View Single Post
  #1   Report Post  
Old January 31st 06, 03:02 PM posted to rec.radio.amateur.digital.misc
 
Posts: n/a
Default Can't run TCP/IP through AX.25 using Linux

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/