System.Net.Internals.SocketExceptionFactory+ExtendedSocketException

Question

Hi,

The following exception throw occasionally when accessing a table, what I missed?

Usage.Get_Info: System.Net.Internals.SocketExceptionFactory+ExtendedSocketException (FFFFFFFF, 0xFFFDFFFE): Unknown socket error
at System.Net.Dns.GetHostEntryOrAddressesCore(String hostName, Boolean justAddresses, AddressFamily addressFamily, ValueStopwatch stopwatch)
at System.Net.Dns.GetHostAddresses(String hostNameOrAddress, AddressFamily family)
at Npgsql.Internal.NpgsqlConnector.Connect(NpgsqlTimeout timeout)
at Npgsql.Internal.NpgsqlConnector.RawOpen(SslMode sslMode, NpgsqlTimeout timeout, Boolean async, CancellationToken cancellationToken, Boolean isFirstAttempt)
at Npgsql.Internal.NpgsqlConnector.<Open>g__OpenCore|195_1(NpgsqlConnector conn, SslMode sslMode, NpgsqlTimeout timeout, Boolean async, CancellationToken cancellationToken, Boolean isFirstAttempt)
at Npgsql.Internal.NpgsqlConnector.Open(NpgsqlTimeout timeout, Boolean async, CancellationToken cancellationToken)
at Npgsql.ConnectorPool.OpenNewConnector(NpgsqlConnection conn, NpgsqlTimeout timeout, Boolean async, CancellationToken cancellationToken)
at Npgsql.ConnectorPool.<Get>g__RentAsync|28_0(NpgsqlConnection conn, NpgsqlTimeout timeout, Boolean async, CancellationToken cancellationToken)
at Npgsql.NpgsqlConnection.<Open>g__OpenAsync|45_0(Boolean async, CancellationToken cancellationToken)
at Npgsql.NpgsqlConnection.Open()
at Dapper.SqlMapper.ExecuteCommand(IDbConnection cnn, CommandDefinition& command, Action2 paramReader) at Dapper.SqlMapper.ExecuteImpl(IDbConnection cnn, CommandDefinition& command) at Dapper.SqlMapper.Execute(IDbConnection cnn, String sql, Object param, IDbTransaction transaction, Nullable1 commandTimeout, Nullable`1 commandType)

C# Code:

                   using (NpgsqlConnection conn = new NpgsqlConnection(Models.AppSettings.PG_SQL.Connection_String))  
                    {  
                        try  
                        {  
                              
  
                            using (var dr = conn.ExecuteReader(sql, new  
                            {  
                                ICCID = iccid  
                            }))  
                            {  
                                if (dr.Read())  
                                {  
                                    .....  
                                   ......  
                                }  
                            }  
                        }  
                        catch (Exception e)  
                        {  
                            Helper.SaveLogAsync("Usage.Get_Info: " + e.ToString(), Models.Errs.ErrType.Err);  
                        }  
                        finally { }  
                    }