System.Net.Sockets.SocketException in Function App 2.0

Question

I have function app 2.0 with set of functions with service bus and http trigger.

After deploying to our Azure production environment, we started to see below exception logged in the app insight from our function app.

Exception Type : System.Net.Sockets.SocketException

Exception Message: The SSL connection could not be established, see inner exception. Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. An existing connection was forcibly closed by the remote host

We are clueless about this exception and was following the issue - https://github.com/dotnet/core/issues/1696 and not sure by adding DOTNET_SYSTEM_NET_HTTP_USESOCKETSHTTPHANDLER=false will solve this issue.

Below is the stack trace I find it in the exception which is not triggered by my code.

System.Net.Http.HttpRequestException:
   at System.Net.Http.ConnectHelper+<EstablishSslConnectionAsyncCore>d__5.MoveNext (System.Net.Http, Version=4.2.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Threading.Tasks.ValueTask`1.get_Result (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.ConfiguredValueTaskAwaitable`1+ConfiguredValueTaskAwaiter.GetResult (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Net.Http.HttpConnectionPool+<CreateConnectionAsync>d__44.MoveNext (System.Net.Http, Version=4.2.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Threading.Tasks.ValueTask`1.get_Result (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.ConfiguredValueTaskAwaitable`1+ConfiguredValueTaskAwaiter.GetResult (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Net.Http.HttpConnectionPool+<WaitForCreatedConnectionAsync>d__49.MoveNext (System.Net.Http, Version=4.2.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Threading.Tasks.ValueTask`1.get_Result (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.ConfiguredValueTaskAwaitable`1+ConfiguredValueTaskAwaiter.GetResult (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Net.Http.HttpConnectionPool+<SendWithRetryAsync>d__39.MoveNext (System.Net.Http, Version=4.2.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter.GetResult (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Net.Http.RedirectHandler+<SendAsync>d__4.MoveNext (System.Net.Http, Version=4.2.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter.GetResult (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Net.Http.DiagnosticsHandler+<SendAsync>d__2.MoveNext (System.Net.Http, Version=4.2.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
Inner exception System.IO.IOException handled at System.Net.Http.ConnectHelper+<EstablishSslConnectionAsyncCore>d__5.MoveNext:
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.ConfiguredValueTaskAwaitable`1+ConfiguredValueTaskAwaiter.GetResult (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Net.FixedSizeReader+<ReadPacketAsync>d__1.MoveNext (System.Net.Security, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Net.Security.SslState.ThrowIfExceptional (System.Net.Security, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Net.Security.SslState.InternalEndProcessAuthentication (System.Net.Security, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Net.Security.SslState.EndProcessAuthentication (System.Net.Security, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Net.Security.SslStream.EndAuthenticateAsClient (System.Net.Security, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Net.Security.SslStream+<>c.<AuthenticateAsClientAsync>b__47_1 (System.Net.Security, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
   at System.Threading.Tasks.TaskFactory`1.FromAsyncCoreLogic (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable+ConfiguredTaskAwaiter.GetResult (System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e)
   at System.Net.Http.ConnectHelper+<EstablishSslConnectionAsyncCore>d__5.MoveNext (System.Net.Http, Version=4.2.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a)
Inner exception System.Net.Sockets.SocketException handled at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw:

Could you add the code that's throwing the exception? Is it the Functions runtime connection used for the service bus trigger, or is there some other code in there that's causing this? The issue you're linking to is one on Ubuntu, which OS are you hosting your Function on? — rickvdbosch, Dec 12 '18 at 10:25
I don't see any code from my side which is causing this issue. — Prabhu Somasundaram, Dec 12 '18 at 16:57
The call stack shows usage of async/await but not handling its exceptions. What's the functionality of your Azure function? If it sends out requests to other web services, you need to handle exceptions properly, or they will bloat out like that. — Lex Li, Dec 12 '18 at 17:28
@LexLi : There is no functionality of calling the api from my code and it looks the exception is thrown internally from framework. — Prabhu Somasundaram, Dec 18 '18 at 04:17

score 1 · Answer 1 · answered Dec 18 '18 at 04:23

1

Thanks All. Issue has been resolved by adding this environment varaible - DOTNET_SYSTEM_NET_HTTP_USESOCKETSHTTPHANDLER=false as specified in this Issue https://github.com/dotnet/core/issues/1696 and not sure by adding

answered Dec 18 '18 at 04:23

Prabhu Somasundaram

21
3

System.Net.Sockets.SocketException in Function App 2.0

1 Answers1