IT14958: Intermittent message delivery fails in a managed .NET client application with SSL enabled

APAR status

• Closed as program error.

Error description

• Description: SSL connections using the IBM MQ .NET client
  libraries fail intermittently during large message transfer with
  2195 MQRC_UNEXPECTED_ERROR during an MQPUT.
  
  In a trace, the following text appears:
  
  System.IO.IOException: Unable to write data to the transport
  connection: A non-blocking socket operation could not be
  completed immediately. ---> System.Net.Sockets.SocketException:
  A non-blocking socket operation could not be completed
  immediately
     at System.Net.Sockets.Socket.Send(Byte[] buffer, Int32
  offset, Int32 size, SocketFlags socketFlags)
     at System.Net.Sockets.NetworkStream.Write(Byte[] buffer,
  Int32 offset, Int32 size)
     --- End of inner exception stack trace ---
     at System.Net.Sockets.NetworkStream.Write(Byte[] buffer,
  Int32 offset, Int32 size)
     at System.Net.Security._SslStream.StartWriting(Byte[] buffer,
  Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest)
     at System.Net.Security._SslStream.ProcessWrite(Byte[] buffer,
  Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest)
     at System.Net.Security.SslStream.Write(Byte[] buffer, Int32
  offset, Int32 count)
     at IBM.WMQ.Nmqi.MQEncryptedSocket.Write(Byte[] buffer, Int32
  offset, Int32 length)
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  IBM MQ .NET Client applications using SSL connections
  
  
  Platforms affected:
  Windows
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  The MQ .NET classes failed to correctly handle a SocketException
  with error code 10035 (WSAEWOULDBLOCK) being returned from the
  .NET runtime.
  
  This failure to handle the error condition could result in an
  incomplete sequence of bytes being written over the secure
  socket. This invalid transmission caused the transport layer to
  request a reset of the connection, which the client reports as a
  2195 MQRC_UNEXPECTED_ERROR.
  
  If running directly from MS Visual Studio, the following
  exceptions also appear (among others) in the debug output:
  A first chance exception of type
  'System.Net.Sockets.SocketException' occurred in System.dll
  A first chance exception of type 'System.IO.IOException'
  occurred in System.dll
  A first chance exception of type 'System.IO.IOException'
  occurred in System.dll
  A first chance exception of type 'System.IO.IOException'
  occurred in amqmdnet.dll
  A first chance exception of type 'IBM.WMQ.Nmqi.NmqiException'
  occurred in amqmdnet.dll
  

Problem conclusion

• The MQ .NET classes have been updated to correctly handle the
  WSAEWOULDBLOCK error code from the .NET runtime when writing
  data to a secure socket.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.6
  
  The latest available maintenance can be obtained from
  'WebSphere MQ Recommended Fixes'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'WebSphere MQ
  Planned Maintenance Release Dates'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
  ---------------------------------------------------------------
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  WMQ BASE MULTIP

• Fixed component ID

  5724H7251

Applicable component levels

• R800 PSY

     UP