1.问题还原：
The service does not automatically connect, free after a period of time, the first call will appear the following error, next to normal.
The program is based on.Net Framework, The Grpc.Core version is 1.4.1.
Grpc.Core.RpcException: Status(StatusCode=Unavailable, Detail="Endpoint read failed")
在 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
在 Grpc.Core.Internal.AsyncCall`2.UnaryCall(TRequest msg)
在 Grpc.Core.Calls.BlockingUnaryCall[TRequest,TResponse](CallInvocationDetails`2 call, TRequest req)
在 Grpc.Core.DefaultCallInvoker.BlockingUnaryCall[TRequest,TResponse](Method`2 method, String host, CallOptions options, TRequest request)
在 Grpc.Core.Internal.InterceptingCallInvoker.BlockingUnaryCall[TRequest,TResponse](Method`2 method, String host, CallOptions options, TRequest request)
The document says I can try again. Isn't this supposed to be implemented internally in grpc.core?
使用新版本试试：This issue looks stale and it is not clear what the intent was. Also 1.4.1 is pretty old, feel free to try with 1.12.0 and if you are still seeing a problem, file this as a new issue.