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Hello! Can you suggest what might be the source (And remedy) for this error that occurs on certain PCs in our organization, but not others?
System.Exception: Unable to establish connection because Rpc error 'Internal': Status(StatusCode="Internal", Detail="Error starting gRPC call. HttpRequestException: Requesting HTTP version 2.0 with version policy RequestVersionExact while unable to establish HTTP/2 connection.", DebugException="System.Net.Http.HttpRequestException: Requesting HTTP version 2.0 with version policy RequestVersionExact while unable to establish HTTP/2 connection.")
The only relevant related answer I found online was:
But it is a bit old, and perhaps a lot has changed since then. We are using .NET 8 and Grpc.Net.Client 2.66.0. We are using http:// (not https://)
On the client side, the only thing we are doing before establishing connection is:
AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);
On the server side, this is the relevant server initialization (C++)
ServerBuilder builder;
builder.AddListeningPort(server_address, grpc::InsecureServerCredentials());
// ... continue with registering service, building, and starting
Any help you can provide in troubleshooting this issue would be appreciated. Thanks!
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does your network support http2? not only does the client O/S and server O/S need to support, but any firewall or proxies between must also support http2.
That's a reasonable question, thanks for the reply. Is there a diagnostic we can perform to check this? The closest I could find to a diagnostic online is here:
https://stackoverflow.com/questions/54091567/how-to-check-if-a-website-has-http-2-protocol-support
I missed you are using http. http2, and thus gRPC, only supports ssl connections (https).
'http2 only supports ssl connections (https)'
^^ now I'm more confused.
The configuration described above is working on most PCs in our organization, and the client code connects using:
AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);
// open channel to gRPC control of LR
ControlChannel = GrpcChannel.ForAddress("http://" + address + ":" + channelType.GetPort());
So, we are specifying http:// in our connection string...
Help me out, I'm obviously missing something here, and I'm interested in learning what's going on.
And, ultimately, interested in figuring out why most PCs work, but a few give the error above.
And, to follow up, when I change the C# connection code in the previous comment to use "https://" instead of "http://" and run the client on a PC that has always worked, I get this exception (hence why we've been using "http://" in our connection string):
Rpc error 'Internal': Status(StatusCode="Internal", Detail="Error starting gRPC call. HttpRequestException: The SSL connection could not be established, see inner exception. AuthenticationException: Cannot determine the frame size or a corrupted frame was received.", DebugException="System.Net.Http.HttpRequestException: The SSL connection could not be established, see inner exception.")
Any ideas on what's going on?
(btw, at this point in the apps lifecycle, we're not concerned about a secure network connection.)
(removed duplicate comment)
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so i have run into a similar situation, i also have .NET 8 and Grpc.Net.Client 2.66.0
I don't know if it makes a difference, but the error gets triggered for me when I make a Firebase call.
have you been able to track down the issue?