Not able to connect to gRPC Server with revert proxy (HAProxy) from client through SSL

Question

In my project using gRPC Java,I am using OpenSSL to make a secure connection between Client and Server through a revert proxy (HAProxy).

Since Client and Server interacting through a revert proxy, therefore I only config SSL for HAProxy, there's no need to do anything with the Server. So:

• Client <-> Proxy: TLS/SSL
• Proxy <-> Server: Raw data

I managed to run the server successfully and configured SSL at HAProxy, I checked SSL configuration with https://www.digicert.com/help/ and everything is ok.

The documentation here mentions that the client code for a secure channel is this:

ManagedChannel channel = ManagedChannelBuilder.forAddress("myservice.example.com", 443).build();
GreeterGrpc.GreeterStub stub = GreeterGrpc.newStub(channel);

And this is my code:

channel = ManagedChannelBuilder
                    .forAddress(domain, port)
                    .usePlaintext(false)
                    .build();
interceptChannel = ClientInterceptors.intercept(channel, new ClientHeaderInterceptor());
asyncStub = GatewayServiceGrpc.newStub(channel);
blockingStub = GatewayServiceGrpc.newBlockingStub(interceptChannel);

But the problem is I can't connect to the Server, no response and it doesn't throw any excetion or error at all.

But if I change usePlaintext from false to true (disable TLS) from client and Proxy is still having SSL, then I receive this exception:

io.grpc.StatusRuntimeException: UNAVAILABLE: Network closed for unknown reason
        at io.grpc.Status.asRuntimeException(Status.java:526)
        at io.grpc.stub.ClientCalls$StreamObserverToCallListenerAdapter.onClose(ClientCalls.java:385)
        at io.grpc.ForwardingClientCallListener.onClose(ForwardingClientCallListener.java:41)
        at io.grpc.internal.CensusTracingModule$TracingClientInterceptor$1$1.onClose(CensusTracingModule.java:339)
        at io.grpc.internal.ClientCallImpl.closeObserver(ClientCallImpl.java:443)
        at io.grpc.internal.ClientCallImpl.access$300(ClientCallImpl.java:63)
        at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl.close(ClientCallImpl.java:525)
        at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl.access$600(ClientCallImpl.java:446)
        at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl$1StreamClosed.runInContext(ClientCallImpl.java:557)
        at io.grpc.internal.ContextRunnable.run(ContextRunnable.java:37)
        at io.grpc.internal.SerializingExecutor.run(SerializingExecutor.java:107)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)

This is dependencies at client:

<dependencies>
        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-netty</artifactId>
            <version>1.7.0</version>
        </dependency>

        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-protobuf</artifactId>
            <version>1.7.0</version>
        </dependency>

        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-stub</artifactId>
            <version>1.7.0</version>
        </dependency>

        <dependency>
            <groupId>io.netty</groupId>
            <artifactId>netty-tcnative-boringssl-static</artifactId>
            <version>2.0.6.Final</version>
        </dependency>

        <dependency>
            <groupId>com.lmax</groupId>
            <artifactId>disruptor</artifactId>
            <version>3.3.7</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-classic -->
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.3</version>
        </dependency>

</dependencies>

I'm using gRPC version 1.7.0.

Answer 1

Removing .usePlaintext(false) when creating channel will solve the problem.