I'm trying to develop software that interfaces with a proprietary hardware system that's been working just fine on Windows. However, I'm facing challenges while transitioning to a Linux-based environment (specifically Kubuntu 25.10). The hardware system has its own internal DHCP server that assigns unique VLAN IDs to connected nodes for internal organization, but all devices, including my controlling PC, share the same subnet (10.0.0.x) without a gateway. The VLAN IDs don't impact my setup since the hardware doesn't require tagged packets. On Windows, it seems that VLAN processing isn't automatic, which is why I never noticed this issue before.
I've done some configuration with netplan and discovered that the VLAN IDs are causing communication problems. It would be super cumbersome to configure 35 separate VLANs for each device, especially since they're all on the same subnet. I'm looking for a way to ignore the VLAN IDs altogether or some alternative approach to interact with the system without complications. Any suggestions or insights on how to achieve this would be greatly appreciated!
4 Answers
It sounds like your network setup is a bit tricky! DHCP operates at Layer 3 while VLANs are Layer 2, so having different VLANs on the same subnet can lead to some serious communication issues. If you want all your hosts to interact without VLAN tags, the first step would be to find out what's adding those tags in the first place. It's usually configured on switches or routers, not DHCP servers. If you can resolve the tagging issue, communication should become smoother.
Yeah, dealing with tagged VLANs can be complicated! If the VLAN IDs are changing and you're trying to treat them as one network, it really complicates things. Are you sure the switch is handling all VLAN traffic properly? If not, it may be worth looking into how your connections are set up, whether they’re point-to-point or if all traffic passes through a central switch.
Honestly, I get where you're coming from, but trying to ignore VLAN tags completely can be more trouble than it’s worth. The idea behind them is to separate networks logically over the same physical medium. However, if your hardware allows, you could set up a bridge that combines those VLANs into a single virtual network for your Linux system. Otherwise, consider changing to a different switch that can handle VLAN stripping if that's feasible for you!
You might want to simply avoid setting VLAN IDs in your configurations. Sometimes low-end switches automatically tag all traffic which can cause frustrating issues. Just as a side note, have you thought about trying Debian-based systems? They tend to have a more stable package support which might help with your networking setup.
I've seen this with some Windows drivers as well that strip 802.1Q tags incorrectly, which might be what's making the setup work fine for you. If Linux requires strict VLAN ID adherence, you might need to rethink your hardware configuration.