An existing connection was forcibly closed by the

Question

I am working with a commercial application which is throwing a SocketException with the message,

An existing connection was forcibly closed by the remote host

This happens with a socket connection between client and server. The connection is alive and well, and heaps of data is being transferred, but it then becomes disconnected out of nowhere.

Has anybody seen this before? What could the causes be? I can kind of guess a few causes, but also is there any way to add more into this code to work out what the cause could be?

Any comments / ideas are welcome.

... The latest ...

I have some logging from some .NET tracing,

System.Net.Sockets Verbose: 0 : [8188] Socket#30180123::Send() DateTime=2010-04-07T20:49:48.6317500Z

System.Net.Sockets Error: 0 : [8188] Exception in the Socket#30180123::Send - An existing connection was forcibly closed by the remote host DateTime=2010-04-07T20:49:48.6317500Z 

System.Net.Sockets Verbose: 0 : [8188] Exiting Socket#30180123::Send() -> 0#0

Based on other parts of the logging I have seen the fact that it says '0#0' means a packet of 0 bytes length is being sent. But what does that really mean?

One of two possibilities is occuring, and I am not sure which,

1) The connection is being closed, but data is then being written to the socket, thus creating the exception above. The 0#0 simply means that nothing was sent because the socket was already closed.

2) The connection is still open, and a packet of zero bytes is being sent (i.e. the code has a bug) and the 0#0 means that a packet of zero bytes is trying to be sent.

What do you reckon? It might be inconclusive I guess, but perhaps someone else has seen this kind of thing?

Answer 1

I met this Exception ,when DateTime property of the class not getting the value .I Simply make it nullable DateTime and Found the solution .

public class PlanningBoardBO
    {
        ... Other Properties ...

        public DateTime? PickupDate { get; set; }

        ... Here changed DateTime to DateTime?
    }

Answer 2

This error occurred in my application with the CIP-protocol whenever I didn't Send or received data in less than 10s.

This was caused by the use of the forward open method. You can avoid this by working with an other method, or to install an update rate of less the 10s that maintain your forward-open-connection.

Answer 3

I've got this exception because of circular reference in entity.In entity that look like

public class Catalog
{
    public int Id { get; set; }
    public int ParentId { get; set; }
    public Catalog Parent { get; set; }
    public ICollection<Catalog> ChildCatalogs { get; set; }
}

I added [IgnoreDataMemberAttribute] to the Parent property. And that solved the problem.