Subject: Re: Strange behavior connecting to non-listening TCP ports
To: Dave Huang <>
From: Jason Thorpe <>
List: current-users
Date: 02/21/2000 14:38:56
On Mon, 21 Feb 2000 15:55:35 -0600 (CST) 
 Dave Huang <> wrote:

 > With my previous kernel, NetBSD/alpha 1.4S from Feb 16, telnetting to a
 > port that didn't have anyone listening would (eventually) give me a
 > Connection timed out message, rather than Connection refused.

right, there was some RST rate-limiting code added, and the first rev
was buggy due to a bug in ratecheck().

 > I've now upgraded to 1.4T from Feb 18, and I get this:
 > yerfable ~> telnet localhost 1234
 > Trying
 > telnet: connect to address Connection refused
 > Trying
 > telnet: Unable to connect to remote host: Connection refused
 > with the first 3 lines printing immediately, and the last line printing
 > after an ~6 second pause. "telnet yefable 1234" works as expected though
 > (connection refused immediately).
 > So what's with the two attempts to connect to localhost, and why the
 > long pause? I don't have ipfilter in my kernel, and don't think I've
 > changed anything in my kernel config recently.

I'm not exactly sure thy the 6 second pause in the second case.  I'll
attempt to reproduce it here.

        -- Jason R. Thorpe <>