Path: utzoo!mnetor!uunet!husc6!hao!oddjob!gargoyle!thisted
From: thisted@gargoyle.UChicago.EDU (Ronald A. Thisted)
Newsgroups: comp.unix.wizards
Subject: netstat tables
Message-ID: <829@gargoyle.UChicago.EDU>
Date: 17 Dec 87 15:37:37 GMT
Reply-To: thisted@galton.uchicago.edu (Ronald A. Thisted)
Distribution: na
Organization: Dept of Statistics, Univ of Chicago
Lines: 37
Keywords: netstat, nfs, ftp

When I ftp to a particular computer (chip) on our local net, and if I
send a file to that machine from my local machine, on exit from ftp I
find that I have added a permanent entry into the active connections table
produced by netstat, an example of which is

> Active connections
> Proto Recv-Q Send-Q  Local Address      Foreign Address    (state)
> ...
> tcp        0      0  galton.uch.1626    chip.uchic.20      FIN_WAIT_2

There are currently a dozen such lines, and they appear to extract a nontrivial
performance penalty, apparently through the agency of the nfs daemon.

I am no wizard, but I am hoping that someone can enlighten me as to
 1) what is going on
 2) whether I can manually remove (kill, close?) the offenders (short of
    reboot)
 3) whether there is risk of filling up a table of some sort (if I just ignore
    the problem)
 4) whether the apparent degradation in load could be due to this phenomenon
 5) whether the fault is likely to be local or remote
 6) what I might do to remedy the situation.

Some facts:  the local machine is a SUN-2/120 running bsd4.2, release 2.2,
and ftp version 4.10.  The remote machine is a dec-20 running tops-20 and a
version of ftp that has the label 5T(14).  The problem does not occur unless
my machine initiates ftp contact, and a file is sent to the remote.  The
problem does not occur in using ftp with other machines as remote; it also
does not occur when doing the ftp from another machine (say a vax) to chip.

Any clues would be most welcome.

Ronald Thisted
Department of Statistics
The University of Chicago
  thisted@galton.uchicago.edu
  ...ihnp4!gargoyle!galton!thisted