>Good point Richard.  I do see the session being terminated on the server,
>here is the log entry:
>
>07/28/01   12:50:37      ANR0480W Session 56995 for node MDBACK0.BTV.IBM.COM 
>(AIX)
>                         terminated - connection with client severed.

Matt - Good, thanks for that added piece of the puzzle...

Both your client and server are reporting interruption of the session.
If indeed neither initiated the termination, it suggests a problem with
network hardware breaking the TCP/IP session.  You may have other incidental
ongoing communications between the client and server systems which produce
logs that you may inspect.  Otherwise, use something like the attached csh
script to ping from one system to the other at intervals and log the results,
for overnight inspection.  Perhaps your network people are already aware of
instabilities or outages underlying this problem.

  Richard Sims, BU


#!/usr/bin/csh -f
#
# ping-loop -- to periodically ping an IP address and log the results.
#
# INVOCATION:  - Adjust governing definitions as needed.
#              - Execute by name:  'ping-loop'
#
# HISTORY:
#
#     1999/08/18  Written by Richard Sims
#

#__________________________Governing definitions_____________________________
set ipaddr = "111.222.333.444";         # The IP address to ping.
set sleep_secs = 9;                     # How long to wait between loop 
intervals.
set hostname = `/usr/bin/hostname`;
set logdir = "/var/tmp";
set logfile = "$logdir/$hostname";

#__________________________Preliminaries_____________________________________
# Create the log directory if it doesn't exist:
if (! -d $logdir) then
   /usr/bin/mkdir -p $logdir;
   if ($status) then
      echo "*** Error - could not mkdir $logdir.  Quitting.";
      exit 1;
   endif
   #echo "Successfully created directory $logdir.";
   /usr/bin/chmod g=rwx $logdir;        # Allow group administration.
endif

#__________________________Endless monitoring loop_____________________________
set prev_yyyymmdd = "";                 # Init to null string, tested below.
while (1)
   set yyyymmdd_hhmmss = `/usr/bin/date +"%Y%m%d %T"`;
   set yyyymmdd = $yyyymmdd_hhmmss[1];

   # If a day transition, cut off the previous day's log:
   if (($prev_yyyymmdd != "")  &&  ($yyyymmdd != $prev_yyyymmdd))  
/etc.local/cut-off-file $logfile;

   echo "================" $yyyymmdd_hhmmss "Pinging $ipaddr from $hostname 
================" >> $logfile;
   # Ping once.  Allow result to show up in log.
   /usr/sbin/ping  -c 1  $ipaddr >> $logfile;
   #if ($status == 1) then
   #   echo `/usr/bin/date +"%Y%m%d %T"` "Ping of $ipaddr failed";
   #endif
   set prev_yyyymmdd = $yyyymmdd;
   /usr/bin/sleep $sleep_secs;
end