Dlink DSL router doesn't like FreeBSD

[John Mills]

Walter -

On Fri, 14 May 2004, Walter C. Pelissero wrote:

> My problem is that ssh and telnet don't work.  I get as far as the
> Password prompt, I type it in, and then ssh freezes for a couple of
> minutes until it probably goes in timeout and gives up.

Before we blame the router, a little more information would be good.

First, are you coming into your LAN from outside, or going outwards?

If it's an outgoing-connection problem, I would look into the firewall
setting of the FBSD box. Maybe you set didn't set it up to pass the ports
for outgoing telnet and ssh, or maybe you shut off the replies on those
same ports.

As for the timeout - many ssh setups will attempt to confirm the incoming 
connection, and many clients come from unconfirmable IP addresses. This 
usually involves a timeout of a few tens of seconds, but not terminating 
the connection. On the other hand, if you are discarding reply packets, I 
would expect the remote server to timeout awaiting your response to its 
acknowledgement.

Second, if incoming, does your DSL account have a static IP address? Does
your FBSD box have a static address within your LAN? You need these in
order to route to your [FBSD] server. Are you running 'sshd' and 'telnetd'
in the FBSD box to accept incoming connections?

Try plugging the WindowBox into another of the router's ports, then use
PuTTY to telnet and ssh into your FBSD box (using it's LAN address,
naturally). If that works, the problem is definitely the router, but
possibly a setup issue. Especially since telnet is also involved. (Many
people disable incoming telnet, for security reasons.)

When you have intra-LAN access working, look into port forwarding in the 
router's setup: you want incoming traffic from the ports used by ssh and 
(if you enable it) telnet to be sent to the LAN address of your FBSD box. 
Knowing what you are looking for may help you find it in the manuals. 
PuTTY's control panel to set up a connection shows you the default 
'telnet' and 'ssh' ports if you are in doubt.

My experience with the D-Link router has been outgoing and setting up a 
local WindowBox with a static IP (so it could server as a printer for the 
LAN).

Keep us posted.

Tschuess.

 - John Mills
   john.m.mills at alum.mit.edu