Re: New details, Re: Troubleshooting Telnet connections that drop for no apparent reason -- HELP?

On 5/20/13 7:24 AM, Dan Kimmel wrote:

Read will block indefinitely as long as socket is in the correct
state. I'm suggesting the socket is not in the correct state. 5250
stream (and I think TN5250 merely extends 5250) will have turned the
state around after sending the readMDT command. 5250 is a synchronous
half duplex protocol. In other words the socket is no longer "open"
after the readMDT is sent.

ENQ's, ACK's and NAK's are there in Ethernet, IP, TCP communications
as well as TwinAx. The socket protocol hides it all from your
application. You should see them in a WireShark trace.

But that doesn't explain why it's only with one specific customer, and seems to happen at random.

Everywhere else, it sits there, blocking, without regard to whether the host is expecting data, and if something happens (i.e., anything I've tried to induce artificially, including varying off the device from WRKCFGSTS, ending the connection from WRKTCPSTS, or unplugging the Ethernet cable), it throws an exception, rather than returning an EOF.

--
JHHL