Subject: Routing and tunneling; docs for /dev/tun0
To: None <current-users@NetBSD.ORG>
From: maillist alias for CWW <>
List: current-users
Date: 12/14/1996 08:09:57
I have a trial ASDN installation at my home. It gives me a white box
on the wall conencted to my home system by an  ethernet connection  and to the
world ( 1.5Mbits from the world inward, 
90kbits outward ). It has a fixed ip number and apparently won't
route any other number in to my box. But it's still FUN....

There are a couple of problems:

1) the ip number has no symbolic name recognized by any DNS or routing 
tables. This means that it is hard to get mail at home directly, and
connections to sites that do reverse ip lookups reject connections.
And not having a Purdue ip number means I'm locked out of certain
services like News and some data bases.

2) I used to use PPP with a fixed ip number for this box, and this had
an official name. Routing, DNS, Mail, etc all worked under the old slow
system. I'd like to get this functionality back ( with better speed
of course )

There are of course workarounds to most of these problems. However, I'm 
compulsive enough to want a global solution.

I have control of a machine in office at work ( running Netbsd-current also).

Here's the functionality I would like:

Office machine = ROLLE
Home machine = ASDN
Old home IP = HOPF2

I'd like to use the fact that I can make an tcpip connection from
ROLLE <--> ASDN  to route traffic for HOPF2  to ASDN.

If I just alias the ethernet port on ASDN to the old HOPF2 ip number
I cannot get the gateway upstream to ASDN to route packets for 

But it seems like there should be a combination of IP-aliasing
and IP-tunneling ( IP within IP) that would do what I want.
However, I could find no documentation for the /dev/tun0 device
and I wasn't sure what the tunneling mentioned in the
MROUTED man page was all about.

In my old system, PPP over the phone line handled this. However, I can't get
ppp to work over an TCP link. So I would appreciate any suggestions.

Clarence Wilkerson