NetRom Qualities

One of the things that appears to have puzzled Node ops for decades is understanding of NetRom Qualities. A PDF from NEDA(1) drafted in 1994 shows NetRom calculations based off of years of bench testing various settings for diode matrix based TheNet and X1J-4 nodes. While we’ve migrated off Diode Matrix configurations in favor of PC controlled ones we need to make adjustments due to the pounded/hidden backbone link nodes that aren’t in use via axip/axudp linkage.

First lets understand that in the NEDA found quality table anything over a quality of 203 for neighbor links is a statement that the linked node resides physically on your lan. As found by NEDA 228 is a good link for lan based nodes as it will propagate quality to the next hop as 203.

Here BAUNOD links to RSBYPI and it’s link quality is set to 203:

RSBYPI:N1URO-2} Connected to BAUNOD:ZL2BAU-3
BAUNOD:ZL2BAU-3} Routes:
Link Intface Callsign  Qual Nodes Lock  QSO
—- ——- ——— —- —– —-  —
>    ax0     N1URO-2    203    50         1

BBSURO is a neighbor node to RSBYPI 2 hops away thus it should appear with a derated quality of 181 on BAUNOD:

n bbsuro
Which Qual Obs Intface Neighbour
—– —- — ——- ———
>      181   6 ax0     N1URO-2
162   6 ax0     SV1CMG-4

Now let’s visit a node 3 hops away which should appear with a quality of


n mfnos
BAUNOD:ZL2BAU-3} Routes to: MFNOS:N1URO-14
Which Qual Obs Intface Neighbour
—– —- — ——- ———
>      198   6 ax0     SP2L-14
193   6 ax0     SV1CMG-4
161   6 ax0     N1URO-2

Yes it is there but as a tertiary route! This is how and why netrom brakes. It’s not the protocol, it’s the sysops. 198 and 193 are a higher quality and suggests something very wrong. It should appear with a
quality of 181 via SP2L-14 however even if that were true it’d be a secondary path which is false in nature. Let’s look at the other two


MFNOS:N1URO-14        usa    250 6/B    5 0     0         0 %

2LJNOS:SP2L-14 Area: n1uro

While neighbors, link quality of 250 suggests Poland is handing out N1 calls now since the claim is MFNOS physically is on a lan in Poland. The quality shown at BAUNOD should be shown at 181 since it’s 2 hops via SP2L, and SP2L should show 203. The fact that it’s the primary path is correct being 2 hops vs 3 but it’s quality is being falsely raised due to the link quality of 250 used by SP2L. Think about it this way, if the true host is sending OBS (nodes) broadcasts at a quality of 203, how could it logically be possible to be a higher quality elsewhere?

Let’s look at the secondary route:

LAMURO:SV1CMG-4} Routes:
Link Intface Callsign  Qual Nodes Lock  QSO
—- ——- ——— —- —– —-  —
>    axudp   GB7COW-5   255   168         0
jnos    SV1CMG-6   255   781         0
>    axip    ZL2BAU-3   255    83         1
>    radio1  SV1HCC-14  255   154         1
>    bpq     SV1CMG-7   255   500         0
axudp   NA7KR-5    255     3         0
>    xnet    SV1CMG-3   255   162         0
axip    SV1UY-12   255     6         0
>    axip    OK2PEN-5   255     3         0
axip    SV1DZI-11  255    62         0
>    tnos    SV1CMG-14  255   187         0
>    axudp   PI1LAP-5   255    34         0
>    fbb     SV1CMG-3    10     0         0

This I don’t at all understand. It appears Greece now is handing out calls from all over the globe since quality is 255! So now the question is, how does a node (MFNOS) which doesn’t link to LAMURO show a priority path to BAUNOD via LAMURO? This is known as hijacking routes. If SP2L was configured for 203, ZL2BAU would then receive MFNOS at a quality LOWER than the 193 received by SV1CMG-4 -= WHICH DOESN’T HAVE A LINK TO MFNOS!!=- so hopefully now you can see how NetRom paths get hijacked.

Since axip/axudp links don’t use backbone/#alias nodes for internlinking, they’re direct, we then adjust our minqual to reflect such so that we avoid:

– hijacking paths
– spew nodes that are not connectable due to excessive hops

To accomplish this via vanilla NetRom (NOT INP3      / Xnet) the following has been tested to be quite valid for nrbroadcast:

min_obs: 4
def_qual: 203
worst_qual 128
verbose 1

If you have a neighbor with X-net based links then set your verbose on all your interfaces to 0 and worst_qual to 202, or if you have a neighbor on the same link interface running link qualities NOT equal to the same mathematical calculations set your verbose to 0 AND raise your worst_qual to 202 to reject falsely raised qualities from infesting your nodes tables.

*Keep in mind this as well; a user on HF (aka: 300 baud) is most likely going to time out off of your node if you have more than a screen worth of CONNECTABLE nodes… and having a nodes table of truly connectable nodes will bring credibility to your system and those end users you may get to visit will appreciate the integrity of your network.

I’ve had some netrom based queries lately so I hope this answers questions others have had. When the protocol is treated properly by sysops it’s not a bad dynamic routing protocol but when the humans abuse it… then it becomes troublesome.


Brian n1uro

SystemD and Uronode

It`s also possible to run uronode with Systemd.. The systemd files can be found is the source directory of uronode. /uronode-2.8.1/systemd/

A sort list what to do.

The systemd files unit files


The uronode.socket


The uronode@.service


You can also start the ax25 system with Systemd.

Copy the ax25.system file /uronode2.8.1/systemd to the /lib/systemd/system directory


Systemd / Systemctl and Linbpq

Update : Okay, i relay dont like systemctl….
apt-get install sysvinit  / apt-get install openbsd-inetd / apt-get purge systemd / reboot

Debian Jessie uses the “new” systemd. No more inittab and inetd.conf. So a unit file must come up for this.

Now let`s check all startup nicely.

Up and running

Update Debian Wheezy to Jessie

Last night I updated the system to Debian Jessie. This did not go without a struggle. But we are online again.

Upgrade Debian Wheezy to Jessie safely

First make a complete backup of your system. I use rsync for this and put the backup on a remote vps.

Make sure that your system is completely updated.

Update the sources.list for Jessie

After this run a update again

Okay now reboot (thumbs crossed)

You will probably encounter some problems. I had some problems with apache2, but after some searching, he is also up and running again.


Follow up : Setup new System on PI1LAP

This is a follow up on this post

Today the SSD’s are installed in the PC. I ran into quite a few problems. Hardware-based raid is not possible with the PCI card and SSDs. Now the mainboard can also raid. Unfortunately, the SSDs are not recognized here. Cheap is expensive. So now over to software raid. Software raid runs perfectly. But here I have to hand in speed.

Here below the benchmark of the old sata hard disks. The old sata 80Gb disks were in Hardware-based raid. Cheap pci card from Delock. Both systems use raid 1.

I use the same command for both tests.

Here you see a read of 121 iops (Input/Output Operations per Second) and a write of 40 iops.

Now here is a benchmark with the ssd’s.

Here you can see that the iops are much more. So we make progress. It`s not much iops of 3800 for a ssd. But probably is the software raid the cause. And the old system perhaps.

md0 is the array and the sda and sdb are the ssd disk in the array.

I have read several tests about SSD hard disks. If I write 10Gb to the SSD per day, I can probably do 209 years with it. Let’s take 5% of that, is still more then 10 years. But yes you never know with a hard disk.

mdadm is running in the background to monitor the array. Is there something wrong I get a email.

This is a nice website about software raid.

Forward from linbpq through uronode to fbb.

There were some problems getting the forward from linbpq through a uronode to a linfbb bbs. I spent a while testing to see if we could get things going. It actually works pretty well.

I have add the following connection script to linbpq

ATT 3 stands for attach port 3, and port 3 is in my system the telnet port.

Furthermore, in uronode.conf I have created an Alias with the name BBS. So if the command BBS is given in uronode, you will be connected with linfbb.

We can test whether the forward script does what it is supposed to do. Let’s start the forward in Linbpq.

Log file of Linbpq

Okay looks good.

Install Dxspider on a Debian system

Here is a list of command’s that i use to install dxspider on a fresh system.

Install the perl modules

Simlink and reboot

After restart login as sysop

Next create the sysop

Next get the us database

The next step can take a few minutes

Let start the cluster

On a separate ssh or system console, log into the system as sysop

From the command line of the console enter:

Edit /etc/inittab to add the following two lines at the end of the file.
Start DXSpider on bootup and respawn it should it crash.

Add a line to /etc/services for spider

Add a line to /etc/inetd.conf for spider

Add a node to your system.
Create in the dir /spider/connect a file with the name of the node.

Chmod 4755 pi1lap-4

Now login to your spider.


Installing openvpn on Linux Debian wheezy 7

I have installed openvpn on my Debian system so it’s possible to surf with my winhoos laptop on the amprnet. Work quite nice

In this description I do not give much text and explanation. On the internet there is plenty to find about configuring openvpn.

This is what I use, it’s a simple setup.

Enable Packet Forwarding


Save and exit

Changes to your own needs.

In the same vars file, also edit this one line shown below.

Also changes to your own needs.


Cd to directory easy-rsa

Hit ENTER to accept defined, default values.

Please enter the following ‘extra’ attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:

Press ENTER to pass through each one.

Hit (Y) and enter

Sign the certificate? [y/n]
1 out of 1 certificate requests certified, commit? [y/n]

Generate Certificates and Keys for Clients

Press ENTER to accept the defaults.

Please enter the following ‘extra’ attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:

Hit (Y) enter

Sign the certificate? [y/n]
1 out of 1 certificate requests certified, commit? [y/n]

Copy the the files to the client computer in the c:\certs directory.


axMail admin util “spamblock”

There is a spamblock util for axMail. It’s handy to block spam.
Here can you get the program.

Read the INSTALL file carefully. If you do not have the line smtpd_client_restrictions in your you need to add it.

The complete rule is ….

Let test the program.

Now let test if you can send mail by postfix.

Okay that just work quit well. Have a look in the file /etc/postfix/access

Delete the last line if you want to send e-mail. And “postfix reload”


Uronode update version 2.8.1

Brian n1uro just released a minor update. To correct some issues.


Bugs i love bugs.