Yes, Signal K can receive broadcast UDP messages.
Yes, you need to restart the server to make connection settings take effect.
Often people have inadvertently configured something else, often OpenCPN, to listen on the same UDP port. Make sure there is nothing there. Use lsof to check:
lsof -i -P | grep 7777
where 7777 is your port number.
With nothing active on the port you can use nc to check that the UDP traffic is actually reaching your server:
nc -l -u 7777
or
nc -l -u -b wlan0 7777
where wlan0 is the network interface the traffic is supposed to be on. If there is incoming UDP traffic this will print it out.
With SK server running with an active UDP connection configured you can enable debug key
in server log you can see the incoming UDP traffic in the log. This helps to verify that the traffic is reaching the SK server.
You can verify that the server is receiving UDP properly by sending NMEA0183 data manually with nc:
echo '$GPRMC,210230,A,3855.4487,N,09446.0071,W,0.0,076.2,130495,003.8,E*69' | nc -u 127.0.0.1 7777
and you should see the data in the Server Log (with the debug key active).
(Testing the broadcast address with a single host does not work afaik - at least on a mac listening on a port and sending to the broadcast address does not result in any output.)
Yes, you need to restart the server to make connection settings take effect.
Often people have inadvertently configured something else, often OpenCPN, to listen on the same UDP port. Make sure there is nothing there. Use lsof to check:
lsof -i -P | grep 7777
where 7777 is your port number.
With nothing active on the port you can use nc to check that the UDP traffic is actually reaching your server:
nc -l -u 7777
or
nc -l -u -b wlan0 7777
where wlan0 is the network interface the traffic is supposed to be on. If there is incoming UDP traffic this will print it out.
With SK server running with an active UDP connection configured you can enable debug key
Code:
signalk:streams:udp
You can verify that the server is receiving UDP properly by sending NMEA0183 data manually with nc:
echo '$GPRMC,210230,A,3855.4487,N,09446.0071,W,0.0,076.2,130495,003.8,E*69' | nc -u 127.0.0.1 7777
and you should see the data in the Server Log (with the debug key active).
(Testing the broadcast address with a single host does not work afaik - at least on a mac listening on a port and sending to the broadcast address does not result in any output.)