From 98f814297ee4fcdec23cc0641642c47d7b9138e7 Mon Sep 17 00:00:00 2001 From: James Newton-King Date: Wed, 21 Aug 2019 09:43:59 +1200 Subject: [PATCH] Add paragraph that Http1AndHttp2 is not supported without TLS (#13891) --- aspnetcore/grpc/troubleshoot.md | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/aspnetcore/grpc/troubleshoot.md b/aspnetcore/grpc/troubleshoot.md index bb94e02de5..63ab5e4475 100644 --- a/aspnetcore/grpc/troubleshoot.md +++ b/aspnetcore/grpc/troubleshoot.md @@ -5,7 +5,7 @@ description: Troubleshoot errors when using gRPC on .NET Core. monikerRange: '>= aspnetcore-3.0' ms.author: jamesnk ms.custom: mvc -ms.date: 08/12/2019 +ms.date: 08/17/2019 uid: grpc/troubleshoot --- # Troubleshoot gRPC on .NET Core @@ -79,6 +79,8 @@ public static IHostBuilder CreateHostBuilder(string[] args) => }); ``` +When an HTTP/2 endpoint is configured without TLS, the endpoint's [ListenOptions.Protocols](xref:fundamentals/servers/kestrel#listenoptionsprotocols) must be set to `HttpProtocols.Http2`. `HttpProtocols.Http1AndHttp2` can't be used because TLS is required to negotiate HTTP/2. Without TLS, all connections to the endpoint default to HTTP/1.1, and gRPC calls fail. + The gRPC client must also be configured to not use TLS. For more information, see [Call insecure gRPC services with .NET Core client](#call-insecure-grpc-services-with-net-core-client). > [!WARNING]