Troubleshooting tip for DMX/Ethernet converters (DMX-AN2, DIN Ethergate, ODE MK2/3, etc.)

Troubleshooting
1

I’ve been fighting a weird issue with DMX/Ethernet converters simply ceasing operation after a random but short period of time. At initial boot-up, the converter is working perfectly, Photon is able to control the lights, but at some point the converter just…stops. DMX signals cease, Photon has no control. I thought it was a bad converter, so I replaced a Chauvet DMX-AN2 with an old ENTTEC DIN Ethergate, but it did the same thing.

Very long story short, the problem was something on the network itself. The VLAN to which the converters were connected is used for all our FOH/BOH AV gear, some HomeKit stuff, etc. and something – still not sure what, exactly – is generating some kind of network traffic that causes the DMX converters to go silent. Once I moved the converters to a different VLAN, the problems ceased. The Photon iPads are still on the original VLAN, so are talking to the converters across the router, but it works perfectly.

When I have time, I’ll do more troubleshooting to see if I can work out what piece of equipment is causing the issue, but there’s a good chance that it’s a smart home appliance, many of which have poor-quality network implementations.

2

Thank you for sharing that !

HomeKit and other smart-home gear are especially noisy: constant mDNS announcements, service discovery floods, and sometimes poorly implemented multicast handling. Even if bandwidth usage is low, packet rate alone can be enough to cause DMX nodes to lock up or silently stop outputting DMX.

Moving the converters to a dedicated VLAN could be the correct fix and effectively confirms the root cause.

Thanks !

3

FWIW, the VLAN I’m using for the DMX-AN2 is configured to optimize NDI multicast streaming. That VLAN has IGMP Snooping enabled, with no mDNS or other multicast being routed to it from other subnets. This restricts multicast traffic to just the ports that need it, so the DMX-AN2 has a “quiet” network.