Authentication failed because the remote party has closed the transport stream

Question

Hi,

We have created the one app service and we published the code into the app service.

We are trying to call the external Api through the app service, but we are getting an exception. Please check below are the details of Api which we are trying to consume.

Eg- On page load i m trying to consume the external api trough the Azure app service, but when i hit the page it is getting error like below.

Error:

SystSystem.IO.IOException: Authentication failed because the remote party has closed the transport stream. at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest) at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest) at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest) at System.Net.Security.SslState.ForceAuthentication(Boolean receiveFirst, Byte[] buffer, AsyncProtocolRequest asyncRequest, Boolean renegotiation) at System.Net.Security.SslState.ProcessAuthentication(LazyAsyncResult lazyResult) at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state) at System.Net.TlsStream.ProcessAuthentication(LazyAsyncResult result) at System.Net.TlsStream.Write(Byte[] buffer, Int32 offset, Int32 size) at System.Net.PooledStream.Write(Byte[] buffer, Int32 offset, Int32 size) at System.Net.ConnectStream.WriteHeaders(Boolean async)em.IO.IOException: Authentication failed because the remote party has closed the transport stream. at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest) at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest) at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest) at System.Net.Security.SslState.ForceAuthentication(Boolean receiveFirst, Byte[] buffer, AsyncProtocolRequest asyncRequest, Boolean renegotiation) at System.Net.Security.SslState.ProcessAuthentication(LazyAsyncResult lazyResult) at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state) at System.Net.TlsStream.ProcessAuthentication(LazyAsyncResult result) at System.Net.TlsStream.Write(Byte[] buffer, Int32 offset, Int32 size) at System.Net.PooledStream.Write(Byte[] buffer, Int32 offset, Int32 size) at System.Net.ConnectStream.WriteHeaders(Boolean async)

Answer 1

Hello @Ashish D like AgaveJoe said this is a known issue- to try resolving the authentication error when calling an external API from an Azure App Service:

Check the TLS version of the client and the server, and make sure they are compatible. Also check the target framework of the app service and update it to TLS 1.3 if needed. The following reference documentation explains the details: https://docs.microsoft.com/en-us/azure/app-service/configure-ssl-bindings#enforce-tls-1112.

Best,

Grace