I've been struggling for weeks to figure out a networking issue on my Kubuntu 25.10 setup. I have a secondary local network connected to my machine, which communicates via UDP (addressing is in the 10.0.0.x range). Everything works smoothly on the Windows side, but I'm having significant trouble moving it to Linux. Currently, I can only ping and communicate with the gateway node (10.0.0.1), while I can see all broadcast traffic from the other nodes using tcpdump, but it never reaches my application. I've checked many settings:
1. No logs indicate dropped packets, but my logging may not be sufficient.
2. I've added exceptions in the firewall, and turning it off changes nothing.
3. The socket is correctly bound, as proven by ss output.
4. I have only one default route.
5. The routing table includes both my machine's address (10.0.0.200) and the appropriate subnet route.
6. I've tried various netplan configurations, but without success.
Any assistance would be greatly appreciated!
1 Answer
Hey! I see some possible gaps in your configuration. First off, could you clarify what you mean by '10.0.0.x over UDP'? Also, have you run 'ip a s' to check the IP settings? Make sure your service is indeed listening on the correct UDP port by using 'ss -l -u'. That might give us more hints about what's happening!
I meant all communications on this network use UDP exclusively. The address output shows that the adapter is correctly configured with 10.0.0.200. The service listens fine on the 10.0.0.1 node, but I'm unsure about messages from other nodes actually being received.