[Samba] Firewall piercing - The Specified network name is no longer available.

[JLB]

Hi all.

I'm trying to set up one of my Unix machines at home so I can access my
stuff there via SMB from the Internet at large (read: from Windows-using
clients').

I'm behind two NATting devices-- the lame-p Prestige DSL modem provided by
Sprint DSL (a.k.a. Earthlink?) and a more typical home DSL/cable gateway
device.

I've poked holes in BOTH of these devices on ports 137, 138, 139 AND 445.
Only port 139 actually responds to TCP connections (well, only port 139
accepts a telnet, even from localhost.

See:

--------------------------------------------------------------------------
-bash-2.05b# telnet localhost 137
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
telnet: connect to address 127.0.0.1: Connection refused
-bash-2.05b# telnet localhost 138
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
telnet: connect to address 127.0.0.1: Connection refused
-bash-2.05b# telnet localhost 139
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
^]
telnet> close
Connection closed.
-bash-2.05b# telnet localhost 445
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
telnet: connect to address 127.0.0.1: Connection refused
--------------------------------------------------------------------------

It should go without saying that this machine's Samba shares work
PERFECTLY WELL within the LAN. ;)

Now, from the outside, I can telnet to port 139 on the machine just fine,
through both NAT devices. However, when I go Start, Run,
\\x.y.z.a\sharename (where "x.y.z.a" is the IP address-- not the FQDN-- of
the machine), Windows vomits up this unhelpful message:


--------------------------------------------------
\\x.y.z.a\sharename
The specified network name is no longer available.
--------------------------------------------------

See:

http://jlb.twu.net/tmp/unhelpful.png

Any ideas? The client machine runs Windows 2000 Pro.

--
J. L. Blank, Systems Administrator, twu.net