出错页面是：http://bullvet.net/course/list/2018dongxibuhui/?sp=isfree-0,p-18,o-3d,promotion-5,teachway-1
异常信息：连接超时时间已到。在尝试使用预登录握手确认时超过了此超时时间。这可能是因为预登录握手失败或服务器未能及时响应。 尝试连接到此服务器时花费的持续时间是 - [Pre-Login] initialization=16；handshake=7002；
Source:.Net SqlClient Data Provider
StackTrace:
   在 System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   在 System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   在 System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
   在 System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   在 System.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry)
   在 System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry)
   在 System.Data.SqlClient.SqlConnection.Open()
   在 Kesion.DataBase.DBHelper.ExecuteDataset(String connectionString, CommandType commandType, String commandText, DbParameter[] commandParameters)
   在 Kesion.SqlDAL.DataFactory.GetDataTable(String sqlstr)
   在 Kesion.Cache.MyCache.GetConfigByDB(String key)
   在 Kesion.Cache.MyCache.GetCacheConfig(Int32 n)
   在 Kesion.APPCode.HttpModule.ReUrl_BeginRequest(Object sender, EventArgs e)
   在 System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
   在 System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)
   在 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

InnerException:
System.ComponentModel.Win32Exception (0x80004005): 等待的操作过时。