ethernetNetwork
I have Mac1 connected via ethernet to a router.
The Mac1 has the IP 10.0.1.5
On this IP I have a Python-server listening to incoming UDP packets.
Now there is another Mac2 connected to Mac1 via a Thunderbolt-Ethernet Adapter. The IP of Mac1 on this adapter is 192.168.20.1
Mac2 sends UPD packets to this address.
How can i route this traffic internally on Mac1 from 192.168.20.1 to 10.0.1.5?
Both machines are on MacOS 10.10
Thanks a lot!
This depends a lot on your DHCP server, but I would look into using the client id to assign static IPs. It's not tied to the individual hardware (although you'd have to set it at least once when they first use a TB Display), so it avoids the switching displays problem. It can be set via the networksetup tool.
When an interface self-assigns an IP it generally means the interface isn't getting any response from your router or DHCP server. This is a feature of OS X to let the machines build an adhoc network when they cannot determine the actual network they're on -- you can put a bunch of Macs on a dumb hub and almost get them to self-organize and function with this feature.
Your router and DHCP server are going to see the MAC address listed for the device in the Network Preferences pane. Go to System Preferences -> Network and click on your Thunderbolt interface. Click on the Advanced... button and then on the Hardware tab:
That's the MAC address that your interface is broadcasting on the network when it's trying to acquire an IP on your network from your DHCP server.
Best Answer
There is no need to route anything. Just let the python-server also listen to incoming UDP packets at eth2 (192.168.20.1) assuming eth2 is the TB-Ethernet interface.