Sat Dec 02, 2023 5:31 am
I have had no end of trouble with BM devices (ATEMs, Hubs, etc.) on defined VLANs. Very odd issues, where ATEM receives DHCP response as requested only fail to honor it and default to a self-assigned IP address. The VERY second, I remove the VLAN specification on the switch port, so that the switch port is ONLY presenting the physical network, no VLAN tagging at all, the BM devices start working, connecting as expected.
Get this... with VLAN tagging enabled, i.e. native VLAN assignment on connected switch port, on Ubiquiti network components, if I do static assignment, on the BM devices, they will connect, I can ping them, see them in the network monitoring views, but do they work right? No the ATEM will refuse to route to the assigned (VLAN) gateway, thus never cross over to the internet, never streaming say to youtube. I can remove the cable plug it into any other device, PC, for example, everything works, DHCP and internet access. I then return the cable to the ATEM, reboot the ATEM... and BOOM... back to self-assigned IP address. I remove the VLAN tagging/VLAN configuration on switch port, reboot the ATEM, and all is working. So the bottomline is, something in how BM implements they DHCP handling is a bit off, and VLAN tagging seems to trigger it.
If any other device did not work as expected, I would not point to BM as having issues, but it is only the BM devices that seem to get 'confused' by the VLANs. Sorry if any disagree, but that has been my experience thus far, and it is consistent and repeatable. Frankly, I think so few customers have (more advanced network designs than) a simple LAN configuration, that this issue is flying under the RADAR a bit.