【发布时间】：2019-06-23 05:14:03
【问题描述】：
我制作了一个插件来从我的 SCP:SL（游戏）服务器上收集玩家的数据并将其保存到 MySQL 数据库中。
当连接到位于我本地 VPS 之外的外部数据库时（如 freemysqlhosting），它可以完美运行。
我的本地 VPS 正在运行 10.1.37-MariaDB-0+deb9u1 Debian 9.6 MySQL Server 并使用最新的单声道版本。
当我尝试在本地（通过 localhost/127.0.0.1）连接到我的 MariaDB Linux MySQL 数据库时，问题就开始了。 在连接到数据库时，我遇到了两个不同的错误：
- 一个用于 localhost（应用程序没有崩溃），
- 一个用于 127.0.0.1（应用程序崩溃）
当主机被指定为“localhost”时，我收到此错误
Unhandled Exception:
MySql.Data.MySqlClient.MySqlException (0x80004005): Unable to connect to any of the specified MySQL hosts. ---> System.AggregateException: One or more errors occurred. ---> System.Net.Sockets.SocketException: An address incompatible with the requested protocol was used
at System.Net.Sockets.SocketAsyncResult.CheckIfThrowDelayedException () [0x00014] in <ac210d81537245bc838518cc8e845861>:0
at System.Net.Sockets.Socket.EndConnect (System.IAsyncResult asyncResult) [0x0002c] in <ac210d81537245bc838518cc8e845861>:0
at System.Net.Sockets.TcpClient.EndConnect (System.IAsyncResult asyncResult) [0x0000c] in <ac210d81537245bc838518cc8e845861>:0
at System.Threading.Tasks.TaskFactory`1[TResult].FromAsyncCoreLogic (System.IAsyncResult iar, System.Func`2[T,TResult] endFunction, System.Action`1[T] endAction, System.Threading.Tasks.Task`1[TResult] promise, System.Boolean requiresSynchronization) [0x00019] in <f2e6809acb14476a81f399aeb800f8f2>:0
--- End of inner exception stack trace ---
at System.Threading.Tasks.Task.ThrowIfExceptional (System.Boolean includeTaskCanceledExceptions) [0x00011] in <f2e6809acb14476a81f399aeb800f8f2>:0
at System.Threading.Tasks.Task.Wait (System.Int32 millisecondsTimeout, System.Threading.CancellationToken cancellationToken) [0x00043] in <f2e6809acb14476a81f399aeb800f8f2>:0
at System.Threading.Tasks.Task.Wait (System.Int32 millisecondsTimeout) [0x00000] in <f2e6809acb14476a81f399aeb800f8f2>:0
at MySql.Data.Common.StreamCreator.GetTcpStream (MySql.Data.MySqlClient.MySqlConnectionStringBuilder settings) [0x0001f] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at MySql.Data.Common.StreamCreator.GetStream (MySql.Data.MySqlClient.MySqlConnectionStringBuilder settings) [0x00021] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at MySql.Data.MySqlClient.NativeDriver.Open () [0x00007] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
---> (Inner Exception #0) System.Net.Sockets.SocketException (0x80004005): An address incompatible with the requested protocol was used
at System.Net.Sockets.SocketAsyncResult.CheckIfThrowDelayedException () [0x00014] in <ac210d81537245bc838518cc8e845861>:0
at System.Net.Sockets.Socket.EndConnect (System.IAsyncResult asyncResult) [0x0002c] in <ac210d81537245bc838518cc8e845861>:0
at System.Net.Sockets.TcpClient.EndConnect (System.IAsyncResult asyncResult) [0x0000c] in <ac210d81537245bc838518cc8e845861>:0
at System.Threading.Tasks.TaskFactory`1[TResult].FromAsyncCoreLogic (System.IAsyncResult iar, System.Func`2[T,TResult] endFunction, System.Action`1[T] endAction, System.Threading.Tasks.Task`1[TResult] promise, System.Boolean requiresSynchronization) [0x00019] in <f2e6809acb14476a81f399aeb800f8f2>:0 <---
at MySql.Data.MySqlClient.NativeDriver.Open () [0x00041] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at MySql.Data.MySqlClient.Driver.Open () [0x0000e] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at MySql.Data.MySqlClient.Driver.Create (MySql.Data.MySqlClient.MySqlConnectionStringBuilder settings) [0x0004e] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at MySql.Data.MySqlClient.MySqlPool.CreateNewPooledConnection () [0x00006] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at MySql.Data.MySqlClient.MySqlPool.GetPooledConnection () [0x0008a] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at MySql.Data.MySqlClient.MySqlPool.TryToGetDriver () [0x0003f] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at MySql.Data.MySqlClient.MySqlPool.GetConnection () [0x0001c] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at MySql.Data.MySqlClient.MySqlConnection.Open () [0x0016d] in <ffa6b95770be4daf8d8ae25ca059b16a>:0
at DataCollector.RoundEventHandler.<OnWaitingForPlayers>g__CheckIfTableExists|3_0 () [0x000db] in <8dda65d2174e4f2a8af95550bb525546>:0
at System.Threading.ThreadHelper.ThreadStart_Context (System.Object state) [0x00014] in <f2e6809acb14476a81f399aeb800f8f2>:0
at System.Threading.ExecutionContext.RunInternal (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) [0x00071] in <f2e6809acb14476a81f399aeb800f8f2>:0
at System.Threading.ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) [0x00000] in <f2e6809acb14476a81f399aeb800f8f2>:0
at System.Threading.ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state) [0x0002b] in <f2e6809acb14476a81f399aeb800f8f2>:0
at System.Threading.ThreadHelper.ThreadStart () [0x00008] in <f2e6809acb14476a81f399aeb800f8f2>:0
错误，当我将主机指定为“127.0.0.1”时看起来像这样（它太长了，所以我附上了它的粘贴箱）
这是我插件的c#mysql连接代码，我使用MySQLConnector v 8.0.13连接数据库：
MySqlConnectionStringBuilder connstr = new MySqlConnectionStringBuilder();
DatabaseConnInfo.dbhost = _plugin.GetConfigString("dc_dbhost");
DatabaseConnInfo.dbname = _plugin.GetConfigString("dc_dbname");
DatabaseConnInfo.dbuser = _plugin.GetConfigString("dc_dbuser");
DatabaseConnInfo.dbpass = _plugin.GetConfigString("dc_dbpass");
DatabaseConnInfo.dbport = (uint)_plugin.GetConfigInt("dc_dbport");
connstr.Server = DatabaseConnInfo.dbhost;
connstr.Database = DatabaseConnInfo.dbname;
connstr.UserID = DatabaseConnInfo.dbuser;
connstr.Password = DatabaseConnInfo.dbpass;
connstr.Port = DatabaseConnInfo.dbport;
_plugin.Info(connstr.ToString());
MySqlConnection conn = new MySqlConnection(connstr.ToString());
conn.Open();
string sql = "some sql statement";
MySqlCommand comm = new MySqlCommand(sql, conn);
conn.Close();
预期结果是与本地数据库建立有效连接，但由于错误而无法正常工作。
那些错误很奇怪，因为我可以轻松连接到外部数据库，本地连接似乎有问题，我不知道该怎么办。
【问题讨论】：
标签： c# mysql mysql-connector