OpenAsync throws "System.Net.Sockets.SocketException: Broken pipe"

Sometimes i’m receiving SocketException when calling _con.OpenAsync(cancellationToken).

Follow the stack:

MySql.Data.MySqlClient.MySqlException: Unable to connect to any of the specified MySQL hosts. ---> System.Net.Sockets.SocketException: Broken pipe
   at MySql.Data.SocketAwaitable.GetResult()
   at MySql.Data.Protocol.Serialization.SocketByteHandler.<DoWriteBytesAsync>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 System.Threading.Tasks.ValueTask`1.get_Result()
   at MySql.Data.ValueTaskExtensions.ContinueWith[T,TResult](ValueTask`1 valueTask, Func`2 continuation)
   at MySql.Data.Protocol.Serialization.ProtocolUtility.WritePacketAsync(IByteHandler byteHandler, Int32 sequenceNumber, ArraySegment`1 contents, IOBehavior ioBehavior)
   at MySql.Data.Protocol.Serialization.ProtocolUtility.WritePayloadAsync(IByteHandler byteHandler, Func`1 getNextSequenceNumber, ArraySegment`1 payload, IOBehavior ioBehavior)
   at MySql.Data.Serialization.MySqlSession.TryAsync[TArg](Func`3 func, TArg arg, IOBehavior ioBehavior, CancellationToken cancellationToken)
   at MySql.Data.Serialization.MySqlSession.SendAsync(PayloadData payload, IOBehavior ioBehavior, CancellationToken cancellationToken)
   at MySql.Data.Serialization.MySqlSession.<TryPingAsync>d__24.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 MySql.Data.MySqlClient.ConnectionPool.<GetSessionAsync>d__0.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 MySql.Data.MySqlClient.MySqlConnection.<CreateSessionAsync>d__57.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 MySql.Data.MySqlClient.MySqlConnection.<OpenAsync>d__11.MoveNext()
   --- End of inner exception stack trace ---
   at MySql.Data.MySqlClient.MySqlConnection.<OpenAsync>d__11.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)

Maybe await SendAsync(PingPayload.Create(), ioBehavior, cancellationToken).ConfigureAwait(false); should be inside try catch to?

https://github.com/mysql-net/MySqlConnector/blob/master/src/MySqlConnector/Serialization/MySqlSession.cs#L141

[caleblloyd]

Broken pipe typically occurs either when you either unplug a network cable or encounter a NAT timeout. This happens because the server has closed the connection and sent a TCP FIN packet, but the client never got the FIN packet.

Since the client still thinks the connection is open, it continues the TCP conversation with the server from where it left off. The server has closed the connection already though, so it sends a RST packet. This causes a broken pipe exception.

It’s most likely NAT timeout or your network is going away and then coming back.

[naughtyGitCat]

we do not use nat, but physical host with static ip , the latest version does not fix too

mysql conn string is

    "MySQL": {
      "ReadWriteURI": "server=XXXXXX;port=3306;user=XXXXX;password=XXXXX;database=XXXXX",
      "ReadOnlyURI": "server=YYYYY;port=3306;user=YYYY;password=YYYY;database=YYYY;DefaultCommandTimeout=188;SslMode=None;MaximumPoolsize=1588;MinimumPoolSize=8;ConnectionReset=false;ConnectionIdlePingTime=2;ConnectionIdleTimeout=88"
    },

@caleblloyd