WSAEWOULDBLOCK & WSAEINVAL

[Rick Martin]

While testing several new interfaces in 5.3 REV1, we have to Stop/Restart threads in order to get a connection to the receiving system (TCP/IP sockets over VPN).  

When the outbound thread is initially brought up, we get the WSAEWOULDBLOCK connect error followed by the WSAEINVAL connect error.  The thread waits for the timeout, but seems to never connect unless we bring the thread down and up; and in some cases have to bring other threads in the same process down in order for the outbound thread to connect to the receiving system.  

Is this a known problem?  Any known workarounds?  Anyone else experiencing the same thing?

Thanks, Rick

Topic

[Mark Perschbacher]

We have had some issues with establishing TCP/IP connections between Cloverleaf and foreign systems.  It sounds like this is an outbound thread, what are you using for protocol under Thread properties, and under PDL?

[Rick Martin]

Yep, it’s an outbound thread using PROTOCOL: pdl-tcpip and mlp_tcp.pdl.

Have you been able to do anything about your issues?

[Mark Perschbacher]

I have spent hours troubleshooting with our partners for the foreign systems, and truthfully, haven’t got very far.  The general observation is that some systems Cloverleaf seems to communicate well with, and others, not so well.  By turning on the EO logging, you can tell alot about what is happening connection-wise, but in most cases it has come down to we send an ORU, but never get the ACK back.  Sorry I don’t have any more useful suggestions.

[Jim Kosloskey]

Can I hazard a guess this/these is/are Windows based receiving systems?

I hazard this guess because these kinds of situations happen most often, in my experience, with Windows systems. It seems to me that many (maybe most) Windows programmers who program TCP/IP at the socket level are really unprepared for the challenge. This is complicated by Windows not being the best (in my opinion) environment to deploy mission critical TCP/IP based real time solutions.

All I can suggest is in my experience the problem has been with the receiving system and rarely with Cloverleaf. I generally prove that I have everything OK on my end (the Process log usually suffices for that) and challenge the other end to provide the same proof (they rarely can, but if they make the effort sometimes they magically correct the issue).

Jim Koloskey

email: jim.kosloskey@jim-kosloskey.com 29+ years Cloverleaf, 59 years IT - old fart.

[Mark Perschbacher]

Jim, in our environment, yes Cloverleaf is loaded on a Win2003 server.  The problem we are having is in the sending of ORU’s to a UNIX server.  What is really strange about the situation is that we also have an HL7 interface directly from our lab system, also a Win2X server, to this same UNIX box, and it works fine.  It does appear to be more of an OS problem than Cloverleaf related.

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