17. Configuring the Rose Uplink and Downlink commands

If you are familiar with the ROM based Rose implementation you will be familiar with the method by which AX.25 users make calls across a Rose network. If a users local Rose node has the callsign VK2KTJ-5 and the AX.25 user wants to connect to VK5XXX at remote Rose node 5050882960 then they would issue the command:

c vk5xxx v vk2ktj-5 5050 882960

At the remote node, VK5XXX would see an incoming connection with the local AX.25 users callsign and being digipeated via the remote Rose nodes callsign.

The Linux Rose implementation does not support this capability in the kernel, but there are two application programs called rsuplnk and rsdwnlnk which perform this function.

17.1 Configuring a Rose downlink

To configure your Linux machine to accept a Rose connection and establish an AX.25 connection to any destination callsign that is not being listened for on your machine you need to add an entry to your /etc/ax25/ax25d.conf file. Normally you would configure this entry to be the default behaviour for incoming Rose connections. For example you might have Rose listeners operating for destinations like NODE-0 or HEARD-0 that you wish to handle locally, but for all other destination calls you may want to pass them to the rsdwnlink command and assume they are AX.25 users.

A typical configuration would look like:

#
{* via rose}
NOCALL   * * * * * *  L
default  * * * * * *  - root  /usr/sbin/rsdwnlnk rsdwnlnk 4800 vk2ktj-5
#

With this configuration any user who established a Rose connection to your Linux nodes address with a destination call of something that you were not specifically listening for would be converted into an AX.25 connection on the AX.25 port named 4800 with a digipeater path of VK2KTJ-5.

17.2 Configuring a Rose uplink

To configure your Linux machine to accept AX.25 connections in the same way that a ROM Rose node would you must add an entry into your /etc/ax25/ax25d.conf file that looks similar to the following:

#
[VK2KTJ-5* via 4800]
NOCALL   * * * * * *  L
default  * * * * * *  - root  /usr/sbin/rsuplnk rsuplnk rose
#

Note the special syntax for the local callsign. The `*' character indicates that the application should be invoked if the callsign is heard in the digipeater path of a connection.

This configuration would allow an AX.25 user to establish Rose calls using the example connect sequence presented in the introduction. Anybody attempting to digipeat via VK2KTJ-5 on the AX.25 port named 4800 would be handled by the rsuplnk command.