The Amateur Packet Radio Gateways
FAQ
Version 2.3, December 29, 1999
This is a short FAQ answering some questions about the Internet/AMPRnet
gateways. If you have any suggestions or comments about the content, please
email them to me at one of the following addresses.
James Fuller
Internet: n7vmr@fuller.net
AMPRnet: n7vmr@n7vmr.ampr.org
I'd like to thank Warren Toomy VK1XWT, Brian Kantor WB6CYT, Tony Querubin
AH6BW and Mike Gallaher WA2HEE for contributions to this FAQ, and everybody
who made suggestions on how to improve it.
Contents
The missing contents of this FAQ are:
-
Information on the converse servers and the mailing list.
-
Running a gateway without NOS, i.e with FreeBSD, Linux or another system.
You can check out the Linux
Ham Howto guide for Linux information.
-
Anything else We've forgotten.
The contents of this FAQ are:
Not all of these sections are complete as yet. If you can write/complete
a section, please do so and send it to me!
What's a wormhole? What's a gateway?
What's an Internet/AMPRnet gateway?
A wormhole is just a two-way ``data pipe'', say a phone line, that can
accept packets on one end, and spits them out at the other end. There is
only one possible destination. It is like an AX.25 digipeater, and in fact
many wormholes are fashioned to look just like one.
A wormhole doesn't know or care what is in the packets; in particular,
it doesn't do any routing. To use a wormhole, you have to know where its
input port is so you can send your packets through it (as if it were a
digipeater), and what stations are at the other end, so you can address
packets to them.
A gateway, on the other hand, takes incoming packets, and makes a decision
about how to forward on the packet, according to the details in the packet.
It may be able to pass the packet directly to the destination, or it sends
the packets to another gateway for further forwarding. This forwarding
is transparent to users of IP encap gateways - they just specify the destination
IP address and the gateway system takes care of the rest.
Ok, so how does this relate to an Internet/AMPRnet gateway? An Internet/AMPRnet
gateway routes AMPRnet packets between areas that are far apart, by using
the Internet as the medium. Packets are passed by first wrapping them (also
known as `encapsulation') in an IP packet, sending them to a distant gateway,
and unwrapping them there. This allows real-time long-distance TCP/IP communications.
This method of encapsulation can also be used as a wormhole for AX.25 and
NETROM communications.
How do I set a gateway up?
First you need a place which has an Internet connection. Next you need
to get permission to put amateur equipment (rig, antenna, PC) in, and then
you need to get permission to connect the PC to the Internet. Getting these
permissions is very dependent on your specific location, who you know and
the rules there etc. If you are unsure about things, other people who have
set up a gateway may be able to help you. See the next section for information
about how to get into contact with them.
If you can get a PC, rig and antenna in, and an Internet connection,
you now need to set up the gateway software. Information about doing this
can be obtained via anonymous ftp from the following machine:
ftp.fuller.net 206.155.74.126
n7vmr.ampr.org 44.82.64.236
Anonymous ftp to ftp.fuller.net, cd to hamradio/gateways, and have a look
around. Information about setting up a gateway can be found in the following
files:
-
newgate.txt
-
-- Setting up an Internet/Amprnet gateway, ASCII version
-
newgate.ps
-
-- PostScript version
-
newgate.zip
-
-- Word for Windows version
-
newgate.tex
-
-- LaTeX version
Remember to use binary mode for the newgate.ps and newgate.zip files.
Is there a mailing list for gateway
discussion?
Yes, if you are intending on setting up a gateway, or you are already doing
so, you should the mailing list. This way, you will learn of changes
to the other gateways. To join, send an email to gateways-owner@cows.net
, with "subscribe gateways [you@your.doman]" in the body of your message.
When you have subscribed, you can mail articles to the list by sending
them to gateways@cows.net. Currently, over 300 people are on the mailing
list, and most are willing to help new gateway administrators.
Who else is running a gateway?
In order to get your gateway working, you need to install encapsulated
routes to other gateways so your packets will get wrapped and sent to the
correct destination for unwrapping.
Information on who else is running a gateway, what their setup is, email
contact addresses, and the routing lines you should use, is available.
This file is the most up to date information available about the set of
gateways worldwide. It contains a timestamp so you know how old it is.
To get this file, Email n7vmr@fuller.net
for details.
Is there information about the
gateways with only AMPRnet stuff that I can distribute to the local users?
The file `resource'
on ftp.fuller.net in the hamradio/gateways directory contains information
about many machines (not just gateways) that can be accessed through the
gateways, and what services the machines provide. The file contains only
AMPRnet information (and no Internet information), and so is ideal for
distributing to your local AMPRnetters.
Unfortunately, this file is not kept up to date at all, so it is not
really that useful.
How do I update the gateways
file?
See the information on updating
your Gateways entry on fuller.net.
Do I have to manually extract
the routes from the gateways file?
No, as fuller.net changes the `gateways' file, she also creates another
file called `encap.txt', which contains only the NOS route commands from
the `gateways' file. You can ftp this file, and source it under NOS to
put in the new routes.
** N.B Remember that your own encap routes are in the file! If you just
source the file, you will destroy your own local routes. To prevent this:
a) Edit out your own encap lines, either manually or with a program
like grep, or
b) Source encap.txt from your autoexec.net, and THEN set up your local
routes; these should override the ones in encap.txt.
If you don't like to manually ftp this file from minnie, you can email
James Fuller n7vmr@fuller.net
and be put on a mailing list. As `encap.txt' is created, the new version
will be emailed to you with the subject line `Update: ENCAP.TXT'.
Are there maps showing where
the gateways are?
Yes, these can get obtained via anonymous
ftp from ftp.ucsd.edu, directory /hamradio/packet/gw in the following
formats:
-
gwmaps-ps.tar.Z
-
-- PostScript
-
gwmaps-hppcl.tar.Z
-
-- HP-PCL format
The maps depict the UUNet mail-only gateways as well as the IP routing
gateways.
My gateway locks up. How do
I fix this?
Good question. There are several solutions to this, in increasing order
of ruthlessness.
-
Don't run certain servers that lock the system up. The converse server
is a known problem, as is the domain name server.
-
In many cases, the machine is still running NOS, but you just can't get
in. You might try exiting NOS at periodic intervals, which will free up
the used memory, and restart things. This can be done in software using
the `at' command, e.g
at 0001 exit
at 0600 exit
at 1200 exit
at 1800 exit
which will reboot NOS every 6 hours. However, Rogan Clements notes:
The `at' command does not work if you have the keyboard locked
with the `lock' command. So I put an
at now+(0ne min before reboot) (keyboard password)
and the problem is solved.
Alternatively, you can send a remote reboot packet from another machine.
Check out the NOS documentation (such that it is) for more information.
If you have a Unix machine around and you'd rather use that, source to
a reboot program can be obtained from minnie in the hamradio/gateways directory,
file `unix-remote.c'.
-
If the machine locks up hard, you might like to try the hardware developed
by Tony Querubin, which monitors the RS-232 port, and `hits' the reset
button if no AX.25 packets are transmitted after a certain time. Details
on this hardware can be obtained from Tony Querubin. Send him some email
at tony@hits.net.
Is there a domain name server
for the .ampr.org domain?
Yes there is. The Internet machine ucsd.edu is the authorative domain name
server for the .ampr.org domain. Its information is available to all the
other domain name servers on the Internet. Therefore, you do not need to
include it in the list of domain name servers your gateway queries for
information. Just use your local domain name servers.
The gateways also provide an excellent point for non-Internetters to
get ampr.org information. If you can afford it, you should make your gateway
a name server cache, and then AMPRnet people can use you as a domain name
server. To do this under NOS, add the following commands:
domain addserver your.local.dns
domain addserver another.local.dns
domain cache wait 30000
domain cache size 200
domain cache clean off
domain maxwait 30
domain start
For example, fuller.net and n7vmr.ampr.org runs a domain name server.
How can I get updates into the
.ampr.org nameserver?
Brian Kantor (brian@ucsd.edu) runs a mail receiver which takes changes
to the .ampr.org nameserver information, and puts them into the ucsd.edu
authorative server. Currently, submissions to the nameserver must be submited
by the ampr IP coordinators.
How Does TCP Access and IP Access
Work?
A file called access.rc
on ftp.fuller.net in the hamradio/gateways directory explains how to do
this. It is long so I didn't include it here. You can source this file
from your autoexec.nos batch file, which keeps things modular.
Updated: James Fuller Fri Jun 25 09:53:30 MST 1999
Warren Toomey
Fri May 26 10:50:07 EST 1995
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