Gidday

The setup looks okay at first glance,

Is a -0 SSID valid for a hardware address?

Is gfk@ali a root user? I had lots of trouble running TCP/IP AX25 apps
as a non priv user on my old SuSE system. Something about denying port
access. Didnt actually try "call" in user mode though.

Strange how SLUG's ifconfig doesnt show the hardware address. There has
to be an ARP system somewhere. ie the TCP/IP system must know which
hardware to bind to, then a map of the remote devices IP vs hardware
layer address. One of the first things that happens in a TCP/IP
conversation is for the sender to shout out on the network "who has this
IP address". The unit that has the address says "me me me!" which
advises the sender the correlation between hardware and IP.

Perhaps ARP is timing out? Hmmm. Well you can certainly add a static
entry for each end of the link. This will also make first data exchange
a little faster;

arp -a - lists the known table

On ali
arp -s 172.25.25.2 VA2JF-0

On SLUG
arp -s 172.25.25.1 VA2JF-1

On slug you also might like to set the HW address manually;
ifconfig ax0 hw ax25 VA2JF-0

Then try the ping again..

Tell us how you go..

OBTW I remember too that tcpdump doesnt work on an ax25 interface. You
might try that to see if you get any valid data. This will show the arp
conversation as well as IP Ethereal is also a nice GUI of this.

Cheers Bob W5/VK2YQA East Texas


wrote:

Hi all,

I'm trying to setup a wireless link between two Linux using ConnexLink
900 MHz serial modems (http://www.aerocomm.com/Devices/link.htm). One
side (ali) is a regular PC running Debian Linux testing and the other
side (SLUG) is a NSLU2 running N7IPB's OpenSlug mod
(http://wetnet.net/).

The AX.25 link seem to work fine, I'm able to communicate between the
two sides with "call", but I can't figure out how to pass TCP/IP
through the link.

Anyone idea about what's going on?

Here's the relevant (I think) data from both hosts:
========================================
root@SLUG:~# cat /etc/ax25/axports
#Name Callsign baudrate paclen window Description
connex VA2JF-0 115200 1500 1 ConnexLink 900 MHz
root@SLUG:/etc/ax25# /usr/sbin/kissattach -l /dev/ttyUSB0 connex
172.25.25.2
AX.25 port connex bound to device ax0
root@SLUG:~# ifconfig ax0
ax0 Link encap:UNSPEC HWaddr
AC-82-64-94-8C-40-00-FF-00-00-00-00-00-00-00-00
inet addr:172.25.25.2 Bcast:172.25.255.255 Mask:255.255.0.0
UP BROADCAST RUNNING MTU:1500 Metric:1
RX packets:301 errors:0 dropped:0 overruns:0 frame:0
TX packets:61 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:10
RX bytes:17345 (16.9 KiB) TX bytes:2788 (2.7 KiB)
root@SLUG:~# /sbin/route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use
Iface
172.25.25.0 0.0.0.0 255.255.255.0 U 0 0 0
ax0
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0
eth0
172.25.0.0 0.0.0.0 255.255.0.0 U 0 0 0
ax0
0.0.0.0 192.168.0.3 0.0.0.0 UG 0 0 0
eth0
root@SLUG:~# mheard
Callsign Port Packets Last Heard
VA2JF-1 connex 463 Mon Dec 19 21:08:44
root@SLUG:~# axparms -route list
callsign dev mode digipeaters

root@SLUG:~# ping -c 10 172.25.25.1
PING 172.25.25.1 (172.25.25.1): 56 data bytes

--- 172.25.25.1 ping statistics ---
10 packets transmitted, 0 packets received, 100% packet loss
========================================
root@ali:~# cat /etc/ax25/axports
# name callsign speed paclen window description
connex VA2JF-1 115200 1500 1 ConnexLink 900 MHz
root@ali:# kissattach -l /dev/ttyS1 connex 172.25.25.1
AX.25 port connex bound to device ax0
gfk@ali:~$ /sbin/ifconfig ax0
ax0 Link encap:AMPR AX.25 HWaddr VA2JF-1
inet addr:172.25.25.1 Bcast:172.25.255.255 Mask:255.255.0.0
UP BROADCAST RUNNING MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:165 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:10
RX bytes:0 (0.0 b) TX bytes:8085 (7.8 KiB)

gfk@ali:~$ /sbin/route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use
Iface
172.25.25.0 0.0.0.0 255.255.255.0 U 0 0 0
ax0
10.10.16.0 0.0.0.0 255.255.255.0 U 0 0 0
eth0
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0
eth0
172.25.0.0 0.0.0.0 255.255.0.0 U 0 0 0
ax0
0.0.0.0 192.168.0.3 0.0.0.0 UG 0 0 0
eth0
gfk@ali:~$ mheard
Callsign Port Packets Last Heard
VA2JF connex 118 Sat Jan 28 16:44:54
gfk@ali:~$ sudo axparms -route list
callsign dev mode digipeaters

gfk@ali:~$ ping -c 10 172.25.25.2
PING 172.25.25.2 (172.25.25.2) 56(84) bytes of data.
From 172.25.25.1 icmp_seq=1 Destination Host Unreachable
From 172.25.25.1 icmp_seq=2 Destination Host Unreachable
From 172.25.25.1 icmp_seq=3 Destination Host Unreachable
From 172.25.25.1 icmp_seq=4 Destination Host Unreachable
From 172.25.25.1 icmp_seq=5 Destination Host Unreachable
From 172.25.25.1 icmp_seq=6 Destination Host Unreachable
From 172.25.25.1 icmp_seq=7 Destination Host Unreachable
From 172.25.25.1 icmp_seq=8 Destination Host Unreachable
From 172.25.25.1 icmp_seq=9 Destination Host Unreachable
From 172.25.25.1 icmp_seq=10 Destination Host Unreachable

--- 172.25.25.2 ping statistics ---
10 packets transmitted, 0 received, +10 errors, 100% packet loss, time
9020ms
, pipe 4
========================================

Thanks a lot and 73,
GFK's

PS: I was able to make the link work with PPP, but PPP requires a
full-duplex link. So I had to enable the full-duplex simulation of the
modem. This cut the available bandwidth in half. I'm trying to see if
AX.25 would perform better since it doesn't require full duplex.

--
Guillaume Filion, ing. jr
Logidac Tech., Beaumont, Québec, Canada - http://logidac.com/
PGP Key and mo http://guillaume.filion.org/