Timeout di connessione a MSSQL Server 2017 quando l'applicazione è in esecuzione su Linux

Di recente ho avviato un'applicazione Web ASP.NET Core (WebAPI) utilizzando Entity Framework Core per le comunicazioni del database e tutto è andato per il meglio purché stavo eseguendo l'applicazione sul mio laptop nel mio ambiente di sviluppo.

Per l'hosting dell'app Web e del database sto usando un server Ubuntu (16.04.3 LTS). Ho installato il server sql più recente (Microsoft SQL Server 2017 (RC2) - 14.0.900.75 (X64)) e posso collegarmi alla mia applicazione fino a quando l'applicazione è in esecuzione su Windows. Tuttavia, usando lo stesso codice e la stessa stringa di connessione su Ubuntu tutte le query sono appena scadute. Ottengo il seguente output (exception / stacktrace):

fail: Microsoft.AspNetCore.Server.Kestrel[13]
      Connection id "0HL6RV4D2F9I6": An unhandled exception was thrown by the application.
System.Data.SqlClient.SqlException: Timeout expired.  The timeout period elapsed prior to completion of the operation or the server is not responding. ---> System.ComponentModel.Win32Exception: Unknown error 258
   --- End of inner exception stack trace ---
   at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)
   at System.Data.SqlClient.TdsParserStateObject.ReadSniError(TdsParserStateObject stateObj, UInt32 error)
   at System.Data.SqlClient.TdsParserStateObject.ReadSniSyncOverAsync()
   at System.Data.SqlClient.TdsParserStateObject.TryReadNetworkPacket()
   at System.Data.SqlClient.TdsParserStateObject.TryPrepareBuffer()
   at System.Data.SqlClient.TdsParserStateObject.TryReadByteArray(Byte[] buff, Int32 offset, Int32 len, Int32& totalRead)
   at System.Data.SqlClient.TdsParserStateObject.TryReadChar(Char& value)
   at System.Data.SqlClient.TdsParser.TryReadPlpUnicodeCharsChunk(Char[] buff, Int32 offst, Int32 len, TdsParserStateObject stateObj, Int32& charsRead)
   at System.Data.SqlClient.TdsParser.TryReadPlpUnicodeChars(Char[]& buff, Int32 offst, Int32 len, TdsParserStateObject stateObj, Int32& totalCharsRead)
   at System.Data.SqlClient.TdsParser.TryReadSqlStringValue(SqlBuffer value, Byte type, Int32 length, Encoding encoding, Boolean isPlp, TdsParserStateObject stateObj)
   at System.Data.SqlClient.TdsParser.TryReadSqlValue(SqlBuffer value, SqlMetaDataPriv md, Int32 length, TdsParserStateObject stateObj)
   at System.Data.SqlClient.SqlDataReader.TryReadColumnInternal(Int32 i, Boolean readHeaderOnly)
   at System.Data.SqlClient.SqlDataReader.GetValues(Object[] values)
   at Microsoft.EntityFrameworkCore.Storage.Internal.UntypedRelationalValueBufferFactory.Create(DbDataReader dataReader)
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryingEnumerable.Enumerator.BufferlessMoveNext(Boolean buffer)
   at Microsoft.EntityFrameworkCore.Storage.Internal.SqlServerExecutionStrategy.Execute[TState,TResult](Func`2 operation, Func`2 verifySucceeded, TState state)
   at Microsoft.EntityFrameworkCore.Query.QueryMethodProvider.<_ShapedQuery>d__3`1.MoveNext()
   at System.Linq.Enumerable.First[TSource](IEnumerable`1 source)
   at lambda_method(Closure , QueryContext )
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.<>c__DisplayClass20_0`1.<CompileQueryCore>b__0(QueryContext qc)
   at System.Linq.Queryable.First[TSource](IQueryable`1 source, Expression`1 predicate)
   at Considition.WebAPI.Controllers.GameController.InitiateGame(String apikey) in /home/fredrik/WebApps/Considition/Considition.WebAPI/Controllers/GameController.cs:line 70
   at lambda_method(Closure , Object , Object[] )
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeActionMethodAsync>d__27.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeNextActionFilterAsync>d__25.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Rethrow(ActionExecutedContext context)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeNextResourceFilter>d__22.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Rethrow(ResourceExecutedContext context)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeAsync>d__20.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Builder.RouterMiddleware.<Invoke>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Cors.Infrastructure.CorsMiddleware.<Invoke>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Hosting.Internal.RequestServicesContainerMiddleware.<Invoke>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.Frame`1.<RequestProcessingAsync>d__2.MoveNext()
ClientConnectionId:19a604ef-758e-4797-8780-6b95dcbfdd17
Error Number:-2,State:0,Class:11
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[2]
      Request finished in 35515.1854ms 500

La riga nel mio codice in cui si verifica l'eccezione è:

var teamGameState = ctx.GeneratedGameStates.First(x => x.TeamId == teamId);

La tabella ha solo una voce e guardando Activity Monitor in SSMS, posso vedere che il sql tradotto è qualcosa di simile (SELEZIONA TOP 1 * DA ...) e che la query impiega 35 secondi.

Ho letto di altre persone che hanno problemi simili quando provo a connettermi a SQL Server da Linux con lo stesso codice che funzionava bene da Windows, ma non sono riuscito a trovare una soluzione.

Qualcun altro sta riscontrando questo problema e, soprattutto, qualcuno l'ha risolto?