Aspnetcore.docs: GrPC invalid http/2 connection preface

Created on 4 Jul 2019 · 14Comments · Source: dotnet/AspNetCore.Docs

Microsoft.AspNetCore.Server.Kestrel: Information: Connection id "0HLO001722806": HTTP/2 connection error.

Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2.Http2ConnectionErrorException: HTTP/2 connection error (PROTOCOL_ERROR): Invalid HTTP/2 connection preface.
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2.Http2Connection.ParsePreface(ReadOnlySequence1& buffer, SequencePosition& consumed, SequencePosition& examined) at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2.Http2Connection.TryReadPrefaceAsync() at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2.Http2Connection.ProcessRequestsAsyncTContext
Microsoft.AspNetCore.Server.Kestrel: Information: Connection id "0HLO001722807": HTTP/2 connection error.

Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2.Http2ConnectionErrorException: HTTP/2 connection error (PROTOCOL_ERROR): Invalid HTTP/2 connection preface.
at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2.Http2Connection.ParsePreface(ReadOnlySequence1& buffer, SequencePosition& consumed, SequencePosition& examined) at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2.Http2Connection.TryReadPrefaceAsync() at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2.Http2Connection.ProcessRequestsAsyncTContext
Microsoft.Hosting.Lifetime: Information: Application is shutting down...
EventSource Error: ERROR: Exception during construction of EventSource Microsoft-System-Net-Primitives: Incorrect function.
The program '[15348] GrPC.exe: Program Trace' has exited with code 0 (0x0).
The program '[15348] GrPC.exe' has exited with code -1073741510 (0xc000013a).

Document Details

⚠ Do not edit this section. It is required for docs.microsoft.com ➟ GitHub issue linking.

ID: 4e072aff-35c1-1fc2-3f94-97dc7a809414
Version Independent ID: 2f05b9da-0d50-ce84-d6af-332da7d9d625
Content: gRPC services with ASP.NET Core
Content Source: aspnetcore/grpc/aspnetcore.md
Product: aspnet-core
GitHub Login: @JunTaoLuo
Microsoft Alias: johluo

PU Source - Docs.ms

Source

hooseinsaid

Most helpful comment

Hi everyone

I think the issue here is a mis-match between the server and the client over whether to use HTTPS.

Grpc.Net.Client by default will use HTTPS:

    var httpClient = new HttpClient();
    // The port number(5001) must match the port of the gRPC server.
    httpClient.BaseAddress = new Uri("https://localhost:5001");
    var client = GrpcClient.Create<Greeter.GreeterClient>(httpClient);

To use Grpc.Net.Client without TLS you must set an app context switch and change the base address to start with http:

    AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);
    var httpClient = new HttpClient();
    // The port number(5001) must match the port of the gRPC server.
    httpClient.BaseAddress = new Uri("http://localhost:5001");
    var client = GrpcClient.Create<Greeter.GreeterClient>(httpClient);

JamesNK on 30 Jul 2019

🎉5

All 14 comments

dotnet --version ?

Rick-Anderson on 4 Jul 2019

it is 3.0
3.0.100-preview6-012264
<PropertyGroup> <TargetFramework>netcoreapp3.0</TargetFramework> </PropertyGroup>

hooseinsaid on 4 Jul 2019

I bumped into the same issue with the Greeter sample and the fallback was to bypass Grpc.Net.Client and use just Grpc.Core.
Hope this helps!

iulianaciura on 10 Jul 2019

I am facing the exact same situation

strykerin on 22 Jul 2019

I bumped into the same issue with the Greeter sample and the fallback was to bypass Grpc.Net.Client and use just Grpc.Core.
Hope this helps!

Thanks a lot, I solved the problem in this way.

zxyao145 on 24 Jul 2019

👍1

I bumped into the same issue with the Greeter sample and the fallback was to bypass Grpc.Net.Client and use just Grpc.Core.
Hope this helps!

It helped. Thanks.

This is an issue with preview7 as well. Any plan to fix this in final release?

mustakimali on 30 Jul 2019

I bumped into the same issue with the Greeter sample and the fallback was to bypass Grpc.Net.Client and use just Grpc.Core.
Hope this helps!

Thank you! This solved my problem

strykerin on 30 Jul 2019

I bumped into the same issue with the Greeter sample and the fallback was to bypass Grpc.Net.Client and use just Grpc.Core.
Hope this helps!

@iulianaciura could you add more context for how you used core to get around this? Maybe a example? Thanks.

MambaDev on 30 Jul 2019

Hi everyone

I think the issue here is a mis-match between the server and the client over whether to use HTTPS.

Grpc.Net.Client by default will use HTTPS:

    var httpClient = new HttpClient();
    // The port number(5001) must match the port of the gRPC server.
    httpClient.BaseAddress = new Uri("https://localhost:5001");
    var client = GrpcClient.Create<Greeter.GreeterClient>(httpClient);

To use Grpc.Net.Client without TLS you must set an app context switch and change the base address to start with http:

    AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);
    var httpClient = new HttpClient();
    // The port number(5001) must match the port of the gRPC server.
    httpClient.BaseAddress = new Uri("http://localhost:5001");
    var client = GrpcClient.Create<Greeter.GreeterClient>(httpClient);

JamesNK on 30 Jul 2019

🎉5

When you run the gRPC server, what is the console output when it starts?

For example:

C:\Development\Source\AspNetCore.Docs\aspnetcore\tutorials\grpc\grpc-start\sample\GrpcGreeter [jamesnk/grpc-sample-fix ≡]> dotnet run
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: https://localhost:5001
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Development
info: Microsoft.Hosting.Lifetime[0]
      Content root path: C:\Development\Source\AspNetCore.Docs\aspnetcore\tutorials\grpc\grpc-start\sample\GrpcGreeter

Now listening on: https://localhost:5001 indicates that you want to use HTTPS to call the server.

JamesNK on 30 Jul 2019

Hi everyone

I think the issue here is a mis-match between the server and the client over whether to use HTTPS.

Grpc.Net.Client by default will use HTTPS:
    var httpClient = new HttpClient();
    // The port number(5001) must match the port of the gRPC server.
    httpClient.BaseAddress = new Uri("https://localhost:5001");
    var client = GrpcClient.Create<Greeter.GreeterClient>(httpClient);
To use Grpc.Net.Client without TLS you must set an app context switch and change the base address to start with http:
    AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);
    var httpClient = new HttpClient();
    // The port number(5001) must match the port of the gRPC server.
    httpClient.BaseAddress = new Uri("http://localhost:5001");
    var client = GrpcClient.Create<Greeter.GreeterClient>(httpClient);

This worked great for me @JamesNK thank you. Is this expected to be a flag later on or are we expected to be adjusting the context in the future if we require http?

Thanks.

MambaDev on 31 Jul 2019

👍1

I don't know of plans to make HTTP/2 without TLS officially supported.

Disclaimer that you should only use HTTP in development. Always use HTTPS for real data over the internet.

JamesNK on 31 Jul 2019

As no browser supports HTTP/2 without TLS encryption is defacto mandatory. You're in uncharted and unsupported scenarios. This will not be exposed as a flag, and will remain only available as an AppContext switch which we will remove at some point.