[Feature Request]: Make local MQTT meshtastic server discoverable in defined ways.

[oiaohm]

Mosquitto does not built in discovery there are different options.

Option 1) "bootp dhcp"
https://www.iana.org/assignments/bootp-dhcp-parameters/bootp-dhcp-parameters.xhtml
224-254 Reserved (Private Use) could be used right away with dhcp to broadcast where the local meshtastic MQTT is. Of course application to iana for a assigned number for meshstatic usage with dhcp/bootp would be the recommend long term route.

Option 2) mdns/avahi/zeroconf
arendst/Tasmota#11403
Yes this does note some problems.

<!-- Put this in /etc/avahi/services/mosquitto.service -->
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
<service-group>
 <name replace-wildcards="yes">Mosquitto MQTT server on %h</name>
  <service>
   <type>_mqtt._tcp</type>
   <port>1883</port>
   <txt-record>info=Publish, Publish! Read all about it! mqtt.org</txt-record>
  </service>
</service-group>

Yes you can make up a generic make mosquitto MQTT visible on mdns. But I have no where in the meshtastic documentation how this should look on mdns if this MQTT server for meshtastic clients to use.

As the Tasmota issue notes some firmware have trouble doing mdns/avahi. But still project does not have a define way it should advertise meshtastic local servers by mdns/avahi/zeroconf

Option 3) Custom local DNS record/records.
this is a lot like the mdns record.

Lot of people are not aware we could create domain name meshtastic.local with TXT records only containing client configuration information just like option2/mdns txt-record line you are allowed more line of this.

Yes both option 2 and option 3 we do not have what before the = for the txt-record/TXT to use these effectively.

txt-record or TXT have the same format. "what this is"="the data"
Yes protocol could define like that
meshtastic-domainname= in TXT is the domainname of the meshtastic MQTT server.
meshtastic-ipv4=is the ipv4 of the meshtastic MQTT
meshtastic-port= the port the server is on.
There could be been radio configuration.

Yes there is no documentation on how to setup meshtatic MQTT on DNS so that you can find by DNS.

Part of making this meshtastic MQTT discoverable can be making meshtatic configuration for a event discoverable by connecting to a local wifi access point to reduce issues caused by devices not all being on the same page. This could make bootstrapping/configuring many new meshtatic devices simple as connect authorized local wifi network that provides the configuration.

[caveman99]

Please don't open issues in random repositories about this, discussion is here. meshtastic/firmware#5649