mDNS Device Discovery

This example demonstrates how to find the module on the network using a network discovery protocol such as mDNS, LLMNR or Netbios (Gecko OS includes support for all of these protocols). Network discovery enables you to connect with the module using a known domain, rather than a dynamically allocated IP address.

Note : mDNS is not available with some Android apps. See Networking and Security, Network Discovery, Android .

This example demonstrates how to:

Set up the module to connect to your local network
Start the Gecko OS mDNS service
Connect to the module via its mDNS domain
Advertise an mDNS service

Setup

To run this example follow these steps:

Connect Your Module to the Local Network

To configure mDNS, use a Gecko OS terminal - see Getting Started . Once you have a terminal connected, issue the following Gecko OS command to configure the credentials for the local network:

network_up -s

Enable the mDNS Daemon

Enable mDNS and specify the domain advertised by the module using the following commands:

set mdns.enabled 1
set mdns.name mymodule

Save the mDNS configuration, then restart the network:

save
network_down
network_up

The module automatically starts the network discovery service after connecting to the network.

The response from Gecko OS is similar to the following:

[Associating to mynetwork]
> Obtaining IPv4 address via DHCP
IPv4 address: 10.5.6.59
Starting mDNS
mDNS domain: mymodule.local
[Associated]

Ping the Module using the mDNS Domain

From a command line on a Mac or Windows PC connected to the same local network, send an ICMP ping to the module.

C:\> ping mymodule.local
Pinging mymodule.local [10.5.6.59] with 32 bytes of data:
Reply from 10.5.6.59: bytes=32 time=308ms TTL=128
Reply from 10.5.6.59: bytes=32 time=8ms TTL=128
Reply from 10.5.6.59: bytes=32 time=4ms TTL=128
Reply from 10.5.6.59: bytes=32 time=96ms TTL=128

NOTE : Some ISPs hijack the .local domain which confuses Microsoft Windows, so it may be necessary to omit .local from the name on Windows platforms.

If there is no response (on a Windows PC), try sending the ping directly to the module name instead.

C:\> ping mymodule
Pinging mymodule [10.5.6.59] with 32 bytes of data:
Reply from 10.5.6.59: bytes=32 time=33ms TTL=128
Reply from 10.5.6.59: bytes=32 time=17ms TTL=128
Reply from 10.5.6.59: bytes=32 time=5ms TTL=128
Reply from 10.5.6.59: bytes=32 time=29ms TTL=128

Advertise an mDNS Service

This example assumes the network credentials are set up as described in Connect Your Module to the Local Network .

To advertise an mDNS service, you need to start a Gecko OS server. This example uses the HTTP server. To enable the HTTP server, issue the Gecko OS commands:

set http.server.enabled     1
set http.server.api_enabled 1

Advertise the service using the mdns.service variable:

> set md s http "Test Server" "record1=on.record2=off.another=21"

The server name and TXT record name=value pairs are arbitrary in this case. For specific applications, there may be a required naming convention and format for the TXT record information.

Restart the network to begin advertising:

network_down
network_up

The response is similar to the following:

[Associating to My_Network]
In progress
> Obtaining IPv4 address via DHCP
IPv4 address: 10.5.6.82
Starting mDNS
mDNS domain: mymodule.local
Adding mDNS service: Test Server._http._tcp.local
HTTP and REST API server listening on port: 80
[Associated]

Note the line Adding mDNS service: Test Server._http._tcp.local .

This means a device capable of browsing for mDNS services will be able to discover your "Test Server" service in the .local domain, among the _http._tcp. services, and read its name and TXT record for additional information.

If you have a Bonjour browser app you can view the module's advertised services.

To disable advertising of the service, set the server's name to -1 : set md s http -1 Now bring the network down and back up:

network_down
network_up

The response is similar to the following:

[2019-01-01 | 06:44:48: Associating to My_Network]
In progress
> Obtaining IPv4 address via DHCP
IPv4 address: 10.5.6.82
Starting mDNS
mDNS domain: nealemodule.local
HTTP and REST API server listening on port: 80
[2019-01-01 | 06:44:51: Associated]

Note that the Adding mDNS service line no longer appears.

If you have a Bonjour browser app you can see that the module service is no longer advertised.

Supporting Gecko OS Versions

Gecko OS 4

Change Log

Modified	Changes
2019-01-01	Created