Differences

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--- packet:kernel-ax25-pi [2023/04/15 21:45] – m0lte
+++ packet:kernel-ax25-pi [2023/04/16 23:40] (current) – Updating m0gzp
@@ Line 1: / Line 1: @@
 ===== Raspberry Pi and Linux Kernel AX.25 support =====
-This page documents how to set up a Raspberry Pi running Raspberry Pi OS Lite (32 bit).
+This page documents how to set up a Raspberry Pi running Raspberry Pi OS Lite (32 bit), and was written by Szymon M0GZP.
 It is possible to do this on 64 bit Raspberry Pi OS as well, so long as you are consistently using 32 bit or 64 bit throughout; see the notes below.
@@ Line 13: / Line 13: @@
 ==== Equipment ====
-My setup consists of:
+This example setup consists of:
   * Raspberry Pi 4b
   * CG Antenna 2000 Radio Interface
@@ Line 19: / Line 19: @@
   * Tait 2010 VHF Radio
   * ICOM IC7300 HF Radio
+but the same principles apply with different radios, audio and radio interfaces.
 ==== Software Prereqs ====
 ''sudo apt install libax25 ax25-apps ax25-tools socat direwolf''
+You do not need to install socat or direwolf packages if you will be using a hardware TNC such as NinoTNC.
 Notes:
   * make absolutely certain that you are using a 32bit kernel if you have 32bit user binaries.  I somehow ended up with a 64bit kernel and things broke in very subtle ways.  Check that ''uname -m'' returns ''armv7l'' if you installed a 32bit OS!
-  * you may need to use ''rpi-update'' to get the latest series 6 kernel
+  * you currently need to use ''rpi-update'' to get the latest series 6 kernel - there are unfixed AX.25 bugs in the version 5 kernel available at the time of writing.
 ==== TNC ====
-I use Direwolf to run the two radios.  Here is my Direwolf config:
+The author uses Dire Wolf to run the two radios. Dire Wolf is a fundamentally a KISS modem implemented in software and using a sound card. An alternative to using a sound card based KISS modem is to use a hardware device such as NinoTNC. The same overall steps still apply, just using a piece of hardware as the modem instead of a piece of software.
+Here is a suitable Dire Wolf config:
 <code>
@@ Line 66: / Line 72: @@
 This file sets up two AX.25 ports, one for VHF and one for HF
 <code>
-v144    M0GZP-1         19200   236     4       144.375 Mhz 1k2bps
+VHF     M0GZP-1         19200   255     4       144.375 Mhz 1k2bps
-HF      M0GZP-2         19200   236     4       HF 300bps
+HF      M0GZP-2         19200   200     4       HF 300bps
 </code>
@@ Line 73: / Line 79: @@
 This file sets up a NET/ROM port aliased as GZPNOD
 <code>
-netrom  M0GZP-7 GZPNOD  236     Linux Switch Port
+nrvhf   M0GZP-5 GZPVHF  235     VHF NET/ROM Port
+nrhf    M0GZP-6 GZPHF   40      HF NET/ROM Port
 </code>
+NOTE: nrports cannot contain any blank lines.
 === nrbroadcast ===
-This file configures how our AX.25 ports will broadcast NET/ROM nodes.  My VHF node sets all seen nodes to a default quality of 220, and will broadcast any node with a minimum quality of 200.  The HF node on the other hand sets all nodes to a default quality of 199 (so as not to advertise HF nodes over VHF), and will broadcast nodes with a minimum quality of 199.
+This file configures how our AX.25 ports will broadcast NET/ROM nodes.  My VHF node sets all seen nodes to a default quality of 220, and will broadcast any node with a minimum quality of 200.  The HF node on the other hand sets all nodes to a default quality of 200 (so as not to advertise HF nodes over VHF), and will broadcast nodes with a minimum quality of 200.
 <code>
-v144    5       220     200     1
+VHF     5       200     200     1
-HF      5       199     199     1
+HF      5       220     200     1
+</code>
+=== ax25d.conf ===
+This file configures the ax25 userspace daemon, which determines what processes are run when other users connect in to the node.  In my example, I am calling the program uronode (by N1URO, sadly SK).  A separate entry is required for each port.
+<code>
+[M0GZP-1 via VHF]
+NOCALL   * * * * * *  L
+default  * * * * * *  0 root  /usr/local/sbin/uronode   uronode
+[M0GZP-2 via HF]
+NOCALL   * * * * * *  L
+default  * * * * * *  0 root  /usr/local/sbin/uronode   uronode
+<nrhf>
+NOCALL   * * * * * *  L
+default  * * * * * *  0 root  /usr/local/sbin/uronode   uronode
+<nrvhf>
+NOCALL   * * * * * *  L
+default  * * * * * *  0 root  /usr/local/sbin/uronode   uronode
 </code>
@@ Line 93: / Line 122: @@
   * Load the ''netrom'' module and attach it to the port defined in nrports
   * Run the netrom userspace daemon which handles the netrom broadcasts
+  * Load previous netrom node tables
+  * Run the mheard daemon which keeps track of heard stations
+  * Run the ax25 daemon to support running services
 <code>
 #!/bin/bash
@@ Line 101: / Line 133: @@
 echo Done
 echo -n Attaching KISS interfaces for direwolf...
-kissattach `ls -l /tmp/kiss8001 | awk '{ print $11 }'` v144
+kissattach -l `ls -l /tmp/kiss8001 | awk '{ print $11 }'` VHF
 sleep 1
-kissattach `ls -l /tmp/kiss8002 | awk '{ print $11 }'` HF
+kissattach -l `ls -l /tmp/kiss8002 | awk '{ print $11 }'` HF
+sleep 1
+echo Done
+echo -n 'Bringing up NET/ROM runtime...'
+modprobe netrom
+nrattach nrvhf
+nrattach nrhf
+netromd -i -l -d
+echo -n Restoring node tables...
+[ -x /etc/ax25/nodesave.sh ] && /etc/ax25/nodesave.sh
+echo Done
+echo -n Starting mheard daemon...
+mheardd -l
+echo Done
+echo -n Starting ax25 daemon...
+ax25d -l
+echo Done
+</code>
+For a modem other than Dire Wolf, an alternative script can be used:
+<code>
+#!/bin/bash
+echo -n Attaching KISS interfaces...
+kissattach /dev/ttyACM0 HF
 sleep 1
 echo Done
@@ Line 114: / Line 170: @@
 echo Done
 </code>
+NB this script appears to run before /dev/ttyACM0 is available, so currently doesn't work. I'm coming up with a fix.
 === /usr/sbin/stopRadio.sh ===
 This script does the opposite to startRadio, killing the processes and taking down the interfaces
+<code>
+#!/bin/bash
+echo -n Saving node tables...
+/usr/sbin/nodesave > /etc/ax25/nodesave.sh && chmod 755 /etc/ax25/nodesave.sh
+echo Done
+echo -n Killing mheard daemon...
+killall mheardd
+sleep 1
+echo Done
+echo -n Killing ax25 daemon...
+killall ax25d
+sleep 1
+echo Done
+echo -n Killing all socat processes in case they do not end cleanly...
+killall socat
+sleep 1
+echo Done
+echo -n Killing all kissattach processes...
+killall kissattach
+sleep 1
+echo Done
+echo -n Killing the netromd process...
+killall netromd
+sleep 1
+echo Done
+echo -n Taking down the netrom interface...
+ifconfig nr0 down
+sleep 1
+echo Done
+echo -n Removing kernel modules...
+rmmod netrom && sleep 1 && rmmod mkiss && sleep 1 && rmmod ax25 && sleep 1
+echo Done
+echo -n Taking down the AX.25 interfaces...
+ifconfig ax0 > /dev/null 2>&1 && ifconfig ax0 down
+ifconfig ax1 > /dev/null 2>&1 && ifconfig ax1 down
+sleep 1
+echo Done
+</code>
+For a modem other than Dire Wolf, an alternative script can be used:
 <code>
 #!/bin/bash
@@ Line 123: / Line 222: @@
 echo Killing all kissattach processes
 killall kissattach
-echo Killing all socat processes in case they do not end cleanly
-killall socat
 echo Killing the netromd process
 killall netromd
@@ Line 135: / Line 232: @@
 echo Taking down the AX.25 interfaces
 ifconfig ax0 > /dev/null 2>&1 && ifconfig ax0 down
-ifconfig ax1 > /dev/null 2>&1 && ifconfig ax1 down
 echo Done
+</code>
+Don't forget to make these scripts executable:
+<code>
+chmod +x /usr/sbin/startRadio.sh
+chmod +x /usr/sbin/stopRadio.sh
 </code>
@@ Line 144: / Line 247: @@
 [Unit]
 Description=Start up radio processes
+After=direwolf.service
+Requires=direwolf.service
 [Service]
@@ Line 162: / Line 267: @@
 ● ax25.service - Start up radio processes
      Loaded: loaded (/lib/systemd/system/ax25.service; disabled; vendor preset: enabled)
-     Active: active (exited) since Wed 2023-04-12 22:16:27 BST; 4s ago
+     Active: active (exited) since Mon 2023-04-17 00:36:38 BST; 7s ago
-    Process: 2476 ExecStart=/usr/sbin/startRadio.sh (code=exited, status=0/SUCCESS)
+    Process: 3036 ExecStart=/usr/sbin/startRadio.sh (code=exited, status=0/SUCCESS)
-   Main PID: 2476 (code=exited, status=0/SUCCESS)
+   Main PID: 3036 (code=exited, status=0/SUCCESS)
-      Tasks: 5 (limit: 4915)
+      Tasks: 7 (limit: 4915)
-        CPU: 151ms
+        CPU: 156ms
      CGroup: /system.slice/ax25.service
-             ├─2477 socat pty,echo=0,link=/tmp/kiss8001,wait-slave tcp:127.0.0.1:8001
+             ├─3037 socat pty,echo=0,link=/tmp/kiss8001,wait-slave tcp:127.0.0.1:8001
-             ├─2478 socat pty,echo=0,link=/tmp/kiss8002,wait-slave tcp:127.0.0.1:8002
+             ├─3038 socat pty,echo=0,link=/tmp/kiss8002,wait-slave tcp:127.0.0.1:8002
-             ├─2486 kissattach /dev/pts/4 v144
+             ├─3047 kissattach -l /dev/pts/4 VHF
-             ├─2501 kissattach /dev/pts/2 HF
+             ├─3061 kissattach -l /dev/pts/3 HF
-             └─2519 netromd -i -l -d
+             ├─3089 netromd -i -l -d
+             ├─3099 mheardd -l
+             └─3104 ax25d -l
-Apr 12 22:16:25 radio startRadio.sh[2483]: AX.25 port v144 bound to device ax0
+Apr 17 00:36:38 radio startRadio.sh[3077]: NET/ROM port nrvhf bound to device nr0
-Apr 12 22:16:25 radio startRadio.sh[2486]: AX.25 port v144 bound to device ax0
+Apr 17 00:36:38 radio startRadio.sh[3082]: NET/ROM port nrhf bound to device nr1
-Apr 12 22:16:26 radio startRadio.sh[2499]: AX.25 port HF bound to device ax1
+Apr 17 00:36:38 radio netromd[3089]: starting
-Apr 12 22:16:26 radio startRadio.sh[2501]: AX.25 port HF bound to device ax1
+Apr 17 00:36:38 radio startRadio.sh[3036]: Restoring node tables...Done
-Apr 12 22:16:27 radio startRadio.sh[2476]: Done
+Apr 17 00:36:38 radio mheardd[3099]: starting
-Apr 12 22:16:27 radio startRadio.sh[2476]: Bringing up NET/ROM runtime...
+Apr 17 00:36:38 radio startRadio.sh[3036]: Starting mheard daemon...Done
-Apr 12 22:16:27 radio startRadio.sh[2512]: NET/ROM port netrom bound to device nr0
+Apr 17 00:36:38 radio startRadio.sh[3036]: Starting ax25 daemon...Done
-Apr 12 22:16:27 radio netromd[2519]: starting
+Apr 17 00:36:38 radio systemd[1]: Finished Start up radio processes.
-Apr 12 22:16:27 radio startRadio.sh[2476]: Restoring node tables...Done
+Apr 17 00:36:38 radio ax25d[3104]: starting
-Apr 12 22:16:27 radio systemd[1]: Finished Start up radio processes.
+Apr 17 00:36:38 radio ax25d[3104]: new config file loaded successfully
 szymon@radio:~ $
 </code>
@@ Line 189: / Line 296: @@
 You will see some new network interfaces on ifconfig (I've removed my normal interfaces):
 <code>
-ax0: flags=67<UP,BROADCAST,RUNNING>  mtu 236
+ax0: flags=67<UP,BROADCAST,RUNNING>  mtu 255
         ax25 M0GZP-1  txqueuelen 10  (AMPR AX.25)
         RX packets 0  bytes 0 (0.0 B)
         RX errors 0  dropped 0  overruns 0  frame 0
-        TX packets 2  bytes 77 (77.0 B)
+        TX packets 1  bytes 49 (49.0 B)
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
-ax1: flags=67<UP,BROADCAST,RUNNING>  mtu 236
+ax1: flags=67<UP,BROADCAST,RUNNING>  mtu 200
         ax25 M0GZP-2  txqueuelen 10  (AMPR AX.25)
         RX packets 0  bytes 0 (0.0 B)
         RX errors 0  dropped 0  overruns 0  frame 0
-        TX packets 2  bytes 77 (77.0 B)
+        TX packets 0  bytes 0 (0.0 B)
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
-nr0: flags=193<UP,RUNNING,NOARP>  mtu 236
+nr0: flags=193<UP,RUNNING,NOARP>  mtu 235
-        netrom M0GZP-7  txqueuelen 1000  (AMPR NET/ROM)
+        netrom M0GZP-5  txqueuelen 1000  (AMPR NET/ROM)
+        RX packets 0  bytes 0 (0.0 B)
+        RX errors 0  dropped 0  overruns 0  frame 0
+        TX packets 0  bytes 0 (0.0 B)
+        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
+nr1: flags=193<UP,RUNNING,NOARP>  mtu 40
+        netrom M0GZP-6  txqueuelen 1000  (AMPR NET/ROM)
         RX packets 0  bytes 0 (0.0 B)
         RX errors 0  dropped 0  overruns 0  frame 0
@@ Line 212: / Line 326: @@
 You can now use ''axcall'' to contact another node, ''axlisten'' to monitor traffic, etc.
+If it was all successful, enable the service to start at boot:
+<code>
+sudo systemctl enable ax25.service
+</code>