Message-ID: <4B4A6719.1020308@tlinx.org>
Date: Sun, 10 Jan 2010 15:47:37 -0800
From: Linda Walsh <cygwin AT tlinx DOT org>
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To: "cygwin AT cygwin DOT com" <cygwin AT cygwin DOT com>
Subject: odd network inconsistency tween 'win-secureCRT' & cygwin-(ssh)
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I'm trying to expand my networking horizons ...*cough*.

I won't claim I know what I'm doing, so try to keep that in mind...

I am trying to 'connect' (in various ways) from my win7-64(athenae)
box (on the ".sc" or "default" subnet) to a separate box on another 
subnet subnet (.hz subnet) through a SuSE-11.1 server(Ishtar) that
I'm still unsure is configured 100% correctly for what I want to do.  

In my setup, firewalls shouldn't be a source for interference (disabled).

I can use a windows-64 based app, "SecureCRT" and connect to the 
remote box (maya.hz), indicating (I think) that ARP, and TCP are being
forwarded through Ishtar.

My confusions come from:
1) maya.hz can ping athenae[.sc], but athenae can't ping maya.
I get:
92 bytes from 192.168.3.1: icmp_type=3 (Dest Unreachable) icmp_code=1
(192.168.3.1=Ishtar)..

So why would I get unreachable from one direction, but have it be
reachable from the other direction?  (Note, Ishtar can ping maya just
fine, so it's not that maya has pinging disabled).

2) Second confusion stems from "ssh" (in cygwin).  
It canNOT reach maya -- unlike the Winprog 'SecureCRT'.

-------

Why can a windows program reach it while the console SSH cannot?

Note, a "-v" on ssh shows the same messages I get back from ping.
(the Dest unreachable).

Does the console SSH version use ICMP to verify the connection
before attempting a TCP connection?  When I do a nslookup on the 
Windows client, I get proper address lookup:
/etc> nslookup maya
Server:  ishtar.sc.tlinx.org
Address:  192.168.3.1

Name:    maya.hz.tlinx.org
Address:  192.168.127.5
----

When I use wireshark to look at the traffic, SecureCRT connects to
address 192.168.127.5  .  So they are both trying to go to the same
location.  But I don't see the ICMP attempt for SecureCRT.  Maybe that's
the problem?


if ICMP works from maya.hz ->athenae.sc, why doesn't it work from
athena.sc->maya.hz?  My default route is set to 'ishtar' which is doing
the routing between the two subnets -- this would seem to be indicated by the
ICMP error response coming from ishtar.

Any ideas?  I know much of this is outside of cygwin-specificity, but 
it's only pertinent insomuch as the cygwin networking seems to be taking
a different route and the cygwin-based ssh doesn't seem to connect when
a non-cygwin, Win-64-based program does.

This is one of those icky situations where my problem spans multiple
areas/lists -- cygwin, suse, and maybe ssh...sigh.

Thanks for any ideas...
-linda


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