Erro de conexão SQL intermitente estranho, corrigido na reinicialização, volta após 3-5 dias (ASP.NET)

Por algum motivo, a cada 3-5 dias, nosso aplicativo da Web perde a capacidade de abrir uma conexão com o db com o seguinte erro: o estranho é que tudo o que precisamos fazer é reiniciar o contêiner (é um VPS) e ele é restaurado. para a funcionalidade normal. Alguns dias depois, isso acontece novamente. Alguém já teve esse problema? Eu notei muitos logons ANÔNIMOS no log de segurança no meio da noite do nosso servidor AD, o que é estranho, e também alguns de um IP em Amsterdã. Não sei como saber exatamente o que eles significam ou se está relacionado ou não.

Server Error in '/ntsb' Application.
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Data.SqlClient.SqlException: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)

Source Error:

Line 11:        
Line 12:        
Line 13:        dbConnection.Open()
Line 14:        
Line 15:        


Source File: C:\Inetpub\wwwroot\includes\connection.ascx    Line: 13

Stack Trace:

[SqlException (0x80131904): A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)]
   System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +248
   System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +245
   System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, SqlConnection owningObject) +475
   System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject) +260
   System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart) +2445449
   System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +2445144
   System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +354
   System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +703
   System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +54
   System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +2414696
   System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +92
   System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +1657
   System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +84
   System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +1645687
   System.Data.SqlClient.SqlConnection.Open() +258
   ASP.includes_connection_ascx.getConnection() in C:\Inetpub\wwwroot\includes\connection.ascx:13
   ASP.default_aspx.Page_Load(Object sender, EventArgs e) in C:\Inetpub\wwwroot\Default.aspx:16
   System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +25
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +42
   System.Web.UI.Control.OnLoad(EventArgs e) +132
   System.Web.UI.Control.LoadRecursive() +66
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2428


Version Information: Microsoft .NET Framework Version:2.0.50727.3053; ASP.NET Version:2.0.50727.3053 

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