client-bff5f666-cjwf5     1/1     Running   0          15s
compute-server-545567f589-5blkv   1/1     Running   0          15s
compute-server-545567f589-bv4r2   1/1     Running   0          15s
compute-server-545567f589-mdp2x   1/1     Running   0          15s
compute-server-545567f589-wdff5   1/1     Running   0          15s
PS E:\study\core\k8sgrpc\KubernetesLoadSample> k logs compute-client-bff5f666-cjwf5 -n  core-load --tail 5
07/09/2021 17:18:35 : tried to connect : compute-server-svc.core-load.svc.cluster.local:5000 Crashed : Status(StatusCode=Unavailable, Detail="failed to connect to all addresses")
07/09/2021 17:18:35 : tried to connect : compute-server-svc.core-load.svc.cluster.local:5000 Crashed : Status(StatusCode=Unavailable, Detail="failed to connect to all addresses")
07/09/2021 17:18:35 : tried to connect : compute-server-svc.core-load.svc.cluster.local:5000 Crashed : Status(StatusCode=Unavailable, Detail="failed to connect to all addresses")
07/09/2021 17:18:35 : tried to connect : compute-server-svc.core-load.svc.cluster.local:5000 Crashed : Status(StatusCode=Unavailable, Detail="failed to connect to all addresses")
07/09/2021 17:18:35 : tried to connect : compute-server-svc.core-load.svc.cluster.local:5000 Crashed : Status(StatusCode=Unavailable, Detail="failed to connect to all addresses")

I didnt get any solution from the stackoverflow questions similar to this, so im creating this.

Can anyone please let me know what i've missed or doing wrong?

TIA