UCX and dangling sockets

From: Gerald Marsh (gerald-_at_-cyfer-remove_this.demon.co.uk)
Date: 07/13/04 

Date: Tue, 13 Jul 2004 21:22:59 +0100

Aarrgghhhh!

A few times we've seen situations where a TCP connection attempts
fails with "address in use" - error 48, I think.

It usually occurs when attempting to start a Roboeda listener on port
5050 (Again, I think). I'm quite sure that we've seen the same effect
with other connecting software when they are not set up as services.

The symptoms are that the listener process dies with the address is
use error but, if we leave the thing about two hours, the process is
created ok. I haven't got the accounting record to hand but it exists
with a strange status of something like:
%SYSTEM-?-DEVMNTFOR, device mounted foreign

A TCPIP SHO DEVICE does not show any socket attached to the affected
port.

I know that the address referred to is a combination of IP address,
protocol and port so I wonder if that is why I cannot see it.

In desparation I tried the TCP extensions to SDA but that showed
nothing either.

All the timers I think could be involved are measured in seconds; the
longest I've seen is about 10 minutes.

I suspect the timeout is under program control but why can't I see the
BG device?

I think that MQueue has also been similarly afflicted in the past but
thankfully that hasn't happened for a long time.

If anyone has any ideas on how to decrease the timer or how to clear
the port, I would be very grateful. It is really annoying when you
cannot fix a problem for two hours!

Thank you in eager anticipation and keep the VMS flag a'flying!

Gerald.

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